With the rapid development of smart transport and green emission concepts, accurate monitoring and management of vehicle emissions have become the key to achieving low-carbon transport. This study focuses on NOx emissions from transport trucks, which have a significant impact on the environment, and establishes a predictive model for NOx emissions based on the random forest model using actual operational data collected by the remote monitoring platform.The results show that the NOx prediction using the random forest model has excellent performance, with an average R2 of 0.928 and an average MAE of 43.3, demonstrating high accuracy. According to China's National Pollutant Emission Standard, NOx emissions greater than 500 ppm are defined as high emissions. Based on this standard, this paper introduces logistic regression, k-nearest neighbor, support vector machine and random forest model to predict the accuracy of high-emission classification, and the random forest model has the best

Lin, Yingxin, Li, Tiezhu

Study on the Impact of Arrangement of Urea Injector and Mixer in Diesel Engine Selective Catalytic Reduction System on Ammonia Uniformity

02-18-02-0007

02/12/2025

With the continuous upgrading of emission regulations for internal combustion engines, the nitrogen oxide treatment capacity of selective catalytic reduction (SCR) aftertreatment needs to be continuously improved. In this study, based on a prototype of SCR aftertreatment, the impact of the arrangement of key components in the SCR system (urea injector, mixer, and catalyst unit) on ammonia uniformity was investigated. First, parameterized designs of the urea injector, mixer, and SCR unit were conducted. Then, using computational fluid dynamics (CFD), numerical simulations of the established aftertreatment system models with different parameter factors were performed under a high-exhaust temperature and a low-exhaust temperature conditions to study the impact of each individual parameter on ammonia uniformity. Finally, an optimized solution was designed based on the observed patterns, and the optimized samples were tested on an engine performance and emission test bench to compare their

Jie, Wang, Jin, Jianjiao, Wu, Yifan

A Novel Approach to develop the Exhaust Backpressure Measurement System for Automotive Application

2025-28-0168

02/07/2025

Backpressure is one of key acoustic performance evaluation criteria of exhaust muffler (or Silencer) /EATS (Exhaust after treatment system) as well as for the exhaust system. Exhaust back pressure is an important parameter for fuel efficiency of a vehicle. Typically, the engine manufacturer specifies an upper limit for this. Usually, exhaust back pressure is measured during the driving condition of the vehicle at maximum power condition of the engine either on road or on chassis dynamometer. Both these methods, need a lot of preparatory works, test setup arrangement, 3 or more manpower and special skills. In this research, authors are tried to develop a new backpressure measurement set up for automotive vehicle application, which is simple and innovative, to fulfill the backpressure test requirement. In this design, mainly following devices are used namely Pitot tube, Compressed air, Manometer (or pressure gauge), Thermocouple, Fluke thermometer, along with standalone exhaust layout

Mandal, Goutam, Biswas, Sanjoy

Prediction of Diesel Engine NO _x Transient Emissions Based on a Combined Model with Convolutional Neural Network–Efficient Channel Attention–Bidirectional Gated Recurrent Unit

03-18-02-0012

02/06/2025

Widely used as power equipment, diesel engines emit NO x , which significantly threatens the well-being of both the ecosystem and individuals. The SCR system, which is employed to reduce NO x emissions from diesel engines, relies on precise control of the NO x emission levels. Addressing the challenge that traditional NO x emission prediction methods struggle to accurately forecast the emissions under transient operating conditions, this article introduces a deep learning model that integrates CNN, ECA, and BIGRU. The model’s necessary experimental data were collected during the hot phase of the WHTC, and input parameters were screened through correlation analysis. The model employs a CNN for feature extraction, integrates an ECA module to refine key feature processing, and utilizes BIGRU to capture temporal dynamics and dependencies, yielding predictive outcomes. Additionally, the model employs the Adam optimizer and combines it with BWO to adjust hyperparameters, thereby elevating

Peng, Yunlong, Wang, Guiyong, Wang, Yuhua, Wang, Feiyang, Wang, Zhiyuan, He, Shuchao

Enhanced High-Temperature Performance of NH ₃ -SCR Catalysts for Lean-Burn Engines

