Browse Topic: Environmental testing

Items (1,436)

Exhaust Emissions Tests of Small Gasoline Engines Used as Drives for Power Generators and Handheld Machinery in Real-Operating Conditions

2026-01-5080

10/1/2026

The paper presents the results of investigations on the exhaust emissions carried out under real-world operating conditions of gasoline engines used in lawnmowers and power generators. During the operation of these engines, the authors measured the emissions of the following exhaust gaseous components: CO, HC, NOx, and CO2. For the measurements, the authors used Axion R/S+, a PEMS (Portable Exhaust Emission System) analyzer. The presented method is a new approach to exhaust emissions measurements performed on small engines. The emission coefficient, as a related value of the emission of harmful compounds and CO2, was proposed. Additionally, some remarks related to the measurement method were made. The paper presents the modal analysis of the investigations of the exhaust emissions from engines and the total mass of gaseous compounds. Moreover, the obtained results of the exhaust emissions from the power generator engine were compared with the applicable emission standards, and the real emissions of CO and HC+NOx were, respectively, about 10% and 38% higher than Stage II standards. Based on the investigation results, the authors considered the possibilities of using the said measurement method in real-world operating conditions, applying the PEMS equipment for small gasoline engines.

Lijewski, Piotr, Markiewicz, Filip, Fuć, Paweł, Dobrzyński, Michał, Wiśniewski, Sławomir

Emissions Reduction Assessment in Buses During Real Driving Tests using Hydrogen-Methane Blends as Fuel

2026-24-0006

9/21/2026

Increasing concern over climate change on planetary scale and urban pollution on a local spatial dimension are the pressing needs which invite to reduce greenhouse gas emissions in transportation as well as pollutant emissions. Both goals have prompted governments, industry stakeholders, and researchers to pursue innovative pathways toward sustainability in the on-the-road transportation sector trying to interpret this concept on the three requested dimensions, social, economic and environmental. Within this framework, hydrogen–methane mixtures have emerged as a promising alternative fuel solution which in someways match the three expectations. This primary solution matches the needs of urban transportation by buses, representing a further innovation step after the diesel-fuel to methane conversion. Hydrogen is characterized by carbon-free combustion, while methane is a comparatively clean and widely available fossil fuel. When blended, these two fuels can lower overall emissions relative to the use of pure CNG, while still being compatible with existing internal combustion engines if the content of hydrogen in the blend do not exceed 20 % by volume. Greater shares till to 35-40 % are compatible simply re-setting the ignition time according to the engine load. This compatibility makes the adoption of such blends both economically viable and technically achievable in the short to medium term, also increasing the market demand for hydrogen, reducing its cost. The social dimension of this choice is also saved, re-focusing attention on the reciprocating internal combustion engines which represent a great part of the industrial economy. This study describes the methodology adopted to assess the emissions performance of a hydrogen-methane-fueled (HCNG) bus for on-road emission testing. Two experimental campaigns were carried out: the first using conventional CNG, and the second employing an HCNG blend composed of 15% hydrogen and 85% CNG by volume. Tests were conducted along two routes, representing urban and extra-urban driving conditions, with different drivers and traffic conditions. The experimental results enabled a direct comparison between the two fuels. In both driving scenarios, a slight decrease in CO₂ emissions was observed when using the HCNG blend, corresponding to a reduction in fuel consumption. More significant decreases were recorded for pollutants such as CO, HC, and PN, whereas NOx emissions showed a modest increase of only a few percentage points. No modification has been implemented on the aftertreatment devices. The study indicates that the HCNG blend enhances vehicle responsiveness compared to conventional CNG and represents a step ahead in public urban transportation like the one from diesel fuel to methane.

Di Battista, Davide, Di Bartolomeo, Marco, Di Prospero, Federico, Di Diomede, Domenico, Cipollone, Roberto

Study on the “Vibration-Differential Pressure” Coupled Environment Test Technology for Airborne Equipment Vibration Isolation Systems

2026-99-1251

9/4/2026

The stable operation of airborne equipment determines the functionality and performance standards of aircraft. Installing vibration isolation systems on such equipment aims to improve its performance. With the advancement of aircraft capabilities, future evaluations of airborne equipment’s vibration isolation systems will require increasingly real-world experimental assessment. Achieving a ground-based simulation of the complex coupling environment encountered by airborne equipment at high altitudes presents a huge challenge. This paper proposes a method utilizing air springs to simulate differential pressure forces, successfully enabling ground-based testing of “vibration-differential pressure” coupled environments for airborne equipment. The results verify the effectiveness of this approach, and it can be used for this type of environmental testing.

Qin, Xiaomeng, Xing, Xiaoming, Mou, Haowen, Wang, Jianzhong

Research on Reliability and Durability Testing and Evaluation Technology for Hub Motor Corner Modules

2026-99-1236

9/4/2026

With the development of high-performance hub motors and modular assembly integration technologies, their reliability and durability have become key factors restricting industrial applications. Existing standards are mostly aimed at the hub motor itself, lacking systematic testing methods for highly integrated corner module systems. Based on a National Key Research and Development Program project, this paper conducts a series of research on reliability and durability test and evaluation technologies for the hub motor corner module system. By means of collecting vehicle-load spectra and combining user- relevance techniques, a multidimensional assessment framework is established, encompassing bench-scale axle-coupled tests, full- vehicle road reliability tests, and component-level environmental tests. The research outcomes have been applied to the testing and validation of actual prototype vehicles and components. Test results indicate that the developed testing methodology can effectively identify potential failure, providing crucial technical support for the optimized design and industrialization of hub motor corner modules.

Wu, Zhen, Liang, Dong, Gao, Fengling, Wang, Runze, He, Junnan

Development and Technical Verification of A Lunar Dust Environment Simulation Mechanism

2026-99-0175

7/31/2026

Lunar dust consists of extremely fine particles and exhibits electrostatic charging properties and electrostatic adhesion. These characteristics cause lunar dust to be highly susceptible to mobilization during lander touchdowns, rover traversals, and human activities, forming widely distributed dust clouds. Lunar dust contamination not only abrades spacecraft and equipment to impair their performance but also poses a threat to astronauts’ safety. To verify the impact of the lunar dust environment on exploration equipment components, a simulation mechanism adaptable to the thermal vacuum test environment was designed. This mechanism is integrated into the lunar environment simulation system and uses a vacuum stepper motor to drive a ratchet mechanism, enabling precise vibrational injection of simulated lunar dust. It mainly consists of a pretreatment mechanism, a particle sedimentation mechanism, a shielding mechanism, and an ultraviolet (UV) irradiation system. Considering the vacuum operating environment, alternating high and low temperature conditions, as well as the strict requirements for the mechanism’s compact size and high reliability, this paper analyzes in detail a series of problems encountered during the development of the mechanism and their corresponding solutions. Stainless steel and polytetrafluoroethylene (PTFE) were selected as the main materials for the mechanism. Meanwhile, active temperature control measures were adopted to actively regulate the temperature of components such as the motor. Ultimately, the mechanism can withstand alternating high and low temperatures ranging from -150°C to 150°C and a vacuum environment of 5 × 10^–6 Pa. Under this environment, the mechanism can achieve vibration frequency adjustment within the range of 1-5 Hz, and realize the sedimentation of simulated lunar dust particles with a particle size of less than 200 μm over an area of 150 mm × 150 mm. After sedimentation, the simulated lunar dust particles can be charged through the photoelectric effect.

Xu, Menglong, Lv, Shizeng, Li, Guohua, Gong, Jie

Research on Quadrotor Trajectory Tracking Based on Model Predictive Control

2026-99-1850

7/17/2026

Quadrotors (UAVs) are widely used in intelligent inspection, environmental monitoring, and logistics due to their simple structure, strong maneuverability, and vertical take-off and landing capabilities. However, their highly nonlinear, strongly coupled, and highly constrained dynamic characteristics make trajectory tracking control a challenging task. To improve trajectory tracking accuracy and control robustness, this paper proposes a quadrotor trajectory tracking method based on model predictive control (MPC). First, a six-degree-of-freedom dynamic model of the quadrotor is established and linearized with small disturbances to transform it into a state-space model suitable for MPC design. An MPC optimization controller is then constructed, with an objective function that minimizes state error and imposes an input energy penalty, while explicitly considering the system's input and state constraints. Simulation results demonstrate that this method exhibits good tracking accuracy and control smoothness for typical trajectory tracking tasks (such as circular and spiral trajectory tracking). Compared with traditional PID and LQR controllers, the proposed method significantly improves maximum error, mean square error, and interference rejection. This study provides an engineering-feasible optimization control framework for UAV trajectory control.

