Browse Topic: Fuel economy

Items (7,810)
This report examines the advancement and utilization of cylinder deactivation technology that enhances fuel efficiency in conventional engines without hardware modifications. It operates by halting fuel supply to some of the cylinders in multi-cylinder engines and increasing the output power of the remaining active cylinders to maintain an idle state. By implementing this technology in the mass-produced 90° V-twin engine, the U502, and deactivating one of its two cylinders, fuel consumption during idling is reduced by over 30%. The focus of this study is on the technology developed to minimize engine speed fluctuations during the transition to cylinder deactivation and reactivation for the engine. By making various modifications to the fuel injection control sequence and optimizing the throttle opening of each cylinder in idle and driving conditions, engine speed fluctuations were minimized. This allows users to reduce fuel consumption while maintaining the engine’s original
YANAGIDA, Shoji
Hybrid powertrain for motorcycles has not been widely adopted to date but has recently shown significant increased interest and it is believed to have great potential for fuel economy containment in real driving conditions. Moreover, this technology is suitable for the expected new legislations, reduced emissions and enables riding in Zero Emissions Zones, so towards a more carbon neutral society while still guaranteeing “motorcycle passion” for the product [1, 2]. Several simulation tools and methods are available for the concept phase of the hybrid system design, allowing definition of the hybrid components and the basic hybrid strategies, but they are not able to properly represent the real on-road behaviour of the hybrid vehicle and its specific control system, making the fine tuning and validation work very difficult. Motorcycle riders are used to expect instant significant torque delivery on their demand, that is not properly represented in legislative cycles (e.g. WMTC); rider
Antoniutti, ChristianSweet, DavidHounsham, Sandra
In recent years, the importance of achieving carbon neutrality has been highlighted in response to the escalating severity of climate change. In the leading automobile market, the share of electric vehicles is gradually expanding, especially in passenger car sector. However, it is not same in commercial vehicle sector. In the off-road machinery market, as with electrification in commercial vehicles, the factors such as the need to install charging infrastructure and the requirement for large batteries to expand operating duration are significant challenge to full electrification. As one of the realistic solutions toward carbon neutrality for off-road machines, methods to utilize both internal combustion engines (ICE) and their applied products are being reconsidered. Under the circumstances, we have developed a mild-hybrid (MH) system for small off-road machinery. This system adopts a 48V power supply in order to minimize size of the system offers as a “Drop-in” package solution. This
Koyama, KazuakiKimura, RyotaNagamori, YukoHorita, TatsuhikoNosaka, Kento
This study offers an overview of the impact of lean burn technology in two-wheeler vehicles, specifically concentrating on enhancing the fuel economy and addressing the challenges associated with its adoption. Lean burn systems, characterized by a fuel-air mixture with a higher air content than stoichiometric ratio. The study focuses on technology which meets stringent emission standards while enabling the optimization of fuel efficiency. The lean burn system employs strategies to optimize air-fuel ratio using electronic fuel injection, ignition timing control, and advanced engine control algorithms like - updated torque modulation control algorithm for drivability, lambda control algorithm for rich and lean switch and NOx modelling algorithm for LNT catalyst efficiency tracking. The challenges related to lean burn systems, includes issues related to combustion stability, nitrogen oxide (NOx) emissions, and their impact on drivability, is summarized in the study. Mitigation strategies
Somasundaram, KarthikeyanSivaji, PurushothamanJohn Derin, CVishal, KarwaManoj Kumar, SMaynal, Rajesh
Efforts to enhance fuel efficiency in small gasoline engines, vital for reducing CO2 emissions, are concentrated on minimizing piston friction losses. Achieving this balance while addressing concerns such as piston seizure prevention and minimizing oil consumption presents challenges, particularly in small gasoline engines operating at higher speeds where the risk of piston seizure is significant. Hence, there is a critical need for accurate methods to measure piston friction. This study introduces the development of a measurement apparatus employing the floating liner method, initially devised by Takiguchi [1] and further adapted by Yamasaka for a mono-cylinder air-cooled gasoline engine [2, 3]. Yamasaka’s research successfully investigated the correlation between the apparatus’s natural frequency and the maximum engine speed measurable, achieving piston friction measurement up to 5000 rpm. Expanding on this achievement, this research aims to broaden the application of the floating
Honda, RikuIto, AkemiSaika, SantaYamase, RyoutaHasegawa, TatsuhikoSakioka, TakeruSuda, NaoyukiNinomiya, Yoshinari
Fuel cell vehicles (FCVs) offer a promising solution for achieving environmentally friendly transportation and improving fuel economy. The energy management strategy (EMS), as a critical technology for FCVs, faces significant challenges of achieving a balanced coordination among the fuel economy, power battery life, and durability of fuel cell across diverse environments. To address these challenges, a learning-based EMS for fuel cell city buses considering power source degradation is proposed. First, a fuel cell degradation model and a power battery aging model from the literature are presented. Then, based on the deep Q-network (DQN), four factors are incorporated into the reward function, including comprehensive hydrogen consumption, fuel cell performance degradation, power battery life degradation, and battery state of charge deviation. The simulation results show that compared to the dynamic programming–based EMS (DP-EMS), the proposed EMS improves the fuel cell durability while