2025-01-7043

01/31/2025

NOx after-treatment has greatly limited the development of lean-burn technology for gasoline engines. NH3-Selective Catalytic Reduction (SCR) technology has been successfully applied to NOx conversion in diesel engines. For gasoline engines, SCR catalyst is required to maintain high activity over a higher temperature window. In this study, we utilized a turbocharged and intercooled 2.0 L petrol engine to investigate the NOx conversion of two zeolite-based SCR catalysts, Cu-SSZ-13 and Fe/Cu-SSZ-13, at exhaust flows ranging from 80 to 300 kg/h and exhaust temperatures between 550 to 600°C. The catalysts were characterized using SEM, ICP, XRD, H2-TPR, NH3-TPD, and other methods. The selected Fe/Cu-SSZ-13 catalyst showed higher NOx conversion (>80%) in the temperature range of 550~600oC and 80~300 kg/h exhaust gas flow. NOx output could be controlled below 10ppm. The characterization results showed that although the specific surface area and acidic sites decreased after the aging treatment

Pan, Shiyi, Wang, Ruwen, Zhang, Nan, Xu, Zhiqin, Hu, Jiangtao, Liao, Xiuke, Duan, Pingping, Chen, Ruilian

First Principle Study of Catalyst’s Influence on Self-Inhibition Effect and By-Products Formation of Lean NOx Trap

2025-01-7042

01/31/2025

Lean NOx trap is a dedicated DeNOx catalyst for lean hybrid gasoline engines. Noble metals (usually platinum group metals) play the role of catalytic sites for NOx oxidation and reduction, which have significant impact of the performance of LNT. This work focuses on the influence of noble metal catalysts on self-inhibition effect from the view of competitive adsorption between NO and CO, and investigates the influence of CO self-inhibition effect on the main by-product of LNT: N2O formation. Adsorption configurations for NO, CO and N2O on noble metal clusters supported by γ-Al2O3(100) are confirmed. For detailed investigation, electron structures are analyzed by investigating Bader charge, DOS (density of state), charge density differences and COHP (crystal orbital Hamilton population) of selected configurations.The results show that CO self-inhibition effect is caused by competitive adsorption between CO and NO. The essence of competitive adsorption between CO and NO is that

Liu, Mingli, Liu, Yaodong, Qu, Hanshi, Duan, Jiaquan, Zhang, Qiqi, Qian, Dingchao, Wang, Zhenxi, He, Zhentao

Research on Noise Optimization of Exhaust System for Hydrogen Fuel Cell Vehicles

2025-01-7003

01/31/2025

This paper presents a strategy to reduce exhaust noise in fuel cell vehicles. It focuses on optimizing the exhaust system. The innovation is an integrated muffler device. It combines a vapor separator and an absorptive-reactive muffler. The vapor separator removes moisture from exhaust gases. This prevents damage to sound-absorbing materials. It keeps mufflers functional for longer. Fuel cell vehicles produce noise across a wide frequency range. This makes noise reduction challenging. The absorptive-reactive muffler improves noise attenuation. It works across the full frequency spectrum. The combination of the separator and muffler enhances noise reduction. Simulations show high transmission loss. They also confirm acceptable back pressure. Real-vehicle testing supports these results. The optimized system reduces idle noise by 22.1 dB(A). This is a 32.4% reduction. Blowdown noise is reduced by 46.3 dB(A), or 40.1%. Full-throttle noise drops by over 20 dB(A), a 17.2% decrease. The

Zhou, Jiawang, Jiang, Xiaokun, Qiu, Yongjin, Chen, Jiyuan, Feng, Pengfei, Xie, Qiguang, Xie, Xiaoping, Tan, Ligang

Research on the Characteristics of an Integrated Thermoelectric Generation, Catalytic Conversion, and Noise Suppression System

2025-01-7062

01/31/2025

In the context of global energy shortages and increasing environmental pollution, improving energy efficiency in automobiles has become a key area of research. Traditional internal combustion engines exhibit low energy conversion efficiency, with a significant portion of fuel energy wasted as exhaust heat. To address this issue, this paper proposes an integrated thermoelectric generation, catalytic conversion, and noise suppression system (ITGCMS) aimed at recovering waste heat from vehicle exhaust, while optimizing emissions and noise reduction through the combination of a catalytic converter and a muffler. A three-dimensional model was established using COMSOL software to thoroughly analyze the system's thermoelectric generation, catalytic conversion, and acoustic performance. The study found that Model B demonstrated the best thermoelectric performance, with an average surface temperature of 300.2°C and a more uniform temperature distribution across the thermoelectric modules