Peng, Fei, Tao, Zhong, Gao, Qiang, Jia, Bobo

Analysis of the Influence of Space Environmental on the Thermal Radiation Performance and Surplus of a Multilayer Insulation

2026-99-0575

7/10/2026

Thermal shock, space combined irradiation test, and humidity test were carried out on one type of multilayer insulation. We summarized and analyzed the change in solar absorptance and hemispheric emittance before and after the environmental test. At the same time, the thermal stability and vacuum pollution characteristics were investigated by thermal weightlessness test and thermal vacuum outgassing test. The results show that the change in thermal radiation performance before and after the environmental test is no more than 0.02, the heat resistance is 350 °C, TML is 0.50%, and CVCM is 0.05% at 135 °C. It is observed that the thermal radiation performance of the material is hardly degraded by thermal shock, and humidity and space combined irradiation. The multi-layer insulation shows good thermal radiation characteristics, thermal stability, and low space pollution characteristics.

Li, Weiyu, Liu, Yang, Li, Xiujie, Sun, Shu, Huang, Feiyu, Yang, Yaodong

Miner’s Safety Bot: An ESP32-Based Autonomous Mobile Mine Safety Monitoring System

2026-28-0116

2/12/2026

Mining operations are important to industrial growth, but they expose the mining workers to risk including hazardous gases, elevated ambient temperatures, and dynamic structural instabilities within underground environments. Safety systems in the past, typically based on fixed sensor networks or manual patrols, fall short in accurate hazard detection amidst shifting mine conditions. The proposed project Miner's Safety Bot advanced this paradigm by leveraging an ESP 32 microcontroller as a mobile platform that integrates gas sensing, thermal monitoring, visual inspection and autonomous obstacle avoidance. The system incorporates MQ7 semiconductor gas sensor to monitor real time carbon monoxide (CO), offering detection range from 5 to 2000 ppm with accuracy of 5 ppm. Temperature and humidity are monitored through DHT11 digital sensor, calibrated to ensure reliability across the harsh microclimates in mines. Navigation and autonomous movement are enabled by Ultrasonic Sensor (HC-SR04) with 3 mm accuracy level for obstacle detection, that is integrated into mobile chassis which is driven by L298N dual H-bridge motor drivers. The bot's orientation and sensor field of view are controlled by a servo motor. For visual inspection, ESP32-CAM module streams real time visuals from mine. Wireless data transmission uses the ESP32's inbuilt Wi-Fi to link sensor outputs to the Blynk IoT platform, that enables to monitor data remotely.

D, Suchitra, D, Anitha, Muthukumaran, Balasubramaniam, Mohanraj, Siddharth, Subash Chandra Bose, Rohan

Study of Drive Trace Indices and Their Correlation with CO ₂ in Chassis Dynamometer

2026-26-0517

1/16/2026

With introduction of Corporate Average Fuel Efficiency norms (hereafter referred as CAFÉ norms) in India, the manufacturers of all M1 Category vehicles (not exceeding 3,500kg GVW) must ensure that they comply with Annual Corporate average CO2 target as defined in regulation. Moreover, this target will become stricter at various stages in the coming years. Hence CO2 emissions are becoming one of the major focus parameters during vehicle development. There are several factors that can impact CO2 emissions during measurement in laboratory-based test cycles such as MIDC or WLTC. One such major factor is driving variations. Although speed and time tolerances are provided during the test (as part of AIS 137/AIS 175) to limit the variation, even within these tolerances, drive-related effects make significant contribution to test results variability. Monitoring and control of such variations is important to understand the true fuel economy potential of the vehicle. Drive Trace indices are standardized metrics that can be used to evaluate the driving variations. The aim of this study is to understand the different driving behaviors on drive indices and consequently on CO2. Drive indices such as Energy Rating (ER), Distance Rating (DR), Energy Economy Rating (EER), IWR (Inertial Work Rating), RMSSE (Root Mean Square Speed Error) defined in SAE J2951 document have been referred for this study. Multiple MIDC & WLTC emission test data have been used for evaluation of driving behavior. An attempt has been made to establish a correlation between the drive trace indices and CO2 (and fuel economy) in MIDC by using mathematical techniques similar to study done by JRC for WLTC.

ER, Shivram, Rawat, Vijaypal, Khandelwal, Vineet, Kumar, Arun, Malhotra, Jitendra

Development of a CNG-Diesel Dual Fuel Tractor with Mechanical Fuel Injection System

2026-26-0114

1/16/2026

Identification of renewable and sustainable energy solutions remains a key focus area for the engine designers of the modern world. An avenue of research and development is being vastly dedicated to propelling engines using alternate fuels. The chemistry of these alternate fuels is in general much simpler than fossil fuels, like diesel and gasoline. One such promising and easily available alternate fuel is compressed natural gas (CNG). In this work, a 3-cylinder, 3-liter naturally aspirated air-cooled diesel engine from the off-highway tractor application is converted into a CNG Diesel Dual fuel (CNG-DDF) engine. Part throttle performance test shows the higher NMHC and CO emissions in CNG-DDF mode which have been controlled by an oxidation catalyst in C1 8-mode emission test. A comparative performance shows that the thermal efficiency is up to 2% lower with CNG-DDF with respect to diesel. However, it has shown the benefit of 44% in Particulate Matter, while retaining the same NOx + NMHC levels as the baseline diesel engine. The cycle average CO emission has been found to increase by 6%. Average exhaust gas temperature has been found to be lower by up-to 54°C with CNG-DDF. To control the particulate and HC levels of the baseline NA engine, the CNG injection has been confined from 20% to 85% engine loads, across all engine speeds. The peak firing pressure and in-cylinder temperature are lower by ~3% and ~7%, and the SoC got retarded by max 4°CA with CNG-DDF which is in-agreement with drop in thermal efficiency. The outcome from the engine dyno level testing has been successfully validated through the tractor testing.

Choudhary, Vasu, Mukherjee, Nalini, Kumar, Sanjeev, Tripathi, Ayush, Nene, Devendra

Real Drive Emission Measurement on CEV Machinery- Study of Testing Challenges and Different Machine Duty Cycles

2026-26-0228

1/16/2026

To conduct RDE (Real-Drive Emission) test on CEV (Construction Equipment Vehicle), the first step is to study the requirements set forth in the regulation [1, 2] for data collection, post-processing of data and emission calculation along with certain requirements for vehicle operation. Conducting tests on CEV machines poses a different set of challenges compared to on-road vehicles, the major one being the placement of PEMS (Portable Emission Measurement Equipment) on the machine under test. No singular method or mechanism can be specified to suit all types of machinery, although certain guidelines can be set for best practices. The requirement of running the machine on an actual duty cycle or a reference duty cycle requires a thorough study of the intended machine operation and also awareness on the multi-functionality setups offered for such machines by manufacturers, before deciding on a duty cycle to run during actual emission testing. Measurement of emission components such as Carbon Monoxide (CO), Total Hydrocarbons (THC), Nitrogen Oxides (NOx) and Carbon Dioxide (CO2) is required along with Exhaust flow and ECU parameters like engine speed, torque (Actual, Friction, Reference), fuel flow and coolant temperature are required for conducting a valid test. Exploring the impact on emission values of different machine applications, machine duty cycles, environmental and geographical conditions is also of utmost importance to ensure robust engine calibration which will meet future conformity limits irrespective of these factors. Tests on same CEV machinery within same geographical and ambient conditions but under different duty cycle may have variation in emission results [3], this study will delve deeper into this impact of duty cycle on emission value.

Chauhan, Pratyush, Kulkarni, S D, More, Manoj, Joshi, Monal Vishwas

Brake Emission Testbed Automation and Control: Insights and New Developments

2026-26-0232

1/16/2026

A significant contributor to particle mass (PM) emissions originating from road transport are particles emitted from brakes, which in Europe are considered in the upcoming Euro 7 emission legislation. UN-GTR (United Nations Global Technical Regulation) no. 24 describes the methodology for measuring brake particle emissions in a test cell setting with a dynamometer, both in terms of PM and PN (particle number). A regulation-compliant test fulfills various quality criteria for different control parameters, which can often be met by applying different control strategies. In this study, we evaluate the effects of implementing different control strategies for torque applied to the brake by the dynamometer, as well as for sampling flow. Additionally, we discuss the cost-saving potential of increasing the automation degree of testing, as well as modifying existing testbeds to accommodate brake emission testing. The torque control strategies applied in this study did not influence PN or PM emissions. For mass-based sampling flow control, adjusting the flow according to momentary readings of pressure and temperature will lead to variation in isokinetic ratio. Conversely, setting constant values of pressure and temperature will lead to variation in volume flow through the cyclone. For realizing cost-saving potential, we present two new technical solutions: AVL PM Sampler xChange for automating the PM measurement, and AVL Brake Emission 3rd Party Integration platform for integrating AVL brake emission measurement instruments into already existing testbed infrastructures, that are only missing the instrumentation (e.g., a converted engine dynamometer).

