Pub Date : 2024-02-01DOI: 10.1177/09544070241231517
{"title":"Corrigendum to Thermodynamic Analysis of Heat Transfer Reduction in Spark Ignition Using Thermal Barrier Coatings. Proceedings of the Institution of Mechanical Engineers, Part D: Journal of Automobile Engineering. Epub ahead of print 7 August 2023. DOI: 10.1177/09544070231189545","authors":"","doi":"10.1177/09544070241231517","DOIUrl":"https://doi.org/10.1177/09544070241231517","url":null,"abstract":"","PeriodicalId":509770,"journal":{"name":"Proceedings of the Institution of Mechanical Engineers, Part D: Journal of Automobile Engineering","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139884097","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-02-01DOI: 10.1177/09544070241231517
{"title":"Corrigendum to Thermodynamic Analysis of Heat Transfer Reduction in Spark Ignition Using Thermal Barrier Coatings. Proceedings of the Institution of Mechanical Engineers, Part D: Journal of Automobile Engineering. Epub ahead of print 7 August 2023. DOI: 10.1177/09544070231189545","authors":"","doi":"10.1177/09544070241231517","DOIUrl":"https://doi.org/10.1177/09544070241231517","url":null,"abstract":"","PeriodicalId":509770,"journal":{"name":"Proceedings of the Institution of Mechanical Engineers, Part D: Journal of Automobile Engineering","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139824238","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-01-29DOI: 10.1177/09544070241227092
Guozhen Li, Wankai Shi
Designing a secure and reliable decision-planning model for vehicle lane changing is of utmost practical significance because it is one of the most frequent driving behaviors and has a substantial impact on the safety of drivers’ lives and property. First, a Gaussian mixed Hidden Markov model (GMHMM) is trained for lane change intention recognition (LCIR), and the results reveal that the model has a great performance. This will simplify the game process and provide drivers and passengers with warnings. Second, the safety, efficiency, and comfort payoffs of vehicle lane changes are taken into account when building the game model. When building the safety payoff function, temporal collision risk and spatial collision risk of vehicles are two of them that are carefully taken into account. After that, the vehicle’s trajectory tracking control is decoupled into lateral LQR + feedforward control and longitudinal dual proportional integral derivative (PID) control based on the Frenet coordinate system. Finally, a vehicle lane change scenario is built for simulation analysis, and the effects of driving comfort factor and driving efficiency factor on lane change results are considered. The results show that the proposed game theory lane change model ensures lane change safety while satisfying human drivers’ requirements for lane change efficiency and comfort.
{"title":"Research on lane-changing decision and control of autonomous vehicles based on game theory","authors":"Guozhen Li, Wankai Shi","doi":"10.1177/09544070241227092","DOIUrl":"https://doi.org/10.1177/09544070241227092","url":null,"abstract":"Designing a secure and reliable decision-planning model for vehicle lane changing is of utmost practical significance because it is one of the most frequent driving behaviors and has a substantial impact on the safety of drivers’ lives and property. First, a Gaussian mixed Hidden Markov model (GMHMM) is trained for lane change intention recognition (LCIR), and the results reveal that the model has a great performance. This will simplify the game process and provide drivers and passengers with warnings. Second, the safety, efficiency, and comfort payoffs of vehicle lane changes are taken into account when building the game model. When building the safety payoff function, temporal collision risk and spatial collision risk of vehicles are two of them that are carefully taken into account. After that, the vehicle’s trajectory tracking control is decoupled into lateral LQR + feedforward control and longitudinal dual proportional integral derivative (PID) control based on the Frenet coordinate system. Finally, a vehicle lane change scenario is built for simulation analysis, and the effects of driving comfort factor and driving efficiency factor on lane change results are considered. The results show that the proposed game theory lane change model ensures lane change safety while satisfying human drivers’ requirements for lane change efficiency and comfort.","PeriodicalId":509770,"journal":{"name":"Proceedings of the Institution of Mechanical Engineers, Part D: Journal of Automobile Engineering","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-01-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140486662","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-01-29DOI: 10.1177/09544070241227266
Xianjian Jin, Qikang Wang, Zeyuan Yan, Hang Yang, Guodong Yin