Song, DafengYan, JinxingZeng, XiaohuaZhang, Yunhe
India, with its low per capita income vast population and growing middle class, represents a significant market for low-cost, fuel-efficient automobiles. As the largest two-wheeler market globally, a transition to four-wheelers is underway, further driving the demand for affordable vehicles. This necessitates the design and development of low-priced vehicles equipped with efficient and economical powertrains. Globally, stringent regulations like Corporate Average Fuel Economy (CAFE), Worldwide Harmonized Light Vehicles Test Cycles (WLTC), and Real Driving Emissions (RDE) are pushing manufacturers to develop fuel-efficient vehicles. India has also adopted similar regulations, including CAFE2 and Bharat Stage 6-Phase 2 (BS6-2), to improve fuel economy and reduce emissions. These regulations, coupled with the growing demand for affordable vehicles, have spurred innovation in engine technology. In response to these challenges, Maruti Suzuki India Limited (MSIL) has consistently focused on
Singh, AmandeepSingh, JaspreetJalan, AnkitKumar, Narinder
The Rotating Liner Engine (RLE) is a design concept where the cylinder liner of a heavy-duty Diesel engine rotates at about 2-4 m/s surface speed to eliminate the piston ring and skirt boundary friction near the top and bottom dead center. Two single cylinder engines are prepared using the Cummins 4BT 3.9 platform, one is RLE, the other is baseline (BSL), i.e. conventional. In 2022, we published the test results of the RLE under load, but we lacked detail test data for the baseline. In this new set of experiments, we compare the RLE performance at idle and under load of up to about 7 bar IMEP (indicated mean effective pressure) to the baseline under similar conditions. It has been proven that the elimination of metallic contact between the compression rings and cylinder wall takes place with a liner speed of 1.5-2.3 m/s surface speed (283-426 rpm for the 102 mm bore) for the 850-1280 rpm crankshaft speed. The RLE FMEP is substantially reduced under load, which is a trend opposite to
Dardalis, DimitriosHall, MatthewRiley, SebastianBasu, AmiyoMatthews, Ron
Aluminum oxide (Al₂O₃) nanoparticles are considered a promising fuel additive to enhance combustion efficiency, reduce emissions, and improve fuel economy. This study investigates the spray characteristics of diesel fuel blended with aluminum oxide nanoparticles in a constant volume chamber. The blends were prepared by dispersing Al₂O₃ nanoparticles in diesel at varying concentrations (25, 50, and 100 mg of aluminum oxide nanoparticles into 1 L of pure diesel, respectively) using a magnetic stirrer and ultrasonication to ensure stable suspensions. Spray characterization was conducted in a high-pressure and high-temperature constant volume chamber, simulating actual engine conditions. The ambient temperatures for this experiment were set from 800 to 1200 K, and the oxygen concentrations were set from 21% to 13%. The study focused on key spray parameters such as spray penetration length, spray angle, and spray area, analyzed using high-speed imaging and laser diffraction techniques
Ji, HuangchangZhao, Zhiyu
Camera-based mirror systems (CBMS) are being adopted by commercial fleets based on the potential improvements to operational efficiency through improved aerodynamics, resulting in better fuel economy, improved maneuverability, and the potential improvement for overall safety. Until CBMS are widely adopted it will be expected that drivers will be required to adapt to both conventional glass mirrors and CBMS which could have potential impact on the safety and performance of the driver when moving between vehicles with and without CBMS. To understand the potential impact to driver perception and safety, along with other human factors related to CBMS, laboratory testing was performed to understand the impact of CBMS and conventional glass mirrors. Drivers were subjected to various, nominal driving scenarios using a truck equipped with conventional glass mirrors, CBMS, and both glass mirrors and CBMS, to observe the differences in metrics such as head and eye movement, reaction time, and
Siekmann, AdamPrikhodko, VitalySujan, Vivek
In the modern automotive industry, improving fuel efficiency while reducing carbon emissions is a critical challenge. To address this challenge, accurately measuring a vehicle’s road load is essential. The current methodology, widely adopted by national guidelines, follows the coastdown test procedure. However, coastdown tests are highly sensitive to environmental conditions, which can lead to inconsistencies across test runs. Previous studies have mainly focused on the impact of independent variables on coastdown results, with less emphasis on a data-driven approach due to the difficulty of obtaining large volumes of test data in a short period, both in terms of time and cost. This paper presents a road load energy prediction model for vehicles using the XGBoost machine learning technique, demonstrating its ability to predict road load coefficients. The model features 27 factors, including rolling, aerodynamic, inertial resistance, and various atmospheric conditions, gathered from a
Song, HyunseungLee, Dong HyukChung, Hyun
Efficient and sustainable transportation in urban environments depends on understanding driving behaviors, and their implications. This study explores into the distinction between aggressive and non-aggressive driving patterns, leveraging an on-road driving dataset provided by an automotive company. By contrasting this data with established Fuel Economy cycles from United States Environmental Protection Agency (EPA) and employing curve-fitting techniques, the research not only reveals driving patterns but also predicts potential behaviors in unfamiliar scenarios. Results show significantly different acceleration profile patterns between different driving behaviors which has serious impact in fuel economy and environmental wellness. The findings highlights the environmental impact of driving behaviors, paving the way for environmentally responsible policy recommendations and sustainable driving practices.