Wu, Ji-Xin, Su, Chu-Qi, Wang, Yi-Ping, Yuan, Xiao-Hong, Liu, Xun

Thermal Energy Balance of an Otto Cycle Engine Fueled with Ethanol and Gasoline

2024-36-0003

12/20/2024

Otto Cycle can operate with both gasoline and ethanol; however, these fuels have different properties that will result in different performance parameters. This work aims to compare the thermal energy balance of an internal combustion engine fueled with gasoline and ethanol. The experimental tests were carried out on a dynamometer bench varying engine speed between 1500 and 6000 rpm and at full load condition. The results showed that the engine’s maximum thermal efficiency ranged from 30.51% with gasoline to 31.72% with ethanol. The percentage of energy dissipated to the cooling system varied from 16.93% with gasoline from 16.12% with ethanol. The percentage of energy dissipated to the exhaust system ranged from 32.82% with gasoline from 34.64% with ethanol. The percentage of energy wasted due to incomplete fuel combustion varied from 3.50% with gasoline from 10.00% with ethanol. The percentage of energy dissipated to the lubrication system ranged from 3.95% with gasoline from 3.76

Santana, Claudio Marcio, Santana, Linicker Lopes Bruno, Almeida, Helder Giostri Alves

Low-Cost Improvements of an Old Flow Bench and a Discussion of Replacing Orifice Plate by MAF in its Flow Measurement

2024-36-0070

12/20/2024

Recognizing the significant challenges inherent in the analysis of periodic gas flow through reciprocating engines, one can easily appreciate the value of studying the steady flow through cylinder heads, manifolds, and exhaust systems. In these studies, flow benches are the cornerstone of the experimental apparatus needed to validate theoretical results or to perform purely experimental analysis. The Metal-Mechanics Department of IFSC owns a SuperFlow model SF-110 flow bench that has suffered some in house maintenance and received electronic sensors to allow computerized data acquisition. As the essential original sensors in this flow bench were liquid column manometer (for pressure difference across the test subject) and micromanometer (for pressure difference across the orifice plate used to measure the flow), the essential new sensors are electronic differential pressure sensors (installed in parallel with the original ones). In recent decades, however, the use of a mass air flow

Vandresen, Marcelo, dos Santos, Luciano Amaury

Vibration Measurement on Diesel Engine Components under Adverse Conditions in Brazilian Application

2024-36-0021

12/20/2024

The objective of this study is to investigate the root cause of cracks detected in the Turbocharger bracket belonging to the engine Mercedes-Benz OM471 (Power: 390kW, Torque: 2600Nm) from Vehicle Truck Mercedes-Benz Actros 2651LS 6x4 Euro V. The investigation started with the instrumentation of every related component (besides the bracket itself, the charge air pipe, the exhaust pipe and also the crankcase for reference) in order to perform a vibration measurement. The necessary equipment to execute this procedure, included accelerometers, temperature sensors, strain gages and an inductive engine speed sensor. All data had to be acquired directly from real application conditions in vehicle, maximum load of 74 ton in a previously defined mountain road track, due to the impossibility to generate similar results in comparison to the ones detected on road through bench tests (or any other in-door experiment). The bracket position is located on the right side of a diesel combustion engine

Feijó, Igor Sommerfeld, Gonçalves, Carlos Aurélio Bustamante

Dynamic Modeling of Torque & Emissions: Digital Twin to Simulate Combustion Process and Exhaust Emissions for Diagnostics & Prognostics Applications

2024-28-0172

12/05/2024

As a journey to green initiatives, one of the focus areas for automotive industry is reducing environmental impact especially in case of internal combustion engines. Latest digital twin technology enable modelling complicated, fast and unsteady phenomena including the changes of emission gases concentration and output torque observed during diesel emission and combustion process. This paper presents research on the emission and combustion characteristics of a heavy vehicle diesel engine, elaborating an engineered architecture for prognostics/diagnostics, state monitoring, and performance trending of heavy-duty vehicle engine (HDVE) and after treatment system (ATS). The proposed architecture leverages advanced modeling methodologies to ensure precise predictions and diagnostics, using data-driven techniques, the architecture accurately model’s engine and exhaust system behaviors under various operating conditions. For exhaust system, architecture demonstrates encouraging predictive