Martikainen, Sampsa, Weidinger, Christoph, Huber, Michael Peter

Methodology to Model EMI from E-motors and Controller in the Frequency Range from 30 to 200 MHz

2026-26-0524

1/16/2026

As EMC testing for E-motor drives gains significance due to the involvement of high-frequency switching and high current systems. The radiated emission testing as per CISPR 25 necessitates utilizing an EMC-proof dynamometer to load the E-motor drives during EMC testing inside EMC chamber, which presents a highly complex and expensive testing arrangement. This paper outlines a detailed approach for modelling radiated emission without the usage of such a complex arrangement, by measuring conducted high-frequency currents on the DC and AC lines of motors and MCUs while utilizing a non-EMC-proof motor dynamometer under loaded conditions. In this paper the measurements are conducted in the frequency range of 30 MHz to 200 MHz where usually more issues due to switching noise occurs. The developed model facilities early stage diagnosis of potential EMC issue, enabling mitigation strategies before motor EMC testing. Validation of the method was performed through experimental comparison with conventional 1 m radiated emission measurement in semi anechoic chamber. This approach offers a practical and cost-effective solution for EMC motor testing at higher loading conditions in pre-compliance evaluation according to CISPR 25 standard.

M, Gokul, Patel, Jinay, Mulay, Abhijit B

WITHDRAWAL NOTICE

2026-26-0475.01

1/16/2026

Legislative Framework and Emission Testing using PEMS for NRMM (Non-Road Mobile Machinery) in India: A Technological Perspective

2026-26-0139

1/16/2026

Emission Regulations for NRMM in India have evolved significantly over past two decades. India has progressively adopted stricter standards to align with best practices carried out globally for curbing air pollution. The latest regulations have introduced stringent caps on nitrogen oxides (NOx), and other emission pollutants, ensuring compliance with environmental sustainability goals. Future legislative frameworks are expected to impose even more rigorous emission limits, while incorporating real-world emission monitoring. This will require powertrain manufacturers to integrate advanced after-treatment systems and adopt cleaner combustion technologies to meet compliance standards. To validate compliance with these stringent limits, rigorous testing methodologies are employed. Portable Emission Measurement Systems (PEMS) have become a crucial tool for real-world emission assessment. PEMS technology allows for on-road and field testing of NRMM under actual operating conditions, providing a comprehensive analysis of pollutant levels. The setup consists of advanced gas analyzers and data acquisition systems installed directly on the machinery. These systems continuously measure CO, CO2, nitrogen oxides (NOx), and other emission pollutants, ensuring precise monitoring. The installation involves strategic placement of sensors and exhaust sampling systems, allowing real-time data collection. The testing process involves preconditioning the equipment, executing a predefined test-cycle under operational conditions, and analyzing the collected emission data against regulatory standards. This methodology ensures that emission control strategies are effectively validated in real-world applications. Post-processing of test data is critical for interpreting results and assessing compliance. Advanced data analytics techniques are used to refine raw measurements, filter anomalies, and generate comprehensive emission reports. In this paper, as we go forth, focus has been placed on the real time application of PEMS system for CEV/TREM, covering important points like setup installation, components involved, technology used, test procedure criterion based on emission norms, data accumulation and analysis, report generation, etc. And all this is done using the indigenous state of the art AVL PEMS setup.

Rastogi, Aadhar, Garg, Varun, Ragot, Nicolas

Ultra-Lightweight, Multispectral, High-Resolution Imaging for Orbital Intelligence and Civilian Missions

TBMG-54192

11/18/2025

Elbit Systems Haifa, Isreal

Integration of a Compact 4-Stroke Engine into a Model Vehicle with Dynamic Emission Analysis on a Small Chassis Dynamometer

2025-32-0074

11/3/2025

The increasing importance of reducing emissions and improving the efficiency of internal combustion engines extends not only to applications in large vehicles, but also to small drive systems. This study focused on the implementation of a compact 4-stroke engine in a model vehicle and on dynamic emission tests carried out with a specially developed test rig. The aim was to investigate the integration of small combustion engines into model platforms and to evaluate their emission behavior under transient conditions. The 4-stroke engine was carefully selected and adapted to the physical and operational conditions of the model vehicle. A test rig with a small roller dynamometer was developed to simulate real driving cycles and enable dynamic measurement of emissions. To optimize oil emissions, an online mass spectrometer was used to analyze the effects of lubricant composition and hardware variations, such as different piston ring designs, on emission behavior. High-resolution measuring devices recorded transient emissions and provided insights into the engine’s behavior at different loads and speeds. The results demonstrated that small 4-stroke engines can be effectively integrated into model vehicles while providing acceptable performance and emission levels. However, dynamic testing showed significant emission spikes during transient operation, particularly in relation to oil emissions, highlighting the challenges of controlling emissions during acceleration and deceleration phases. These results underline the importance of optimizing combustion control strategies, lubricant formulations and hardware design for small engines. This work makes valuable contribution to the field of miniature propulsion systems and provides a basis for future research to improve the environmental performance of small internal combustion engines.

Gohl, Marcus, Moriyoshi, Yasuo, Kuboyama, Tatsuya, Arakawa, Hitomu

Ultralightweight Emission Measurement Systems for Motorcycles: Accuracy and Practicality in RDE Testing

2025-32-0011

11/3/2025

Real Driving Emission (RDE) testing for motorcycles presents unique challenges due to the motorcycle’s lightweight construction, limited mounting space, and sensitivity to added mass and aerodynamic drag. Full-functional automotive Portable Emission Measurement Systems (PEMS), while highly accurate, are often impractical for two-wheelers as their weight and size can alter driving resistances, fuel consumption, and emission profiles, but also complicate installation and probably effect the drivability of the vehicle. To address these limitations, lightweight alternatives such as Mini-PEMS and ultralightweight alternatives such as Sensor-based Emission Measurement Systems (SEMS) offer compact, low-power solutions tailored for small vehicles. SEMS are typically equipped with lower cost sensors and low-tech gas conditioning systems compared to PEMS. Due to this these systems may not meet regulatory homologation requirements. Nevertheless, they provide justifiable accuracy for many real-world applications. This paper explores the working principles and sensor technologies used in Mini-PEMS and SEMS, highlighting key trade-offs between size reduction, energy efficiency, and measurement precision. Mini-PEMS reduce complexity by employing analyzers with a minimalized conditioning system. SEMS, moreover, leverages smart sensor integration to deliver real-time emission assessments with minimal impact on vehicle dynamics. To assess their reliability, Mini-PEMS and SEMS are evaluated against laboratory-, homologation-grade equipment under controlled conditions. Accuracy analyses reveal specific limitations, but also demonstrate that these systems provide sufficiently robust data for many practical applications. By balancing accuracy with real-world feasibility, Mini-PEMS and SEMS offer a viable path for emission testing in scenarios where full-scale PEMS are impractical. Their adoption could expand the scope of RDE assessment, particularly for low-powered two-wheelers, ultimately supporting more accessible and widespread emission monitoring.

Schurl, Sebastian, Lienerth, Peter, Japs, Leonid, Schroeder, Matthias, Schmidt, Stephan, Kirchberger, Roland

RDE Testing of Small Motorcycle in Indian Road Conditions and Study the Impact of Instrumentation on Emission and Fuel Economy

2025-32-0075

11/3/2025

This paper presents measurement results of emissions and fuel economy on real-world driving of two-wheelers in India using a state-of-the-art FTIR PEMS technology. The study aimed to characterize the emissions profiles of a small motorcycle under typical Indian driving conditions, including congested urban traffic and highway driving. This is the continuation of the study conducted previously on bigger motorcycle using gas analyzer [1], with necessary adaptations to suit the specific conditions of Indian roads and traffic. Key parameters such as NOx, CO, CO2 and Fuel consumption were measured during real-world driving cycles and comparison is done with standard WMTC emission testing cycle. The findings of this study provide valuable insights into the actual on-road emissions of two-wheelers in India, which can be used to develop more accurate emission models and guide the development of cleaner and more efficient two-wheeler technologies. Key Considerations: Specifics of Indian Driving Conditions: Emphasize the unique challenges posed by Indian traffic, such as stop-and-go traffic, frequent idling, and high ambient temperatures. Data Analysis and Interpretation: Discuss how the data was analyzed and the statistical methods used to assess the significance of the findings. Comparison with Laboratory Tests: Compare the real-world emission results with those obtained from laboratory tests to assess the accuracy of current regulatory testing procedures. Policy Implications: Discuss the implications of the findings for future emission regulations and the development of cleaner two-wheeler technologies in India. This abstract provides a concise overview of the research and highlights the key findings and their significance. The study is also conducted and compiled to show the effect of measurement devices on the actual emissions and fuel economy of the vehicle tested in standard WMTC emission testing cycle inside the lab conditions.