Padmanaban, GandhimathiFeng, FredDai, EdwardSaini, AnkitHu, GuopengZhao, Yanan
Track testing methods are utilized in the automotive industry for emissions and fuel economy certification. These track tests are performed on smooth road surfaces which deteriorate over time due to wear and weather effects, hence warranting regular track repaves. The study focuses on the impact of repaving on track quality and surface degradation due to weather effects. 1D surface profiles and 2D surface images at different spatial frequencies were measured at different times over a span of two years using various devices to study the repave and degradation effects. Data from coastdown tests was also collected over a span of two years and is used to demonstrate the impact of track degradation and repaving on road load characterization parameters that are used for vehicle certification tests. Kernel density estimation and non-parametric spectral estimation methods are used to visualize the characteristic features of the track at different times. In the pre-processing stage, outliers
Singh, YuvrajJayakumar, AdithyaRizzoni, Giorgio
Honda Motor Corporation has developed a new naturally aspirated in-line 4-cylinder direct injection gasoline engine for C segment sedans that combines high environmental performance and power output. Development time and cost were greatly reduced by utilizing basic structures and components that had previously been developed engine for hybrid vehicles. In addition to the environmental performance at which hybrid engines excel, the driving performance required from a pure gasoline engine for C segment sedans with a low environmental impact was aimed to achieve by optimizing the shape of the combustion chamber to obtain rapid combustion, adjusting intake and exhaust valve timing, employing fuel injection control and adopting a two-piece water jacket that protects the exhaust system component by lowering the exhaust gas temperature at high load. As a result, the newly developed engine achieves a maximum thermal efficiency of 40% with knock suppression effect through rapid combustion
Kondo, TakashiOhmori, TakeyukiYamamoto, JunpeiMiki, Kentaro
Energy efficient configuration schemes are critical to the fuel economy and power of hybrid vehicles. Single planetary gear (PG) configurations are highly integrated, simple and reliable, but have limited fuel saving potential. To overcome these problems, a new multi-gear power split (PS) powertrain has been proposed because of their high efficiency and excellent overall performance. Only one PG and one synchronizer are required. In order to systematically explore all possible designs of multi-gear-PS hybrid designs, this paper proposes a topological tree graph method: 1) inspired by the “D” matrix automatic modeling method, a new configuration tree matrix is proposed, which is used to complete the isomorphism determination, mode feature classification, and dynamics modeling; a design synthesis method for the multi-gear PS configuration is investigated; 2) A new near-optimal energy management strategy, the improved Rapid-DP (IR-DP), is proposed for the fast computation of the near
Zou, YungeZhang, YuxinYang, Yalian
The natural wind experienced on public roads can increase the yaw angle and therefore drag coefficient (CD), which may contribute to the discrepancy between catalog fuel economy and actual fuel economy. The impact of yaw characteristics alone on fuel economy during actual driving has not been verified or proven as it is difficult to obtain actual driving data under uniform conditions. For this reason, shape optimization is normally performed at zero-yaw through the aerodynamic development phases. In this paper, two vehicles with different yaw sensitivity characteristics are driven simultaneously, and fuel economy measurements are performed simultaneously with ambient airflow, environment, and vehicle conditions. The results where the conditions of the two vehicles match are extracted to clarify the impact of the differences of yaw characteristics on fuel economy. The obtained results matched the values predicted by theoretical calculations for the impact of yaw angle on fuel economy
Onishi, YasuyukiNichols, LarryMetka, Mattmasumitsu, YasutakaInoue, Taisuke
The hybrid electric drive system has the potential to make a significant contribution to the energy sustainability of the automotive industry. This paper investigates the improved adaptive equivalent consumption minimization strategy (A-ECMS) for a multi-mode series-parallel hybrid electric vehicle. First, a basic ECMS algorithm for the series-parallel vehicle is established, which considers the instantaneous optimal torque matching in the electric, serial hybrid, and engine driving modes. Under the condition that the future traffic information scenario is known, it is desired to realize the global optimal planning based on the combination of dynamic programming (DP) and ECMS. The SOC, engine speed, and torque results calculated by the DP strategy are used as benchmarks to develop the improved SOC-AECMS and S-AECMS strategies, which better incorporate the advantages of the global optimization results. Finally, a hardware-in-the-loop simulation platform is set up to validate the real
Zhu, JingyuHan, MengweiLiu, ChongfanYang, ChenfanNishida, Keiya