Singh, Prabhsharn, Thakare, Ujval, Hivarkar, Umesh

Comprehend Dynamic Behaviour of Vehicle Body for Refined NVH Performance

2024-28-0265

12/05/2024

Modal performance of a vehicle body often influences tactile vibrations felt by passengers as well as their acoustic comfort inside the cabin at low frequencies. This paper focuses on a premium hatchback’s development program where a design-intent initial batch of proto-cars were found to meet their targeted NVH performance. However, tactile vibrations in pre-production pilot batch vehicles were found to be of higher intensity. As a resolution, a method of cascading full vehicle level performance to its Body-In-White (BIW) component level was used to understand dynamic behavior of the vehicle and subsequently, to improve structural weakness of the body to achieve the targeted NVH performance. The cascaded modal performance indicated that global bending stiffness of the pre-production bodies was on the lower side w.r.t. that of the design intent body. To identify the root cause, design sensitivity of number and footprint of weld spots, roof bows’ and headers’ attachment stiffness to BIW

Titave, Uttam Vasant, Zalaki, Nitin, Naidu, Sudhakara

Novel UWS Injection Technique for SCR Performance Improvement

2024-28-0133

12/05/2024

The present study aims to meet the Euro-VII compliance applicable for internal combustion engines (diesel and hydrogen) by improving the performance of selective catalytic reduction (SCR) system using a novel urea water solution (UWS) mist injection technique. In SCR system, the interaction of exhaust gas and UWS resulted into ammonia (NH3) species, which is mixed with harmful NOx emission and converted into harmless by-products. Despite the proven technology, there are several challenges presented in the existing system which restricts the ideal performance of SCR system especially during cold starting condition: (i) incomplete droplet evaporation (ii) solid deposit formation (iii) non uniformity of NH3 distribution at the catalyst entrance. The past studies shows that the droplet size plays a major role in this context. Further, it is noted that the smaller size droplets are desirable to overcome the impediments and enhance the efficiency of SCR application. Therefore, it is decided

Venkatachalam, Palaniappan, Shiva, Shashidhar, Govindarajan, Vaishali, Soni, Prerna, Patidar, Sachin

Machine Learning Approach to Control Thermal Strategies and Mitigate Sensor Failure Penalty on Emissions

2024-28-0170

12/05/2024

As vehicle emission standards are becoming stringent worldwide because of the looming climate crisis, it is important to control the pollutants that vehicles emit. To achieve the stringent emission target, it has become a priority to enhance the capability of Emission Control System (ECS) which consist of Diesel Oxidation Catalyst (DOC), Diesel Particulate Filter (DPF) and Selective Catalytic Reduction (SCR) sub-systems. One of the bottlenecks is the limited operating temperature range of the after-treatment system. In modern emission control systems, the temperature characteristics should always be optimized to have the best efficiency involving chemical conversions. To achieve this optimal operating temperature, different thermal control strategies are followed in the Engine and emission control unit. Temperature sensor values are one of the primary inputs for thermal management strategies. In the event of temperature sensor malfunction, the ECS performance is affected due to

Kumar, Amit, V H, Yashwanth, Kumar, Raman, Hegde, Karthik, Manojdharan, Arjungopal

Development of an Automated Testbench for Functional Testing of Dosing Unit

2024-28-0202

12/05/2024

Increasingly stringent emission regulations continue to be legislated around the world to significantly minimize pollutants released to the air by internal combustion engines. After Treatment Systems (ATS) meant for reducing oxides of nitrogen (NOx) in the exhaust into non-harmful species have evolved at a rapid pace over the past two decades. Stringent emissions requirements have driven complex ATS architecture through sensors to measure delta-pressure, NOx, and temperatures. Accurate and precise performance of individual components as well as the integrated ATS is required to ensure regulatory compliance and efficient performance. Both of which require substantial amounts of performance and validation testing. Manufacturers have been developing the ability to accurately and efficiently test the ATS components. To meet the norms for tail pipe or stack emissions of NOx in ‘as new’ condition and during the entire ‘emissions useful life (EUL)’ of the ATS, all components of an ATS must

Raut, Pratiksha C, Ottikkutti, Pradheepram, Phadke, Abhijit Narahari, Magar, Vijay A.