Agrawal, Rahul, Jaswal, Rahul, Yadav, Sachin

Achieving Euro 7 Compliance: Cost-Effective Brake Wear Particle Emissions and Performance with FNC-Smart ONC® GCI Rotors

2025-01-0332

9/15/2025

Advanced ferritic nitrocarburizing process combined with a specialized post-oxidation treatment described as FNC + Smart ONC® [1] is developed for brake rotor applications. The process can be applied to standard grey cast iron brake rotors, significantly reducing PM 10 emissions to levels below the Euro 7 limits for most vehicles equipped with at least some recuperative braking capabilities, all without compromising performance. Finished grey iron brake rotors, ferritic nitrocarburized and post oxidized were evaluated according to several industry standards. The standards include SAE J2707B (Block Wear Test including Highway) [2], GRPE-90-24 Rev.1 Emission Test (Full WLTP Brake Cycle 6 Times) [3], and SAE J2522 (AK-Master Performance) [4]. Nitrocarburized post oxidized brake rotors were compared to untreated grey iron rotors exposed to several friction materials. Ferritic nitrocarburizing and post oxidation addresses the issue of corrosion, which is particularly relevant for brake rotors that experience less use in vehicles with recuperative braking systems. Improved corrosion performance of ferritic nitrocarburizing and post oxidation could potentially eliminate the need for the conventional practice of painting rotors. Corrosion performance was validated by conducting cyclic corrosion according to SAE J2334 (Cyclic Corrosion, 36 cycles) [5]. A reduction in brake emissions by 50 percent was achieved for existing vehicles without recuperative braking systems.

Winter, Karl-Michael, Holly, Mike

AeroSolfd: Advancing Air Quality through Retrofitted Gasoline Particulate Filters – Insights from Laboratory and Real-World Evaluations

2025-24-0088

9/7/2025

This article details the experimental and testing activities of the EU project AeroSolfd, with a particular focus on the project's efforts to reduce combustion-based nanoparticle emissions in exhaust gases for the European fleet of vehicles by developing a GPF retrofit solution. The technical activities undertaken the process of developing such a retrofit are examined in this article. The findings illustrate the viability of reducing nanoparticle levels in gasoline-powered vehicles with the utilization of appropriate GPFs. For this purpose, in addition to a fleet, four vehicles were examined in great detail and underwent the process of obtaining component approval for the particulate filter. The vehicles were measured in a preliminary state, then following the installation of the GPF, and subsequently after several months of continuous field operation. A total of four vehicles were selected for evaluation as a representative subgroup of a larger test fleet of vehicles in the project. These four vehicles were subjected to a series of assessments, including measuring the emissions on a chassis roller test bench and in real-drive experiments with portable emission measurement equipment. The gaseous and nanoparticle emissions were examined in each of these two test cases, and the variants with and without a particle filter as well as the variants before and after the endurance run. Preliminary findings indicate that the retrofitting of gasoline vehicles with minimal modifications can yield notable benefits besides the reduction in air pollution, particularly in the form of nanoparticles.

Engelmann, Danilo, Mayer, Andreas, Comte, Pierre, Rubino, Lauretta, Larsen, Lars

DLR Tire and Road Wear Particle Emission Testing Methodology–Collection System Influence and Repeatability Assessments

2025-24-0092

9/7/2025

Tire and road wear particles (TRWP) have emerged as air quality hazardous matters and significant sources of airborne microplastic pollution, contributing to environmental and human health concerns. Regulatory initiatives, such as the Euro 7 standards, emphasize the urgent need for standardized methodologies to quantify TRWP emissions accurately. Despite advancements in measuring tire abrasion rates, critical gaps persist in the characterization of airborne TRWP, particularly regarding the influence of collection system design and influencing parameters on measurement accuracy and repeatability. This study addresses these challenges by designing a controlled methodological framework that aims to minimize the influencing effects and ensure comparability in TRWP emission quantification results. At the German Aerospace Center (DLR) dynamometer testbench in Stuttgart, Germany, a methodical framework was established to ensure the repeatability and comparability of TRWP measurements, incorporating standardized tire testing conditions and particulate matter sampling methodologies. The results indicated that the DLR® housing-based system with an encapsulated tire exhibited higher particle concentrations in fine and ultrafine fractions compared to the nozzle-based system. Statistical analyses following ISO standards confirmed that the DLR® housing system demonstrated higher measurement consistency, with lower deviations in repeated tests. In contrast, the nozzle system showed higher deviations, particularly in the PM10 fraction (i.e., particles with aerodynamic diameter less than 10 μm), suggesting potential particle losses and lower collection efficiency. These findings emphasize the importance of designing measurement methodologies that minimize the influence of external factors and improve the repeatability of TRWP characterization. By establishing a standardized and comparable framework that isolates tire-road interaction effects from environmental and surface variability, this study enhances the accuracy of TRWP emission measurements. The proposed methodology aims to serve as a robust foundation for regulatory frameworks, offering valuable insights into the optimization of current TRWP measurement techniques.

Celenlioglu, Melis Seren, Epple, Fabius, Reijrink, Nina, Löber, Manuel, Reiland, Sven, Vecchi, Roberta, Philipps, Franz

Aircraft Fuel System and Component Icing Test

ARP1401C (Current)

6/27/2025

This SAE Aerospace Recommended Practice (ARP) covers a brief discussion of the icing problem in aircraft fuel systems and the different means that have been used to test for icing. Fuel preparation and icing test procedures for aircraft fuel systems and components are proposed herein as a recommended practice to be used for fixed wing and rotary-wing aircraft within their operational environment. This ARP mostly addresses aircraft fuel system level testing and provides a means to address the requirements of FAR 14 CFR § 23.951(c), § 25.951(c), § 27.951(c), and § 29.951(c). In the context of this ARP, the engine and the auxiliary power unit (APU) are not considered to be components of the aircraft fuel system. However, some of the methods described in this document can be applied to the engine, APU, and other aircraft (system or component level) icing tests. This revision does not completely address new developments in ice accretion and release resulting from internal flow in tubing (see 2.3.6). This will be addressed in a different document when more experimental data is available.

AE-5A Aerospace Fuel, Inerting and Lubrication Sys Committee

Experimental Analysis of Performance and Durability Using Ethanol 27% Fuel Blend in a Turbocharged Gasoline Direct Injection Engine

2025-01-0245

6/16/2025

India aims to achieve 20% ethanol blending (E20) in petrol by 2025 under its National Biofuels Policy to reduce carbon emissions, enhance energy security, and support the agricultural economy. Building on this, E27 (27% ethanol in gasoline) is being evaluated as an advanced mid-level blend to further lower greenhouse gas emissions and reduce reliance on fossil fuels. This study investigates the performance, emissions, and combustion characteristics of a turbocharged gasoline direct injection (TGDI) engine using E27 fuel over 20,000 km in real-world driving conditions, as part of a broader research program accumulating over 100,000 km across multiple vehicle categories. Key findings indicate that E27 achieves an optimal balance of emissions reduction and performance, with NOx and THC emissions decreasing by 12% and 5%, respectively, compared to E10, while CO and CO₂ levels remained stable, reflecting ethanol’s oxygenation effect and lower carbon intensity. Power output and acceleration improved slightly due to ethanol’s higher-octane rating and improved combustion efficiency. Oil degradation and wear remained within acceptable limits, confirming E27's suitability for regular use without requiring engine modifications. The findings suggest that E27 blended fuel has potential and can significant future ethanol adoption strategy, which will also supporting its 2030 carbon reduction targets. Further research should focus on optimizing calibration in engine for different ethanol blends as the current study has focused on E10 compliant vehicle’s long-term durability, and performance of the with higher fuel blends aligning with real time usage pattern.

D R, Vigneshwar, Bhakthavachalu, Vijayabaskar, Muralidharan, M.

A Satellite to Detect Short Gamma-Ray Burst Emissions

25AERP06_09

6/1/2025

Physicists at the Naval Research Laboratory are collaborating with several universities throughout the U.S. to develop a small satellite that will detect the emission of short gamma-ray bursts. U.S. Naval Research Laboratory, Washington D.C. The U.S. Naval Research Laboratory (NRL), in partnership with NASA's Marshall Space Flight Center (MSFC), has developed StarBurst, a small satellite (SmallSat) instrument for NASA's StarBurst Multimessenger Pioneer mission, which will detect the emission of short gamma-ray bursts (GRBs), a key electromagnetic (EM) signature that will contribute to the understanding of neutron star (NS) mergers. NRL transferred the instrument to NASA on March 4 for the next phase, environmental testing. From there, the instrument will be integrated onto the spacecraft bus, followed by launch into Low Earth Orbit in 2027. StarBurst will be installed as a secondary payload via the Evolved Expendable Launch Vehicle Secondary Payload Adapter Grande interface with a mission duration of one year, with the option of extension.

Simulation of Pass-by Fan Noise Emissions and Advancing Test Regulations for Heavy-Duty Electric Vehicles

2025-01-0086

5/5/2025

The rapid adoption of electric vehicles (EVs) necessitates updates to the automotive testing standards, particularly for noise emission. This paper examines the vehicle-level noise emission testing of a Nikola Class 8 hydrogen fuel cell electric semi-truck and the component-level noise emission testing needed to create a predictive simulation model using Wave6 software. The physical, component-level noise emission testing focused on individual cooling fans in a semi-anechoic chamber to assess their isolated noise contributions. With this data, an initial model was developed using spatial gradient statistical energy analysis, which successfully predicted pass-by noise levels based on varying fan locations and speeds. Real-world pass-by testing confirmed the model's accuracy across different cooling fan speeds. By leveraging advanced simulation techniques, engineers aim to enhance the accuracy and reliability of pass-by noise predictions through cost-effective studies of architectural changes before implementation. As EVs produce noise differently from internal combustion engine (ICE) vehicles, current industry standardized tests inadequately capture their full noise profiles. This paper highlights the need for regulatory updates to ensure effective pass-by testing for Class 8 electric semi-trucks and other EVs to adequately address their unique noise characteristics. Future work aims to refine the model and tackle issues with existing standards that do not accommodate EV architecture.