In recent years, the stronger push for reducing GHG and NOx emissions has challenged vehicle manufacturers globally. In USA, Multi-Pollutant Emissions Standards for Model Years 2027 and Later Light Duty and Medium-Duty Vehicles released by EPA in April 2023 aims to reduce the CO2 emissions by 56% and 44%, respectively, for light and medium duty vehicles by 2032 from 2026 levels. It also includes the NMOG+ NOx standards, which require a 60 – 76% reduction by 2032 from 2026 levels for light to medium-duty vehicles. Europe also aims to reduce CO2 emissions by 55% by 2030 from 1990 levels and 100% by 2035. To achieve such low levels of CO2 emissions, especially in the near-term scenario of limited EV sales, hybridization of conventional powertrains has found renewed interest. While hybrid powertrains add complexity, if optimized well for the application, they can offer best tradeoff between upfront cost, range, payload, performance, emissions and off-ambient operation. This study
Fnu, DhanrajCorreia Garcia, BrunoPaul, SumitJoshi, SatyumFranke, Michael
An experimental study was conducted on a multi-cylinder engine equipped with both intake and exhaust continuously variable valve duration (CVVD). Due to CVVD and continuous variable valve timing (CVVT), valve closing and opening timings of both intake and exhaust sides became decoupled, so that four valve timings (opening and closing timings of intake as well as exhaust sides) can be optimized under each engine condition. Theses independent valve timings allowed reductions of fuel consumption as well as particle number (PN) and stoichiometry combustion under full-load condition without compromise of performance. In addition, to reduce raw gaseous emissions and shorten light-off time of catalyst under catalyst heating condition, various valve timings were tested in the engine test bench. As results, nitrogen oxides (NOx) – total hydrocarbon (THC) trade-off relation was relieved by optimal valve timings including negative valve overlap duration compared to the base engine. As the last
Jung, JinyoungHan, SangyeonPark, SangjaeKwon, Ki YoungSon, YousangKim, Back-SikKim, Youngnam
Optimizing energy providers like fuel cells and engines involves considering various factors, constraints, and requirements. These include NVH (Noise, Vibration, and Harshness), durability, operating point efficiency, and customer expectations. Different energy providers prioritize these factors differently. For instance, NVH is crucial for engines due to customer expectations regarding start-up, sound, and power delivery based on accelerator input. In contrast, fuel cells face fewer constraints but must consider noise from electrical AC compressors and other devices, especially at lower vehicle speeds. However, operating point efficiency and durability are paramount for fuel cells, as they are expected to last as long as engines in conventional vehicles sold today. This paper proposes a holistic approach that begins at the vehicle or powertrain architecture level and designs an operating strategy that integrates all the aforementioned factors to enhance the operation of a fuel cell
Patel, NadirshKudupley, Harshal
This study evaluates the impacts of the gasoline compression ignition (GCI) engine on heavy duty long-haul trucks in both the Chinese and US markets. The study examines various aspects such as vehicle performance requirements, fuel consumption, emissions, and ownerships costs, and how they influence the implementation and impact of new technologies in these markets. By considering a wide variety of drive cycles, including standard regulatory cycles and real-world cycles, the study aims to identify the impact of varying degrees of powertrain electrification using diesel and GCI engines on fuel consumption and emissions. Additionally, this paper explores the viability of powertrain electrification in long-haul trucks by analyzing factors such as levelized cost of driving (LCOD), manufacturing costs, and energy costs. These considerations play a crucial role in determining the economic feasibility and attractiveness of electrification technologies in various driving scenarios and market
Nieto Prada, DanielaVijayagopal, RamYan, ZimingSari, RafaelHe, Xin
Nowadays, hydrogen (H2) is rising as a key solution to fuel internal combustion engines (ICE) since it allows carbon free combustion process. At the same time, ICE fueled with H2 can reach similar performance and driving experience of gasoline fueled ones. In stoichiometric conditions, hydrogen shows higher flame speed, lower ignition energy and lower quenching distance than gasoline. Mainly for these reasons, H2 combustion is characterized by a high risk of abnormal combustion (i.e. knock and pre-ignition), relevant NOx emissions and high heat losses. On the other hand, the wide flammability range and high combustion stability of H2 allow the use of different techniques to reduce combustion reactivity. This work presents a combined approach, experimental and numerical, to assess the benefits of three mixture dilution methods. The experimental campaign, in different operating conditions, was carried out on a production derived high specific power gasoline Single Cylinder Engine (SCE
Tonelli, RobertoMedda, MassimoGullino, FabrizioSilvestri, NicolaZaffino, FrancescoMariconti, RobertoRossi, Vincenzo