Catalyzed Gasoline Particulate Filter Performance from Fresh to Full Useful Life

2024-01-4311

11/05/2024

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

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

Physics Based On-Board Exhaust-Temperature Prediction Model for Highly Efficient and Low-Emission Powertrain

2024-01-4273

11/05/2024

Modern automotive powertrains are operated using many control devices under a wide range of environmental conditions. The exhaust temperature must be controlled within a specific range to ensure low exhaust-gas emissions and engine-component protection. In this regard, physics-based exhaust-temperature prediction models are advantageous compared with the conventional exhaust-temperature map-based model developed using engine dyno testing results. This is because physics-based models can predict exhaust-temperature behavior in conditions not measured for calibration. However, increasing the computational load to illustrate all physical phenomena in the engine air path, including combustion in the cylinder, may not fully leverage the advantages of physical models for the performance of electric control units (ECUs). This study proposes an onboard physics-based exhaust-temperature prediction model for a mass-produced engine to protect the engine exhaust system and reduce exhaust emissions

Yamaguchi, Seiya, Tomita, Masayuki, Urakawa, Shinji, Ookubo, Seiichi

Experimental and Numerical Investigations on the Effect of Urea Pulse Injection Strategies to Reduce NOx Emission in Urea-SCR Catalysts

2024-01-4304

11/05/2024

A major challenge for auto industries is reducing NOx and other exhaust gas emissions to meet stringent Euro 7 emission regulations. A urea Selective Catalyst Reduction (SCR) after-treatment system (ATS) commonly uses upstream urea water injection to reduce NOx from the engine exhaust gas. The NOx emission conversion rate in ATSs is high for high exhaust gas temperatures but substantially low for temperatures below 200°C. This study aims to improve the NOx conversion rate using urea pulse injection in a mass-production 2.2 L diesel engine equipped with an SCR ATS operated under low exhaust gas temperature. The engine experimental results show that, under 200°C exhaust temperature and 3.73x104 h-1 gross hourly space velocity (SV), the NOx conversion rate can be improved by 5% using 5-sec ON and 12-sec OFF (denoted as 5/12 s) urea pulse supply compared to the constant supply under time-averaged 1.0 urea equivalence ratio. It is experimentally observed that the urea pulse supply’s

Yoshida, Fuka, Takahashi, Hideaki, Kotani, Yuya, Zu, Qiuyue, Sok, Ratnak, Kusaka, Jin

The Effect Mechanism of Grain Size with Nanoscale and Microscale on Physical and Chemical Properties of Cu/SSZ-13 SCR Catalyst

2024-01-4305

11/05/2024

Selective catalytic reduction (SCR) technology is currently one of the most effective methods to reduce NOx emissions for engine. NH3-SCR technology is also considered to be the most promising hydrogen engine after-treatment device. This paper used Cu-SSZ-13, which is widely commercially available, as the research object, and explored the relationship between micron and nanoscale grain sizes through experimental methods such as BET, XRD, NH3-TPD, UV-vis-DRS and activity testing, the influence mechanism of micron-scale and nano-scale grain size on the morphology and properties of Cu/SSZ-13 catalyst was explored. The results show that the fresh nanoscale 900F sample has higher low-temperature NOx conversion efficiency, while the micron-scale 1800F sample has poor low-temperature activity and better high-temperature activity. This is closely related to its morphological characteristics, adsorption and desorption characteristics and dual-site properties. The specific surface area and total