Passador, Stephen, Woo, Sangbeom, Liu, Ting-Wei, De La Vega Alonso, Gerardo, Kim, James

RDE Methodology Development for Motorcycle Emissions Assessment

2024-32-0073

4/18/2025

The transfer of conditions and regulations for RDE testing from passenger cars to motorcycles is a non-trivial undertaking. Motorcycles exhibit significant differences in construction and usage compared to cars, necessitating a distinct set of requirements for equipment and methodology. Currently available PEMS are hindered by their relatively large size and weight due to the embedded measurement technology and external power supply. The weight of, at least 50kg, poses a substantial additional load, leading to a deviation and, on average, higher load collective of the engine during RDE measurement rides. Beyond these structural parameters, the actual propulsion system and subsequent exhaust system introduce another challenge when employing PEMS on motorcycles. An unfavorable combination of the ratio of engine displacement to the volume of the exhaust system and long or unequal ignition intervals leads to pulsations, which has a considerable impact on the differential pressure-based measurement method in the EFM. To tackle these challenges, this paper presents the verification of a lightweight off-the-shelf PEMS and an EFM tailored for motorcycles. The verification process of the PEMS is conducted on a state-of-the-art two-wheeler chassis dyno, addressing different L-category subclasses (A1 - A3). This verification ensures the reliability and accuracy of the developed methodology across a range of motorcycle types and engine configurations. Furthermore, the paper provides a detailed RDE measurement example, showcasing the practical application of the developed methodology in real-world scenarios. The mounting platform for motorcycles is described, considering the diverse design configurations and exhaust layouts encountered in various motorcycle categories. Additionally, the integration of complementary devices, such as OBD loggers, enhances the capabilities of the PEMS for comprehensive emissions monitoring during RDE tests. The RDE example illustrates the use of the lightweight PEMS in capturing emissions data from a motorcycle under diverse operating conditions, validating its utility for regulatory compliance and environmental impact assessment. In conclusion, this paper contributes to the advancement of RDE methodology for motorcycles by addressing the unique challenges posed by their diverse engine configurations and usage patterns. The development of the methodology including the verification process establishes a robust framework for real-drive emissions testing of LVs.

Schurl, Sebastian, Keller, Stefan, Lankau, Mathias, Hafenmayer, Christian, Schmidt, Stephan, Kirchberger, Roland

Meteorological Aspects of the Operational Design Domain – Enhancing Road and Rail Safety and Efficiency through Integrated Wind, Weather, and Motion Sensing Technology

2025-01-8100

4/1/2025

As automotive technology advances, the need for comprehensive environmental awareness becomes increasingly critical for vehicle safety and efficiency. This study introduces a novel integrated wind, weather, and motion sensor designed for moving objects, with a focus on automotive applications. The sensor’s potential to enhance vehicle performance by providing real-time data on local atmospheric conditions is investigated. The research employs a combination of sensor design, vehicle integration, and field-testing methodologies. Findings prove the sensor’s capability to accurately capture dynamic environmental parameters, including wind speed and direction, temperature, and humidity. The integration of this sensor system shows promise in improving vehicle stability, optimizing fuel efficiency through adaptive aerodynamics, and enhancing the performance of autonomous driving systems. Furthermore, the study explores the potential of this technology in contributing to connected vehicle ecosystems and smart traffic management. The integration of such advanced sensing capabilities represents a significant step towards safer, more efficient, and environmentally responsive automotive systems.

Feichtinger, Christoph Simon

High-Efficient and Cost-Effective Three-Way Catalyst Substrate Design for Plug-in Hybrid Electric Vehicle

2025-01-8528

4/1/2025

China 6b regulation was fully implemented since July 2023 with very strict emission standards for HC, NMHC, NOx, and CO. The country is now also in the process of developing China 7 regulation, which will perhaps impose even stricter emission limits and extra criteria pollutants including NH3. Moreover, increasingly strict fuel consumption regulation has been implemented as well and it is highly possible that greenhouse gas emission limits will be included in the China 7 regulation. With the hybrid technology innovation, PHEVs are effective in fuel economy and emission reduction, which are favored by manufacturers and consumers, and leading to a rapid increase in market share. Through the optimization of hybrid architecture and the synergy of electric motors, the operating conditions of the hybrid engine have been optimized, making it more stable and avoiding extreme engine operating conditions compared to traditional ICE, which also provides possibilities for optimizing the after-treatment system design to achieve low cost and high efficiency at the same time. In this study, engine operating conditions and engine out emissions of a PHEV were analyzed through vehicle testing with WLTC cycle in lab. Emission tests were conducted using different catalyst systems to study the impact of different substrate design options including low mass Corning® FLORA® substrates with higher cell density on gaseous pollutant emissions. As a byproduct of secondary reactions on catalysts, the generation of NH3 is closely related to catalyst efficiency. This study also investigated the characteristics of NH3 emissions and proposed appropriate design to reduce NH3 emission. Additionally, the influence of thermal aging conditions on catalyst conversion efficiency was studied to explain the correlation between anti-ageing performance and the substrate design.

Wang, Jiming, Li, Chunbo, Feng, Xiangyu, Chen, Xiaolang, Boger, Thorsten, Tian, Lichen, Hu, Xianli, Zeng, Jun, Tian, Tian, Gao, Bojun, Li, Dacheng, Liu, Shicheng, Jiang, Fajun

Experimental Analysis of Soot and NOx Mitigation during Energy-Buffered Diesel Engine Transients

03-18-02-0014

3/24/2025

Transient operation of a diesel-fueled compression ignition engine will produce significant levels of engine-out criteria pollutants such as NOx and soot emissions due to turbocharger lag. Conventional pollutant mitigation strategies during tip-ins (large increases in load) are constrained by the soot–NOx trade-off—strategies that mitigate soot/NOx emissions often result in an increase in NOx/soot emissions. Hybridization offers the ability to use an e-machine as an energy buffer during a tip-in, allowing the engine to tip-in slower to give the turbocharger time to spin up and provide the necessary amount of air for clean, high-load operation. In this work, an in-line six-cylinder 12.8 L Detroit Diesel DD13 engine was used to study the impact of slowing the torque ramp rate of a tip-in on the effectiveness of transient emission reduction strategies for turbocharged diesel engines, including exhaust gas recirculation (EGR) valve closing, start of injection retard, and the air–fuel ratio threshold with which these emissions reduction techniques are activated. The experiments showed that smoke emissions can be reduced without a corresponding increase in NOx emissions by slowing the tip-in. It was also found that the NOx penalty of reducing EGR flow was attenuated with a slowed tip-in, enabling more aggressive smoke mitigation strategies. Overall, it was shown that a combination of slowing a B25-B75 (from the 13-mode supplemental emissions test) tip-in and reducing EGR flow during the tip-in, the smoke emissions during the tip-in could be reduced by approximately 50% while reducing NOx emission by approximately 4%.

Gainey, Brian, Datar, Aditya, Bhatt, Ankur, Lawler, Benjamin

Emission Characteristics of TCR Diesel Fuels in Comparison to Diesel Fuels Derived from other Sources

2024-01-4289

11/5/2024

In this work we demonstrate the influence of different refined TCR refining diesel fuels on emission, power and efficiency in comparison to reference Diesel fuel (homologation fuel for Euro 6 emission testing), hydrotreated vegetable oil (HVO) and a blend of poly(oxymethylene)dimethyl ether (OME3) with reference Diesel. The emission characteristics of such TCR fuels used in a production type Diesel engine with modern common rail system has up to now not been tested. The comparison was performed at an engine test bench equipped with a Hatz 4H50 TIC direct injection common rail Diesel engine. For different engine operation points exhaust gas emissions and particulate matters were measured and the results analyzed.

Seeger, Jan, Taschek, Marco

Catalyzed Gasoline Particulate Filter Performance from Fresh to Full Useful Life

2024-01-4311

11/5/2024

The gasoline particulate filter (GPF) represents a durable solution for particulate emissions control in light-duty gasoline-fueled vehicles. It is also seen as a viable technology in North America to meet the upcoming US EPA tailpipe emission regulation, the proposed “Multipollutant Rule for Model Year 2027”. The goal of this study was to track the evolution of tailpipe particulate emissions of a modern GTDI light duty vehicle under typical North American mileage accumulation; from a fresh state to 4000-mile, and finally to its full useful life of 150,000-miles. For this purpose, a production TWC + GPF after-treatment system was installed in place of the T3B85 TWC-only system. Chassis dyno emissions testing was performed at the pre-determined mileage points with on-road driving conducted for the necessary mileage accumulation. This report will show the outstanding filtration durability and enhanced particulate control and of the current GPF technology all the way to 150,000 miles for the typical North American application. The report will also demonstrate that a coated CC2 GPF solution is an acceptable substitution for a flow through TWC catalyst for gaseous emissions performance, using an older 1st generation GPF washcoat technology without system optimization efforts. Noting that the investigation is an extension of previously reported results from the GPF performance from 0 to 4000-miles which characterized the early life evolution of tailpipe particulate emissions, specifically mass (PM) and number (PN).