Fuel economy and the ability to maintain the state of charge (SOC) of the battery are two key metrics for the energy management of a full-power fuel cell hybrid vehicle fitted with a small-capacity battery pack. To achieve stable maintenance of SOC and near-optimal fuel consumption, this paper proposes an adaptive equivalent consumption minimization strategy (PA-ECMS) based on power prediction. The strategy realizes demand power prediction through a hybrid deep learning model, and periodically updates the optimal equivalent factor (EF) based on the predicted power to achieve SOC convergence and ensure fuel economy. Simulation results show that the hybrid deep learning network model has high prediction accuracy with a root mean square error (RMSE) of only 0.733 m/s. Compared with the traditional ECMS based on SOC feedback, the PA-ECMS effectively maintains the battery SOC in a more reasonable range, reduces the situation of the fuel cell directly charging the power cell in the high
Gao, XinyuJu, FeiChen, GangZong, YuhuaWang, Liangmo
As the agricultural industry seeks to enhance sustainability and reduce operational costs, the introduction of mild hybrid technology in tractors presents a promising solution. This paper focuses on downsizing internal combustion (IC) engine, coupled with integration of electric motor, to reduce fuel consumption and meet stringent emission regulations while maintaining power requirement for agricultural applications in India. The hybridization aims to deliver instant power boosts during peak loads and capitalizes on energy recovery during part loads and braking. Furthermore, the idle avoidance feature minimizes fuel consumption during periods of inactivity thus improving fuel efficiency. The hybridization also aims to hybridize auxiliary systems for flexible power management, enabling operation of either engine, auxiliaries, or both as needed. A newly developed hybrid supervisory control prototype efficiently manages electric power and mechanical power, enabling intelligent management
Prasad, Lakshmi P.PS, SatyanarayanaPaygude, TejasGangsar, PurushottamThakre, MangeshChoudhary, NageshGitapathi, Ajinkya
The rapid advancement of alternative energy and energy-saving technologies in China underscores the importance of conducting a comprehensive analysis of the total cost of ownership (TCO) for commercial vehicles such as buses and trucks. To address the challenges of quantifying time-sensitive and implicit costs, this study has developed an extensive database and a web-based modeling tool to evaluate the TCO of these vehicles for the period 2020–2040. The tool allows for user-customized inputs and generates TCO estimates across multiple technology evolution scenarios, encompassing nearly 200 vehicle types categorized by class, intended use, and powertrain technology, within diverse technology development pathways. The model integrates critical cost factors, including vehicle purchase costs, financing costs, energy expenditures, and inconvenience costs, providing a detailed assessment of long-term ownership costs. Key findings indicate that under the reference scenario, battery electric
Tan, XiaoluOu, Shiqi(Shawn)Wu, ShuhongChen, YongjianLin, Zhenhong
A major portion of the energy consumed in a vehicle is spent on keeping the occupants thermally comfortable in all environmental conditions when the heating, ventilation, and air-conditioning (HVAC) system is turned on. Maintaining the thermal comfort of a passenger is critical in terms of fuel consumption and emission for internal combustion engine (ICE) vehicles. In electrified vehicles, where range is of major concern, this gains further-more importance. SC03 is a test defined by the US Environmental Protection Agency (EPA) to measure tailpipe emissions and fuel economy of passenger cars with the air-conditioner on. The current study would focus on this drive cycle on an ICE vehicle. The co-simulation framework would include a 1D thermal system model, associated thermal controls, a vehicle cabin model, and a human thermal model. 1D model will be predicting the energy consumption via compressor power, refrigerant pressure and temperature across the loop, component heat rejection, etc
Natarajan, ShankarBalasubramanian, Sudharsan
China Automotive Engineering Research Institute Co., Ltd (CAERI) has completed a new vehicle aero-acoustic wind tunnel (AAWT), which is located in Chongqing, China, and has been in operation for 5 years. To help addressing the Chinese vehicle market’s need to improve fuel economy, reduce exhaust emissions, and decrease product development period, the wind tunnel was designed and implemented to achieve a high degree of automation for vehicle testing next to a high aerodynamic and acoustic test accuracy for product development. The CAERI wind tunnel was in operation in June 2019, achieving a top speed of 250 km/h. A 5-belt rolling road system with a long center belt for proper wake simulation is installed inside, a test section with very low static pressure gradient and background noise. Wind tunnel calibration and customized measurement activities can be performed with an overhead traversing system. In the present paper, the main facilities of the AAWT are described next to necessary
Xu, LeiZhu, XijiaWang, QingyangBu, HanPeng, ChaoShi, FengYang, ChaoHuang, TaoZeng, YiZeng, XiangyiWallmann, SteffenMünstermann, HenningWittmeier, FelixMercker, EdzardBlumrich, Reinhard