This paper presents an integrated robust H∞ control strategy for improving path following performance and lateral stability of autonomous in-wheel-motor-driven electric vehicles (AIEV) through integration of active front steering (AFS) and direct yaw moment control system (DYC). The AIEV system dynamics and its uncertain vehicle trajectory following system are first modeled, in which parameter uncertainties related to the physical limits of tire are considered and handled via the norm-bounded uncertainties, then the control-oriented vehicle path following augmented system with dynamic errors is developed. The resulting robust H∞ controller with AFS and DYC (RHCAD) of AIEV trajectory-following system is finally designed, and solved utilizing a set of linear matrix inequalities derived from quadratic H∞ performance and Lyapunov stability. Meanwhile, the performance index of H∞ norm from external disturbance to controlled output for AIEV path following is attenuated while other system requirements such as parameter uncertainties, system constraints are also guaranteed in controller design, and then the quadratic D-stability is also utilized to enhance the transient response of the closed-loop AIEV system. Simulations for J-shaped, single lane change and double lane change maneuvers are carried out to verify the effectiveness of the proposed controller with a high-fidelity, CarSim®, full-vehicle model. It can be concluded from the results that the proposed robust H∞ control strategy integrating AFS and DYC can improve the path following performance and lateral stability of AIEV compared with traditional linear quadratic regulator controller with AFS (LQRA) and robust H∞ controller with AFS (RHCA).
{"title":"Integrated robust control of path following and lateral stability for autonomous in-wheel-motor-driven electric vehicles","authors":"Xianjian Jin, Qikang Wang, Zeyuan Yan, Hang Yang, Guodong Yin","doi":"10.1177/09544070241227266","DOIUrl":"https://doi.org/10.1177/09544070241227266","url":null,"abstract":"This paper presents an integrated robust H∞ control strategy for improving path following performance and lateral stability of autonomous in-wheel-motor-driven electric vehicles (AIEV) through integration of active front steering (AFS) and direct yaw moment control system (DYC). The AIEV system dynamics and its uncertain vehicle trajectory following system are first modeled, in which parameter uncertainties related to the physical limits of tire are considered and handled via the norm-bounded uncertainties, then the control-oriented vehicle path following augmented system with dynamic errors is developed. The resulting robust H∞ controller with AFS and DYC (RHCAD) of AIEV trajectory-following system is finally designed, and solved utilizing a set of linear matrix inequalities derived from quadratic H∞ performance and Lyapunov stability. Meanwhile, the performance index of H∞ norm from external disturbance to controlled output for AIEV path following is attenuated while other system requirements such as parameter uncertainties, system constraints are also guaranteed in controller design, and then the quadratic D-stability is also utilized to enhance the transient response of the closed-loop AIEV system. Simulations for J-shaped, single lane change and double lane change maneuvers are carried out to verify the effectiveness of the proposed controller with a high-fidelity, CarSim®, full-vehicle model. It can be concluded from the results that the proposed robust H∞ control strategy integrating AFS and DYC can improve the path following performance and lateral stability of AIEV compared with traditional linear quadratic regulator controller with AFS (LQRA) and robust H∞ controller with AFS (RHCA).","PeriodicalId":509770,"journal":{"name":"Proceedings of the Institution of Mechanical Engineers, Part D: Journal of Automobile Engineering","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-01-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140487251","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-01-29DOI: 10.1177/09544070241228643
Hong Zhang, Zan-Sheng Zheng, Hailiang Yu, Gang Yang, Shengdong Yuan
In response to the limitations of traditional offline static simulation modeling technology in accurately addressing the intricacies and complexities of intelligent and connected vehicles (ICVs) driving processes, this paper introduces the concept of an ICV driving system (ICVDS) model based on digital twin technology. Firstly, the paper delves into the theory of ICVDS digital twin modeling, covering aspects such as model elements and the operational mechanism of the model. The ICVDS, which relies on digital twin (DT) technology, is designed in accordance with the characteristics of ICVs, their technical requirements, and the architecture of the DT system. Subsequently, the paper explores four key areas: the modeling of driving elements, the modeling of the driving process, simulation modeling of the driving process, and a summary of modeling technology. The section on modeling driving elements primarily elucidates the methodology for creating twin models and illustrates how these models describe the system’s functionality in controlling the subject. The segment on modeling the driving process elucidates the approach to real-time data-driven modeling. The part on driving process simulation modeling explains the methodology for establishing simulation models and demonstrates how they predict the future state of the subject. Lastly, the paper introduces the construction of autonomous driving test scenarios based on ICVDS.