Craig, Angus, Warkins, Jason, Beattie, James, Nipunage, Sanket, Moser, David, Day, Ryan, Banker, Vonda

Air Cycle Air Conditioning Systems for Air Vehicles

AS4073B (Current)

10/3/2024

This SAE Aerospace Standard (AS) defines the requirements for air cycle air conditioning systems used on military air vehicles for cooling, heating, ventilation, and moisture and contamination control. General recommendations for an air conditioning system, which may include an air cycle system as a cooling source, are included in MIL-E-18927E and JSSG-2009. Air cycle air conditioning systems include those components which condition high temperature and high pressure air for delivery to occupied and equipment compartments and to electrical and electronic equipment. This document is applicable to open and closed loop air cycle systems. Definitions are contained in Section 5 of this document.

AC-9 Aircraft Environmental Systems Committee

Handling, Packaging, and Conditioning of Materials and Components Used in Automotive Interiors for Emissions Testing

J2989_202409 (Current)

9/27/2024

This SAE Recommended Practice is intended for stakeholders of the automotive industry that are conducting emission testing on materials, parts, or components used in automotive interiors. Testing methods may specifically define the handling and packaging conditions for the material to be analyzed. In these cases, follow the method as closely as possible. Use this document as a guide where the protocol for handling and packaging the samples between production and testing may be undefined or ambiguous.

Volatile Organic Compounds

Aerospace - General Requirements for Hydraulic Fuse - Quantity Measuring

AS5466 (Current)

6/24/2024

This specification establishes the design, performance, and test requirements for hydraulic quantity measuring fuses intended to be used for hydraulic circuit protection.

A-6C5 Components Committee

Technical Challenges with on Board Monitoring

2024-01-2597

4/9/2024

The proposed Euro 7 regulation includes On Board Monitoring, or OBM, to continuously monitor vehicles for emission exceedances. OBM relies on feedback from existing or additional sensors to identify high emitting vehicles, which poses many challenges. Currently, sensors are not commercially available for all emissions constituents, and the accuracy of available sensors is not capable enough for in use compliance determination. On board emissions models do not offer enough fidelity to determine in use compliance and require new complex model innovation development which will be extremely complicated to implement on board the vehicle. The stack up of multi-component deterioration leading to an emissions exceedance is infeasible to detect using available sensors and models. An assessment of limitations and measurement accuracy for sensors or models including oxides of nitrogen (NOx) sensors under a variety of operating conditions, ammonia (NH3) sensing, and particulate matter (PM) sensing is provided. This paper also reviews what is being promulgated elsewhere in regard to using on-board sensors or portable emissions measurement systems (PEMS) to directly measure pollutants such as the California Air Resources Board (CARB) “Real Emissions Assessment Logging (REAL) NOx Tracking” system and in-use on-road emissions testing requirements. Considering the aforementioned technical challenges with OBM, we will offer practical measures to identify significant excess emissions and detect tampering of the emission system. We will consider the use of already available designs including statistical analysis of diagnostic results and other solutions that can be implemented quickly. One such solution is closing the gap to existing US/CARB On Board Diagnostic (OBD) requirements. We will also discuss the challenges of defining standardized data parameters to support the proposed implementation timing.

Funk, Sarah, Potter, Janean, Pruski, Erika

Exhaust Slip-Stream Sampling System for Aftertreatment Device Testing

2024-01-2703

4/9/2024

Design, testing, and implementation of new aftertreatment devices under various engine operating conditions is necessary to meet increasingly stringent regulatory mandates. One common aftertreatment device, the catalytic converter, is typically developed at a reduced scale and tested using predefined fluid compositions sourced from bottle gases and can undergo both species and temperature cycling in addition to steady-state testing. However, these bench-top conditions may differ from real-world operation in terms of flow-rates, species composition, and temperatures experienced. Transitioning from small-scale bench-top testing to full-scale engine applications requires larger monoliths that therefore have a significant amount of catalyst slurry to be washcoated, which increases cost and fabrication time. Being able to experience realistic emission streams under scaled flowrates would allow for a physically smaller catalyst testing at matched space velocities resulting in faster, more cost-effective determination of aftertreatment device effectiveness. This work documents the design and performance of an intermediary-scale (5-50 SLPM) setup to aid in the catalyst testing process. This is accomplished using a secondary exhaust branch to flow a variable percentage of exhaust from the main branch. The system siphons exhaust via a slip-stream approach driven by a venturi ejector, which is commonly used in automotive applications to dilute samples for emissions analysis. Instead, the pre-diluted flow from the ejector is routed through the catalyst, where post catalyst emissions testing occurs. The system is evaluated under a range of engine operating conditions with varied equivalence ratio and intake pressures to affect exhaust out temperatures / catalyst inlet temperature which is critical for testing catalyst activation. Emissions are recorded in both the main and secondary branch with no aftertreatment device installed to verify compositional parity. Initial results show that the two branches produce self-similar engine-out emissions, but with the ability to scale flow and modulate temperature through the secondary catalyst testing branch.

Loprete, Jason, Ristow Hadlich, Rodrigo, Sirna, Amanda, Assanis, Dimitris, Mon, Tala, Kyriakidou, Eleni

Full-Scale CFD Prediction of the Performance of Advanced After-Treatment Systems during Severe RDE Test Cycle

2024-01-2624

4/9/2024

Air pollution is a significant environmental issue, and exhaust emissions from internal combustion engines are one of the primary sources of harmful pollutants. The transportation sector, which includes road vehicles, contributes to a large share of these emissions. In Europe, the latest emission legislation (Euro 7) proposes more stringent limits and testing conditions for vehicle emissions. To meet these limits, the automotive industry is actively developing innovative exhaust emission-control technologies. With the growing prevalence of electrification, internal combustion engines are subject to continuous variations in load and engine speed, including phases where the engine is switched off. The result is an operating condition characterized by successive cold starts. In this context, the challenge in coping with the emission limits is to minimize the light-off time and prevent fast light-out conditions during idling or city driving. This goal can be achieved by reducing heat losses and thermal inertia, and suitably exploiting electrically heated solutions to maintain the catalyst inlet temperature at the desired level. In addition, issues related to mechanical durability must be considered, to allow the long-term life of the catalyst during continuous heat-up and cool-down cycles under severe flow conditions. This paper aims to contribute to the development of an efficient after-treatment system, designed specifically for passenger cars, and to provide insights into the optimization of the catalyst design. This study employed advanced computational fluid dynamics (CFD) simulations to investigate the performance of a catalyst under a real driving emission cycle (RDE). A close-coupled configuration in a turbocharged gasoline engine was investigated. A detailed analysis of the external region of the substrate, which is critical because the temperatures are lower due to the heat transfer towards the environment, allows the identification of a suitable configuration. Flow conditions with post-turbo swirled flow along with the actuation of the wastegate valve were considered, and their impact on the pollutant abatement efficiency of the catalyst was evaluated. A CFD framework has been implemented based on the open-source OpenFOAM code, modeling the complex phenomena of heat and mass transfer and catalytic reactions occurring in the substrate. Measured data of pollutant emissions and gas temperatures have allowed the validation of the CFD predictions and the optimization of the after-treatment system to limit the heat losses and reduce the pollutants emitted in the atmosphere during a real driving emission test cycle.

Sartirana, Andrea, Montenegro, Gianluca, Della Torre, Augusto, Onorati, Angelo, Pace, Lorenzo, Zaldua-Moreno, Naroa

Comprehensive Thermal Modeling and Analysis of a 2019 Nissan Leaf Plus for Enhanced Battery Electric Vehicle Performance

2024-01-2403

4/9/2024

With the increasing demand for Battery Electric Vehicles (BEVs) capable of extended mileage, optimizing their efficiency has become paramount for manufacturers. However, the challenge lies in balancing the need for climate control within the cabin and precise thermal regulation of the battery, which can significantly reduce a vehicle's driving range, often leading to energy consumption exceeding 50% under severe weather conditions. To address these critical concerns, this study embarks on a comprehensive exploration of the impact of weather conditions on energy consumption and range for the 2019 Nissan Leaf Plus. The primary objective of this research is to enhance the understanding of thermal management for BEVs by introducing a sophisticated thermal management system model, along with detailed thermal models for both the battery and the cabin. These models are seamlessly integrated into a 2019 Nissan Leaf Plus BEV model developed in Autonomie, allowing for a holistic assessment of the influence of weather conditions on the driving range. The proposed model encompasses a mono-zonal model for the cabin, providing estimations of cabin temperature, humidity, and thermal requirements. Additionally, a battery thermal model for pouch-type cells, employing a 2D discretization approach with a nodal framework, is presented to predict battery temperature dynamics. Furthermore, a comprehensive thermal management system is integrated into the model, featuring a vapor compression cycle equipped with a PTC resistor. The study leverages these developed models within the Simulink framework and utilizes the Autonomie Software for rigorous evaluation of energy consumption and driving range. Various driving cycles and a range of ambient temperatures (-18°C, -7°C, 22°C, and 35°C) are considered in the analysis. To validate the models, the study draws upon experimental data collected from a 2019 Nissan Leaf subjected to extreme temperature conditions in the Environmental Test Cell at Argonne National Laboratory.