In hybrid electric vehicles (HEVs), optimizing energy management and reducing system losses are critical for enhancing overall efficiency and performance. This paper presents a novel control strategy for the boost converter in hybrid electric vehicles (HEVs), aimed at minimizing energy losses and optimizing performance by modulating to a higher boost converter voltage only when necessary. Traditional approaches to boost converter control often lead to unnecessary energy consumption by maintaining higher voltage levels even when not required. In contrast, the proposed strategy dynamically adjusts the converter's operation based on real-time vehicle demands, such as driver input, Engine Start-Stop (ESS) events, Active Electric Motor Damping (AEMD), entry and exit transitions for Engine Fuel Cut-Off (DFCO), Noise-Vibration-Harshness (NVH) events like lash-zone crossing and other specific operational conditions. The control strategy leverages predictive algorithms and real-time monitoring
Basutkar, AmeyaHuo, ShichaoSullivan, ClaireBerger, DanielTischendorf, Christoph
Effective traffic management and energy-saving techniques are increasingly needed as metropolitan areas grow and traffic volumes rise. This work estimates fuel consumption over three selected routes in an urban context using spatio-temporal modeling essentially building on a previously developed approach in traffic prediction and forecasting. A weighted adjacency matrix for a Graph Neural Network (GNN) is constructed in the original approach which combines graph theory frameworks with travel times obtained from average speeds and distances between traffic count stations. Next, the traffic flow estimate uncertainty is measured using Adaptive Conformal Prediction (ACP) to provide a more reliable forecast. This work predicts fuel consumption under different scenarios by utilizing Monte Carlo simulations based on the expected traffic flows providing insights into energy efficiency and the best routes to take. The study compares passenger vehicles' and heavy-duty trucks' mean fuel
Patil, MayurMoon, JoonHanif, AtharAhmed, Qadeer
The automotive aerodynamic development relies on wind tunnel testing and Computational Fluid Dynamics (CFD), where the former provides reliable values to be used for fuel economy calculations, and the latter enables the investigation of flow features responsible for improvement/degradation of the average large-scale performances in terms of aerodynamic coefficients. The abovementioned procedure overlooks a crucial factor however: natural wind. The speed and the direction of natural wind encountered while driving alters the vehicle’s effective yaw angle. Such condition implies that the minimization of the drag coefficient at zero-yaw, commonly performed through wind tunnel and CFD simulations in an industrial context, may not yield real-world optimal shapes. While it is possible to reproduce natural wind-like conditions in a wind tunnel using flaps, for example, the input signal to the flap system must be available beforehand, and such key element is the focus of the present research
Nucera, FortunatoOnishi, YasuyukiMetka, Matt
Reducing emissions in individual transport requires electrification and hybridization. Emission reduction depends on the degree of electrification, the specific powertrain design and optimized components. This is especially true for hybrids with the highest number of components, consisting of combustion engine, transmission, electric motors and batteries. The integration of the electric motor in the transmission for dedicated hybrid transmissions leads to many possible concepts. Computer-aided powertrain synthesis is therefore needed to develop new powertrain architectures. In a publicly funded project, we have developed a powertrain synthesis that includes a combustion engine synthesis and a transmission synthesis. In this paper we focus on the impact of the engine concept on the powertrain dimensioning, fuel consumption, performance and operating behavior in a parallel hybrid configuration. In addition to different engine concepts, the electrical power is also varied to discuss the
Sturm, AxelHenze, RomanKüçükay, FeritWolgast, CarstenEilts, Peter
In hybrid vehicle systems, the addition of a clutch at the engine end can significantly enhance the overall energy efficiency of the vehicle. In this paper, a novel multi-mode series-parallel configuration is proposed based on the Honda IMMD system and a comprehensive comparison is made with series and series-parallel configurations. Firstly, this paper analyses the various operational modes induced by the inclusion of a clutch at the engine end based on the IMMD system. Subsequently, the fuel consumption of the novel optimized series-parallel configuration is assessed using a rapid dynamic programming method aimed at minimizing fuel consumption during the powertrain operation; additionally, its dynamic performance is analyzed through dynamic programming algorithms. Finally, the performance of different configurations is quantitatively evaluated in terms of acceleration and fuel consumption. The findings reveal that the IMMD + Clutch configuration significantly enhances dynamic
Zhang, YuxinZou, YungeYang, Yalian
Carbon neutrality has become a global initiative, prompting automobile manufacturers to introduce electrified vehicles such as HEVs, PHEVs, BEVs, and FCEVs. Although interest in BEVs is rising, HEVs, PHEVs, and other internal combustion engine vehicles are expected to remain in use in regions where transitioning to BEVs is challenging. For these vehicles, low-viscosity engine oil is a key measure to further reduce CO2 emissions. Moreover, high-efficiency engines in electrified vehicles typically operate at lower oil temperatures than conventional engines due to reduced thermal loss to coolant and oil. Lowering viscous resistance in the mid- to low-temperature range below 80°C is significant for improving fuel economy. However, viscosity must be maintained above a certain level to ensure the performance of hydraulic devices at higher temperatures. To achieve both characteristics, oils with a low temperature dependence of viscosity (ultra-high viscosity index) are required. This