Chen, Yajuan, Lou, Diming, Zhang, Yunhua, Tan, Piqiang, Fang, Liang, Hu, Zhiyuan

Accurate Urea Consumption Prediction in SCR System Using CFD Simulation

2024-28-0100

09/19/2024

The selective catalytic reduction (SCR) is a technique, which is using in diesel engine to reduce harmful nitrogen oxide (NOx) emissions. SCR technique involves the injection of urea-water-solution (Water-urea solution) into the hot exhaust stream. The water first evaporates and then urea undergoes thermal decomposition. The thermal decomposition of urea produces ammonia, which reacts with the nitrogen oxides inside a SCR catalyst layers and nitrogen and water vapor are the final product. The production of ammonia from urea strongly influenced by the droplet size, residence time of the droplets inside decomposition chamber and exhaust gas temperature. During the combustion process of Diesel engines, Nitrogen oxide (NOx) is produced as a pollutant which is harmful for environment. Acceptance level of (NOx) is made more stringent in BS-VI and subsequent standards to regulate (NOx) levels. In SCR system NH3 reacts with (NOx) and converts N2 and H2O. Ammonia (NH3) concentration and

Chaudhary, Alok Subhash, Ghodake, Preetam, Biswas, Kundan

Multiphase Flow Simulation of Blow-by and Fuel-in-Oil Dilution via the Piston Ring Pack Using the Level-Set Method

04-18-01-0003

09/09/2024

Modern diesel engines temporarily use a very late post-injection in the combustion cycle to either generate heat for a diesel particulate filter regeneration or purge a lean NOx trap. In some configurations, unburned fuel is left at the cylinder walls and is transported via the piston rings toward the lower crankcase region, where fuel may dilute the oil. Reduced oil lubrication shortens the oil service intervals and increases friction. Beside diesel fuel, this problem may also occur for other types of liquid fuels such as alcohols and e-fuels. The exact transport mechanism of the unburned fuel via the piston ring pack grooves and cylinder wall is hard to measure experimentally, motivating numerical flow simulation in early design stages for an in-depth understanding of the involved processes. A new CFD simulation methodology has been developed to investigate the transient, compressible, multiphase flow around the piston ring pack, through the gap between piston and liner, and its

Antony, Patrick, Hosters, Norbert, Behr, Marek, Hopf, Anselm, Krämer, Frank, Weber, Carsten, Turner, Paul

An Investigation on Exhaust Pulse Characteristics of Asymmetric Twin-Scroll Turbocharged Heavy-Duty Diesel Engine

03-17-06-0048

07/24/2024

The shape and energy distribution characteristics of exhaust pulse of an asymmetric twin-scroll turbocharged engine have a significant impact on the matching between asymmetric twin-scroll turbines and engines, as well as the matching between asymmetric twin scrolls and turbine wheels. In this article, the exhaust pulse characteristics of an asymmetric twin-scroll turbocharged engine was studied. Experiments were conducted on a turbine test rig and an engine performance stand to determine the operation rules of exhaust pulse strength, turbine flow parameters, turbine isentropic energy, and turbine efficiency. The results showed that the exhaust pulse strength at the inlets of both the small and large scrolls continuously decreased with the increase of engine speed. And the flow parameters at the inlets of the small and large scrolls exhibited a “ring” or “butterfly” shape with the change of expansion ratio depending on the pressure deviation of the extreme points at the troughs on both

Wu, Liangqin, Jin, Jianjiao, Wang, Jie, Zhang, Chenyun

Unique Approach of Modern Automotive Exhaust System Mountings Design for NVH Improvement

02-17-03-0015

07/22/2024

Minimizing vibration transmitted from the exhaust system to the vehicle’s passenger compartment is the primary goal of this article. With the introduction of regulatory norms on NVH behavior and emissions targets, it has become necessary to address these issues scientifically. Stringent emissions regulations increased the complexity of the exhaust system resulting in increased size and weight. Exhaust system vibration attenuation is essential not only from the vehicle NVH aspects but also for the optimized functionality of the subsystems installed on it. Based on earlier studies, this work adopts a more thorough strategy to reduce vehicle vibration caused by the exhaust system by adjusting it to actual operating conditions. To achieve this, a complete vehicle model of 22 DOF is considered, which consists of a powertrain, exhaust system, chassis frame, and suspension system. A method for evaluating static and dynamic vibration response is proposed. Through the use of the vehicle’s rigid