Al Haddad, Rabih, Mansour, Charbel, Kim, Namdoo, Seo, Jigu, Nemer, Maroun

Evaluation of Uncoated Gasoline Particulate Filter Performance for US EPA MY27+ Particulate Mass Emissions Regulation

2024-01-2383

4/9/2024

The gasoline particulate filter (GPF) represents a practical solution for particulate emissions control in light-duty gasoline-fueled vehicles. It is also seen as an essential technology in North America to meet the upcoming US EPA tailpipe emission regulation, as proposed in the “Multi-pollutant Rule for Model Year 2027”. The goal of this study was to introduce advanced, uncoated GPF products and measure their particulate mass (PM) reduction performance within the existing US EPA FTP vehicle testing procedures, as detailed in Code of Federal Regulations (CFR) part 1066. Various state-of-the-art GPF products were characterized for their microstructure properties with lab-bench checks for pressure drop and filtration efficiency, then pre-conditioned with an EPA-recommended 1500 mile on-road break-in, and finally were tested on an AWD vehicle chassis-dyno emissions test cell at both 25°C and -7°C ambient conditions. A modern, T3B70, GTDI light-duty truck served as the test vehicle platform for this study. This report will show that advanced uncoated GPFs can repeatedly demonstrate high PM filtration efficiency, positioning them well as one solution to meet the US EPA proposed 0.5 mg/mile PM limit.

Craig, Angus, Warkins, Jason, Wassouf, Bassel, Beall, Douglas, Banker, Vonda, Madaffari Jr, Dominick

Development of an Automatic Pipeline for Data Analysis and Pre-Processing for Data Driven-Based Engine Emission Modeling in a Real Industrial Application

2024-01-2018

4/9/2024

During the development of an Internal Combustion Engine-based powertrain, traditional procedures for control strategies calibration and validation produce huge amount of data, that can be used to develop innovative data-driven applications, such as emission virtual sensing. One of the main criticalities is related to the data quality, that cannot be easily assessed for such a big amount of data. This work focuses on an emission modeling activity, using an enhanced Light Gradient Boosting Regressor and a dedicated data pre-processing pipeline to improve data quality. First thing, a software tool is developed to access a database containing data coming from emissions tests. The tool performs a data cleaning procedure to exclude corrupted data or invalid parts of the test. Moreover, it automatically tunes model hyperparameters, it chooses the best set of features, and it validates the procedure by comparing the estimation and the experimental measurement. The proposed pre-processing pipeline shows an improvement in terms of accuracy, demonstrating the utility of using large training data which cover a wide set of vehicle maneuvers. Thus, custom designed tests are performed for dataset enrichment, allowing the model to predict non-conventional conditions of aftertreatment systems inefficiency. Real case applications of the proposed model are exposed, such as emission estimation in non-measurable conditions, virtual assessment of the impact of new control strategy calibration on emissions, alignment of emission measurements with all other vehicle signals. Finally, a Principal Component Analysis-based algorithm is developed, to assess the epistemic uncertainty of the model and the prediction reliability during inference.

Petrone, Boris, Giovannardi, Emanuele, Brusa, Alessandro, Cavina, Nicolò, Kitsopanidis, Ioannis

Tiny, Fully Functional Water-Strider and Mini-Bug Robots

TBMG-50371

4/1/2024

Two insect-like robots, a mini-bug and a water strider, developed at Washington State University, are the smallest, lightest and fastest fully functional micro-robots. Such miniature robots could someday be used for work in areas such as artificial pollination, search and rescue, environmental monitoring, micro-fabrication or robotic-assisted surgery.

GPF: An Effective Technology to Minimize Two Wheeler (2Wh) Particulate Emission

2024-26-0140

1/16/2024

India is the world’s largest two-wheeler (2Wh) market. With the proportion of its middle class rapidly rising, 2Wh sales and the resulting emissions, are expected to grow exponentially. The decision to leap-frog from BSIV to BSVI emission norms shows India’s commitment to clean up its atmosphere. As of now, the regulation mandates Gaseous Pollutant (CO, HC, NOx) emission limits for all 2Whs and a particulate limit (PM & PN) for 2Whs powered by Direct Injection (DI) engines. Most of the 2Whs manufactured in India are powered by gasoline engines using the Port Fuel Injection (PFI) technology, and hence by definition particulate emission limits do not apply to them. Particulates when inhaled - especially of the ultrafine sizes capable of entering the blood stream - pose a serious health risk. This was the primary motivation to investigate the particulate emission levels of the 2Whs, which as on date, do not come under the purview of BSVI regulation. A study was conducted selecting a motorcycle each from two different vehicle categories – Class 1 and Class 2-1 – as defined under the Indian 2Wh regulation. In the first phase of testing, emissions from both motorcycles in “as is” condition, were measured under WMTC conditions. While the CVS diluted PN emission for the Class 1 motorcycle was found to be 2.2 X 1011 #/km, the same for the Class 2-1 motorcycle was even higher at 7.0 X 1011 #/km. In the second phase, the emission control system for each of the motorcycles was retrofitted with a Gasoline Particulate Filter (GPF) as an “add-on”, downstream to the “as is” catalytic converter system, and emission tests were repeated. Addition of the GPF reduced the particulate emissions by more than 80%. Thus, the study shows that the particulate emissions from the 2Whs are high enough to adversely impact air quality and advanced emission control solutions like the GPF can effectively minimize the 2Wh particulate emissions.

Bhimavarapu, Aditya, Singh, Sunil Kumar, Kataria, Rohit, Rose, Dominik, Boger, Thorsten

The Effect of Different Air Path Based ATS Thermal Management Strategy on a Non- EGR Medium Duty Diesel Engine’s Performance and Emissions

2024-26-0038

1/16/2024

The major objective of this paper is to develop thermal management strategy targeting optimum performance of Selective Catalytic Reduction (SCR) catalyst in a Medium Duty Diesel Engine performing in BS6 emission cycles. In the current scenario, the Emissions Norms are becoming more stringent and with the introduction of Real Drive Emission Test (RDE) and WHTC test comprising of both cold and hot phase, there is a need to develop techniques and strategies which are quick to respond in real time to cope with emission limit especially NOx. SCR seems to be suitable solution in reducing NOx in real time. However, there are limitations to SCR operating conditions, the major being the dosing release conditions which defines the gas temperature at which DEF (Diesel Exhaust Fluid) can be injected as DEF injection at lower gas temperatures than dosing release will lead to Urea deposit formation and will significantly hamper the SCR performance. The second factor for optimum SCR operation is to maintain the catalyst temperature where high NOx conversion efficiency is obtained. Dosing release temperature plays an important role to achieve high NOx conversion efficiency, specifically when the aftertreatment system is at ambient temperature. Therefore, thermal management strategy is employed to ensure quick heating of ATS to achieve the Dosing release temperature in the shortest possible time duration. Thermal management involves air path control where actuators are used to alter the exhaust temperature, and also the injection strategies that favors higher exhaust enthalpy at the cost of BSFC. Thermal Management is active until the ATS will reach the certain temperature threshold beyond which the thermal management will be deactivated as prolong activation of thermal management may result in fuel penalty. From the airpath point of view the focus of this paper is towards the utilization of intake throttling, engine brake and variable exhaust flap. Along with the airpath, the impact of combustion retardation is also covered.

Sharma, Ajeet Kumar, Kreuzig, Gerhard, Gupta, Ayush, Goyal, Dinesh, Garg, Varun

Reproducibility of Physico-Chemical Properties in Brakes Emissions Generated at Different Dynamometric Benches

2023-01-1877

11/5/2023

In recent years, brakes emission tests have become increasingly standardized to meet progressively stricter intra and inter laboratory reproducibility requirements. In particular, following the recent EURO 7 regulation proposal, WLTP-Brake cycle has surged as EU standard braking sequence to determine emission factors of investigated brake systems. Furthermore, the UN GTR (United Nations Global Technical Regulation) on Laboratory Measurement of Brake Emissions for Light-Duty Vehicles collects all the information needed to perform emission tests in laboratory. This includes design specifications for the testing platforms as well as the typology and configuration of measuring instruments. Notably, laboratory emission tests are also increasingly used to collect particulates for chemical characterization, since the compositional information is crucial to: i) provide correct assessment of their toxicological and environmental behavior; and ii) better understand tribological and emission mechanisms. Therefore, this work specifically aims at investigating the topic of the inter laboratory reproducibility of physico-chemical properties in particulates generated by the same friction couple when collected during emission tests carried out on different testing platforms. In particular, the contribution focuses on the comparison of PM10 emissions generated by three different friction couples (i.e., ECE R90 Low Steel, NAO and Inorganic-bound friction materials coupled against grey cast iron brake discs) during sets of WLTP tests performed at two different facilities. More in detail, a wide physico-chemical characterization performed by Scanning Electron Microscopy (SEM), Energy Dispersive X-Ray Spectroscopy (EDXS) and X-Ray Diffraction (XRD) analysis is used to unveil the inter laboratory reproducibility of both the particle size distribution and the chemical composition of corresponding twin particulates collected at the two testing laboratories. The reported results will provide useful insights regarding the variability level to be currently expected in selected physico-chemical properties of non-exhaust emissions from brakes when collected in different testing facilities.