Yamamori, KazuoHirano, SatoshiYoshida, SatoruMatsui, Noriyuki
Renewable Gasoline Blends can deliver greater than 50% reduction in vehicle Well-to-Wheel (WtW) greenhouse gas emissions when used in current vehicles. When paired with a state-of-the-art hybrid vehicle (relative to an average vehicle on U.S. roads today), a greater than 70% reduction in WtW emissions can be achieved. Importantly, Renewable Gasoline Blends can be formulated to align with existing market standards for gasoline, thereby functioning as a drop-in fuel solution compatible with all gasoline-powered vehicles. Renewable Gasoline Blends can also be formulated with higher ethanol blend ratios to meet a variety of fuel grades and market standards. These varying formulations can result in tradeoffs across engine performance, fuel economy, and potentially cost. For example, higher ethanol blends investigated lead to slight decreases in fuel economy across FTP, HWFE, and US06 cycles (typically ~1 - 2%, despite 2 – 5% lower heating values); however, significant decreases in PM
Vuilleumier, DavidMorlan, BrianOhta, SatoshiLoeper, PaulLorenz, RobertTakada, KeishiSugata, KenjiMatsubara, NaoyoshiTakahashi, Daishi
Employing multibody dynamic simulations with semi-empirical tire models is widely recognized as a cost-effective approach. A recent development introduces a novel road and tire-soil contact model that is not only swift and memory-efficient but also addresses limitations in classical semi-empirical models. This study conducts a thorough validation of the new road and contact model by creating a detailed multibody model of the four-wheeled vehicle, Fuel Efficiency Demonstrator (FED) – Alpha, integral to NATO's Next-Generation reference mobility model. The comprehensive model encompasses the chassis, suspension, tires, engine, transmission and various other components. Through simulations of various driving scenarios, accounting for complex terrain geometries, spatially varying soil properties, and multi-pass phenomena, the model's performance is evaluated. The simulation results are compared with physical measurements, providing a detailed assessment of the tire-soil model's predictive
Papapostolou, LamprosKoutras, EvangelosLeila, FelipeRibaric, AdrijanNatsiavas, Sotirios
This paper explores a parameter optimization calculation method for a dual-motor coupled integrated single-axle drive system, aiming to achieve the optimal balance between vehicle dynamics, fuel efficiency, and system efficiency under this configuration. By constructing a vehicle longitudinal dynamics model and referencing motor models, the effective operating range is calculated. Vehicle acceleration time, gradeability, and maximum speed are used as constraints, while the proportion of the high-efficiency operating area of the drive system is taken as the objective function for optimizing relevant system parameters. This method improves computational efficiency by dividing the contour lines, thus eliminating the need to traverse all points in the constraint area and converting them into an intuitive analysis of the operating range, which reduces the need for point-by-point calculations across the entire working area.
Gu, ZhuangzhuangYou, JianhuiWu, JinglaiZhang, Yunqing
Upcoming California Tier 5 non-road limits mandate 90% and 75% reductions in NOx and PM respectively, from current Tier 4F emission standards. Similarly, lower NOx and PN/PM limits can be expected from a next round of European Non-Road regulations. To meet these limits, more SCR volume for greater NOx reduction, and better filtration efficiency filters for greater PN/PM reduction, may be required. The challenge is to accommodate larger SCR volume while maintaining oxidation (DOC) and filtration (DPF) functionality of the aftertreatment system within a limited packaging space on non-road machineries. Consolidating DOC and DPF into a single component as DOC-on-filter instead of separate DOC and DPF substrates to achieve space saving has been previously discussed in literature. This study expands on the current understanding and explores various functional performance characteristics of the DOC-on-filter concept in comparison with DOC + bare DPF, DOC + PGM coated DPF. The three test
Dam, MrinmoyWarkins, JasonHe, Suhao
Combining a low-carbon content fuel, such as natural gas, with a high-efficiency engine can reduce greenhouse gas emissions significantly in hard-to-electrify long-haul trucking applications. Turbo-compounding, where an additional power turbine is installed in the exhaust stream after the turbocharger turbine, can extract useful amounts of energy from diesel engine exhaust at high loads. This work assesses the net benefits of combining turbo-compounding with a high-efficiency, natural gas fuelled heavy-duty engine. The effects on brake specific fuel consumption (BSFC), greenhouse gas emissions, and engine-out emissions of nitrogen oxides (NOx) and methane (CH4) are considered. The experimentally validated 1D model for a 13L diesel pilot- direct injection of natural gas, heavy-duty engine in GT-SUITETM is used to develop a series turbo-compound model. The effects of turbine sizes and flow capacities in fixed-geometry turbocharging and power turbines are evaluated on the engine’s