Sarna, Amit Kumar, Singh, Jitender, Kumar, Navin, Sharma, Vikas

Impact of AdBlue Composition and Water Purity on Particle Number Increase

2024-01-3012

07/02/2024

Previous studies have shown that dosing AdBlue into the exhaust system of diesel engines to reduce nitrogen oxides can lead to an increase in the number of particles (PN). In addition to the influencing factors of exhaust gas temperature, exhaust gas mass flow and dosing quantity, the dosed medium itself (AdBlue) is not considered as a possible influence due to its regulation in ISO-standard 22241. However, as the standard specifies limit value ranges for the individual regulated properties and components for newly sold AdBlue, in reality there is still some margin in the composition. This paper investigates the particle number increase due to AdBlue dosing using several CPCs. The increase in PN is determined by measuring the number of particles after DPF and thus directly before dosing as well as tailpipe. Several AdBlue products from different sources and countries are measured and their composition is also analyzed with regard to the limit values regulated in the standard. This

Herold, Tim, Noone, Patrick, Beidl, Christian, Boldt, Thomas, Hochholzner, Michael, Kontin, Sinisa

Future Emissions Following 800,000 Mile Aging Using CDA and a Low Power Electric Heater

2024-01-3011

07/02/2024

Engine and aftertreatment solutions have been identified to meet the upcoming ultra-low NOx regulations on heavy duty vehicles in the United States. These standards will require changes to current conventional aftertreatment systems for dealing with low exhaust temperature scenarios while increasing the useful life of the engine and aftertreatment system. Previous studies have shown feasibility of meeting the US EPA and California Air Resource Board (CARB) requirements. This work includes a 15L diesel engine equipped with cylinder deactivation (CDA) and an aftertreatment system that was fully DAAAC aged to 800,000 miles. The aftertreatment system includes an e-heater (electric heater), light-off Selective Catalytic Reduction (LO-SCR) followed by a primary aftertreatment system containing a DPF and SCR. The e-heater was capable of providing up to 10 kW, however for the purpose of this project, lower power settings of 2.5 kW and 5 kW were studied in combination with CDA for lowest

Kramer, Jan, Rice, Michael, Zavala, Bryan, Sharp, Christopher, McCarthy, James, Karrer, Ben

Reduction of Flow-Induced Noise in Refrigeration Cycles

2024-01-2972

07/02/2024

In electrified vehicles, auxiliary units can be a dominant source of noise, one of which is the refrigerant scroll compressor. Compared to vehicles with combustion engines, e-vehicles require larger refrigerant compressors, as in addition to the interior, also the battery and the electric motors have to be cooled. Currently, scroll compressors are widely used in the automotive industry, which generate one pressure pulse per revolution due to their discontinuous compression principle. This results in speed-dependent pressure fluctuations as well as higher-harmonic pulsations that arise from reflections. These fluctuations spread through the refrigeration cycle and cause the vibration excitation of refrigerant lines and heat exchangers. The sound transmission path in the air conditioning heat exchanger integrated in the dashboard is particularly critical. Various silencer configurations can be used to dampen these pulsations. This paper compares the acoustic and thermodynamic performance

Saur, Lukas, Heidegger, Patrick, Naeger, Christoph, Becker, Stefan

Effect of Dithering on Post-Catalyst Exhaust Gas Composition and on Short Time Regeneration of Deactivated PdO/Al ₂ O ₃ Catalysts under Real Engine Conditions

2024-37-0002

06/12/2024

Fossil fuels such as natural gas used in engines still play an important role worldwide which however is also exacerbating climate change as a result of carbon dioxide emissions. Although natural gas engines show an overall low pollutant emissions level, methane slip due to incomplete combustion occurs, causing methane emissions with a more than 20 times higher global warming potential than CO2. Additionally, further tightening of emissions legislation is to be expected bringing methane emissions even more into focus making exhaust gas aftertreatment issues remain relevant. For lean gas applications, (Pd)-based catalysts turned out to convert CH4 most efficiently usually being supported by metal oxides such as aluminium oxide (Al2O3). Water (H2O) contained in the exhaust gas causes strong inhibition on Pd catalysts. In real exhaust gases, not only water vapour but also pollutants and sulphur-containing compounds such as hydrogen sulphide (H2S) or sulphur oxides (SOx) are poisoning the

Tomin, Sebastian, Wagner, Uwe, Koch, Thomas

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