Mancini, Alessandro, Tsyupa, Bozhena, Della Bella, Pietro, Russo, Simone, Martinelli, Elia, Leonardi, Mara, Belotti, Stefano, Hense, Maximilian, Niemann, Hartmut, Bertasi, Federico, Bonfanti, Andrea

Brake Emission Testing Process – Assuring Repeatability and Reproducibility of Emission Measurement Results

2023-01-1876

11/5/2023

Non-exhaust emissions are clearly one of the focal points for the upcoming Euro 7 legislation. The new United Nations Global Technical Regulation (UN GTR) defining the framework for brake emission measurements is about to be officially published. The first amendment to this text is already on the way through the United Nations Economic Commission for Europe (UNECE) hierarchy for decision making. In real life, the final emission factor as the ultimate result of a test is influenced by inaccuracies of numerous parts of the measurement system as well as additional contributing factors like the performance of the particulate filter handling process, which might not be primarily related to equipment specifications. The regulation’s definitions set the basic requirements for testing, whilst establishing a robust and efficient testing process requires a thorough assessment of the influencing factors on the measurement quality, which in turn can be described using e.g., repeatability and reproducibility. This study shows these influences of the system’s inherent sources of imperfection on result quality, based on theoretical relations, simulations, measurement results and experience gathered during productive brake emission testing. Essential process performance indicators are derived to allow suitably low uncertainty of results for homologation and development purposes. Based on this, it might make sense for testing organizations to tighten their internal technical specifications for specific topics beyond current regulation’s requirements to allow efficient testbed operation and deliver superior data quality. Considering lower absolute emission levels in the future, understanding these influencing factors will get even more important.

Weidinger, Christoph, Martikainen, Sampsa, Wanek-Ruediger, Christian, Huber, Michael, Rainer, Andreas

Using the XiL Approach for Brake Emission Investigations for Electrified Vehicles

2023-01-1891

11/5/2023

The following paper aims to bring the topics of connected testing and emission measurements together. It is an introduction of connected bench testing with the aim to characterize brake particle emissions with a special focus on the impact of regenerative braking by simulating the real behavior of a premium BEV SUV. Such an approach combines the advantages of a brake dynamometer including an emission testing setup and a HiL setup to allow a much more precise testing of brake particle emissions under the impact of regen braking compared to the current recommendations of the Global Technical Regulation (GTR) on brake particle emissions. It is shown for the very first time, how interactions between the vehicle motion system work. The study includes one physical front brake corner as well as one physical rear brake corner. The regen functionalities are simulated by a real ESC-ECU which is the core of the HiL test setup. The presented results will deal with the simulation accuracy, the interactions between the powertrain and friction brake as well as the impact on brake emissions.

Gramstat, Sebastian, Gramstat, Elizaveta, Hense, Maximilian, Zessinger, Marco

How to Accomplish a More Sustainable Internal Combustion Engine Using Life Cycle Analysis: A Demo

2023-01-1657

10/31/2023

The Sustainable Development Goals were adopted by all United Nation Member States in 2015 to ensure a sustainable planet and improved living conditions for everyone, everywhere. The light duty vehicle (LDV) fleet has exceeded one billion, with most vehicles being powered by internal combustion engines. Transportation is responsible for 60% of global fossil oil consumption. Air pollution is a large problem in cities often attributed to road transport. Vehicles comprise of over 70 material categories, indicating the complexity of sustainable material management. A hypothesis was established, that a sustainable engine (SE) could significantly reduce the environmental impact of transportation and, be realized by combining available technologies. A life cycle analysis was conducted on a 145 kW 2-litre Miller-cycle gasoline 48V-mild-hybrid engine with EU6d exhaust aftertreatment system (EATS), assessing seven mid-point categories. The environmental impacts were used to establish sustainable lifecycle target levels for carbon dioxide equivalent (CO2eq), carbon monoxide (CO), nitrous oxides (NOx) and total-hydrocarbons (THC). A system solution was designed and manufactured to meet the proposed targets. Recycled materials have been applied and verified to multiple components, realizing a 71% reduction in cradle-to-gate Climate Change (CC) impact for the complete engine. An exhaust aftertreatment system (EATS) was developed and tested via a method using a vehicle emissions test cycle adopted on a dynamic engine bench. Considerations were performed for the possibility to use recycled platinum group materials (PGMs) in the catalytic converter. Air pollutant levels were reduced over 90% for the first 390s of the Worldwide Harmonized Light Vehicles Test Procedure (WLTP). A renewable gasoline was tested achieving a 65% lower fuel life cycle climate change impact. Over the complete engine and fuel life cycle a 61% reduction in climate change impact was achieved. The method and demonstrated technology provide insights into a sustainable system solution for an internal combustion engine. Challenges were identified and discussed in relation to primary data collection, establishing circular supply chains and quantifying targets.

Dudley, Joshua Paul, Laurell, Mats, Thuve, Christoffer, Klövmark, Henrik

Post-Mortem Analysis of DAAAC and Conventionally Aged Aftertreatment Systems

2023-01-1656

10/31/2023

Upcoming regulations from CARB and EPA will require diesel engine manufacturers to validate aftertreatment durability with full useful life aged components. To this end, the Diesel Aftertreatment Accelerated Aging Cycle (DAAAC) protocol was developed to accelerate aftertreatment aging by accounting for hydrothermal aging, sulfur, and oil poisoning deterioration mechanisms. Two aftertreatment systems aged with the DAAAC protocol, one on an engine and the other on a burner system, were directly compared to a reference system that was aged to full useful life using conventional service accumulation. After on-engine emission testing of the fully aged components, DOC and SCR catalyst samples were extracted from the aftertreatment systems to compare the elemental distribution of contaminants between systems. In addition, benchtop reactor testing was conducted to measure differences in catalyst performance. Sulfur was deposited uniformly on the aftertreatment components while the oil derived phosphorous deposited more heavily at the system inlet. Consistent with on-engine emission testing results, the reference system SCR had worse overall NOX conversion performance, though the performance was still within the specification of commercially available aftertreatment systems. High levels of oil-derived phosphorous deposited on the DAAAC-Engine SCR inlet greatly inhibited NOX conversion but improved as the phosphorous levels decreased axially along the SCR, suggesting more volatile oil was introduced into the DAAAC-Engine system. Improvements to the DAAAC protocol to better represent real world aging are discussed.

Seuser, Grant, Eakle, Scott, Rahman, Mohammed Mustafizur, Sharp, Christopher, Zavala, Bryan

Engine Efficiency and Emissions Improvement in a Parallel-Series PHEV

2023-01-5072

10/12/2023

While there is a continued push toward mass adoption of electric vehicles globally, internal combustion engines seem posed to continue to play a key role in the mobility industry even as electrified powertrains continue to increase in market share. For internal combustion engines to continue to propel people and goods, engine technologies need to continuously improve in both efficiency and emissions. This paper will explore six technologies to increase the efficiency and reduce the emissions output of an engine in a plug-in hybrid-electric vehicle (PHEV). The technologies employed on this prototype vehicle include deceleration fuel cutoff, start–stop, increasing the mean engine operating temperature, preheating the engine oil, implementing an electrically heated catalyst, and air–fuel ratio control. Each of these technologies have been well studied and have demonstrated robustness through decades of deployments on road. However, pairing these technologies with a PHEV architecture will enable the benefits of these technologies to be fully exploited. It will be demonstrated that the combined application of these six technologies increased the experimental vehicles miles per gallon gasoline equivalent by 22% and reduced greenhouse gas emissions by 32% over a real-world driving emissions baseline. This paper will explore the background and anticipated impacts that these technologies should have, as well as demonstrate their implementation on the experimental vehicle. Emphasis will be placed on the way each of these technologies were tested and the environment that they were tested in. The testing environments include an engine dynamometer, a chassis dynamometer, and real-world driving emission tests. In all these settings, the efficiency and emissions were measured. The final test involves a real-world driving emissions test. The vehicle in question is an experimental PHEV developed by students at The Ohio State University. Results and conclusions are drawn from the data collected for how each of these technologies impacted engine operation in the PHEV.

Jankord, Gregory, Modak, Aditya, Dalke, Phillip, Midlam-Mohler, Shawn

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