Balazadeh, NavidMunshi, SandeepShahbakhti, MahdiMcTaggart-Cowan, Gordon
This work aims to design an ecological driving strategy for connected and automated vehicles (CAVs) at an isolated signalized intersection in a mixed traffic flow of CAVs and human-driven vehicles (HVs). Actually, from existing experiments and theories, we can obtain that stochasticity of HVs plays a nontrivial role in traffic flow, including the drivers’ driving personality style and the interaction between HV and CAV. To consider the uncertainty of HVs, we propose driver acceptance to describe the interaction between HV and CAV with the increase of CAV market penetration rate (MPR). Then, to estimate the arrival time of CAV accurately, we propose an improved LWR method integrating the vehicle to V2X data and detector data. The problem is formulated as a multi-objective optimization model and solved by NSGA-II. Our study indicates that multi-objective performance benefits depend on inflow rate, the MPR, and the drivers’ acceptance towards CAVs. The results show that traffic efficiency
Wang, XiaoliangMa, ShufangYu, QinSong, WenPeng, HongruiHu, Yiming
The practice of vehicle platooning for managing mixed traffic can greatly enhance safety on the roads, augment overall traffic flow, and boost fuel efficiency, garnering considerable focus in transportation. Existing research on vehicle platoon control of mixed traffic has primarily focused on using the state information of the leading or head vehicle as control input for following vehicles without accounting for the driving variability of Human-driven Vehicles (HDVs), which does not conform to the driving conditions of vehicles in reality. Inspired by this, this paper presents a car-following model for Connected and Automated Vehicles (CAVs) that utilizes communication with multiple preceding vehicles in mixed traffic. The study further investigates the impact of parameters such as the speed and acceleration of preceding vehicles on the car-following behavior of CAVs, as well as the overall effect of different CAV penetration rates on mixed traffic flow. Firstly, a mixed-vehicle
Peng, FukeHuang, Xin
This study investigates the thermal buckling behavior of axially layered functionally graded material (FGM) thin beams with potential applications in automotive structures. The FGM beam is constructed from four axially stratified sections, with the proportional amount of metal and ceramic fluctuating through the thickness. The buckling analysis is carried out for three different support configurations: clamped-clamped, simply supported-simply supported, and clamped-simply supported. The primary objective is to identify the optimal thermal buckling temperature of the FGM thin beam using the Taguchi optimization method. Beam arrangements are established using a Taguchi L9 orthogonal array and analyzed using finite element software (ANSYS). Layers 1-4 of the axially layered beam are considered process parameters, while the thermal buckling temperature is the response parameter. Minitab software performs an Analysis of Variance (ANOVA) with a 95% confidence level to identify the most
Pawale, DeepakBhaskara Rao, Lokavarapu
This paper studies the effect of single vacancy defect on the fundamental frequency of carbon nanotube using finite element method. Cantilevered and bridged boundary conditions have been used for carbon nanotube with and without attached mass. There is less effect on the frequency of cantilevered structure due to presence of defect at center rather than its presence at other positions. Presence of defect near to fixed end shows more effect on fundamental frequency of bridged structure as opposed to other positions. Cantilevered structure with mass attached shows increase in effect due to presence of defect when mass ranges from 10-3 to 10-6 femtogram, while it seems to remain constant with further decrease in mass. This paper is mainly concerned about the overall effect of single vacancy defect at the different positions and with different parameters of carbon nanotube with and without attached mass on the frequency and frequency shift. Nano materials are playing a vital role in all
Kharche, GauravBhaskara Rao, LokavarapuB, SrivatsanBalakrishna Sriganth, PranavBiswas, Sayan
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, GoutamBiswas, Sanjoy
Parallel hybrid commercial vehicles equipped with automated manual transmissions are extensively utilized in the commercial vehicle sector due to their minimal configuration changes, high energy efficiency, and multi-mode driving capabilities. The key to enhancing the fuel economy of these vehicles lies in the mode switching and gear shift control strategy. To meet the driving requirements of these vehicles and optimize their fuel efficiency, this study introduces a mode switching and gear shift control strategy based on dynamic programming for a parallel hybrid commercial vehicle. First, dynamic programming is applied to the energy management strategy of the hybrid electric vehicle to determine the optimal fuel-efficient power output. Subsequently, the results from dynamic programming simulations are utilized to establish the mode switching boundaries and gear shift patterns. An improved mode switching and gear shift control strategy is then proposed and compared with the control
Zhai, XumaoLi, YujuanJiang, GuangzongYan, ZhengfengYao, MingyaoSun, Yansen
Items per page:
1 – 50 of 7810