{"title":"Analysis of intelligent and connected vehicles driving system modeling","authors":"Hong Zhang, Zan-Sheng Zheng, Hailiang Yu, Gang Yang, Shengdong Yuan","doi":"10.1177/09544070241228643","DOIUrl":"https://doi.org/10.1177/09544070241228643","url":null,"abstract":"In response to the limitations of traditional offline static simulation modeling technology in accurately addressing the intricacies and complexities of intelligent and connected vehicles (ICVs) driving processes, this paper introduces the concept of an ICV driving system (ICVDS) model based on digital twin technology. Firstly, the paper delves into the theory of ICVDS digital twin modeling, covering aspects such as model elements and the operational mechanism of the model. The ICVDS, which relies on digital twin (DT) technology, is designed in accordance with the characteristics of ICVs, their technical requirements, and the architecture of the DT system. Subsequently, the paper explores four key areas: the modeling of driving elements, the modeling of the driving process, simulation modeling of the driving process, and a summary of modeling technology. The section on modeling driving elements primarily elucidates the methodology for creating twin models and illustrates how these models describe the system’s functionality in controlling the subject. The segment on modeling the driving process elucidates the approach to real-time data-driven modeling. The part on driving process simulation modeling explains the methodology for establishing simulation models and demonstrates how they predict the future state of the subject. Lastly, the paper introduces the construction of autonomous driving test scenarios based on ICVDS.","PeriodicalId":509770,"journal":{"name":"Proceedings of the Institution of Mechanical Engineers, Part D: Journal of Automobile Engineering","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-01-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140488133","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-01-29DOI: 10.1177/09544070241227101
G. Kahandawa, Ian Spark, Amal Jayawardena
Cooperative redundancy of multiple steering systems are used to maximise traction, manoeuvrability and stability of a wheeled vehicle operating on difficult terrain. Cooperative redundancy is achieved if all the wheel angle steering effects and the drive wheel speed steering effects have a single theoretical instant centre. This means they all reinforce each other without conflict. This maximises energy efficiency and minimises ground damage and tyre wear. In previous work, close coupled wheel motors where used to drive the wheels. In this work, each wheel is connected to the output shaft of a reverse differential. The primary input to each differential is by means of a mechanical shaft drive which delivers power from the vehicle gearbox to each reverse differential. The secondary input to each reverse differential is provided by a hydrostatic motor which is used to correct the speed of each wheel in order to achieve cooperative redundancy. The hydrostatic motors will only be driven when the vehicle is turning. The hydrostatic motors will be stationary when the vehicle is proceeding in a straight line. Equations for the correct speed of the hydrostatic motors are derived. If the vehicle is to be capable of turning about any instant centre, the wheels must be capable of turning through a large angle range. The necessary range is 180° if the wheels can be driven in both forward and reverse directions. A mechanical drive to such wheels is only feasible if a vertical kingpin drive is involved. However, such a drive suffers from an inevitable but unwanted coupling between the turning of the wheel and the rotation of the wheel. Means of compensating for this unwanted effect are also described.
{"title":"Vehicles with cooperative redundancy of multiple steering systems: A hybrid shaft/hydrostatic drive system","authors":"G. Kahandawa, Ian Spark, Amal Jayawardena","doi":"10.1177/09544070241227101","DOIUrl":"https://doi.org/10.1177/09544070241227101","url":null,"abstract":"Cooperative redundancy of multiple steering systems are used to maximise traction, manoeuvrability and stability of a wheeled vehicle operating on difficult terrain. Cooperative redundancy is achieved if all the wheel angle steering effects and the drive wheel speed steering effects have a single theoretical instant centre. This means they all reinforce each other without conflict. This maximises energy efficiency and minimises ground damage and tyre wear. In previous work, close coupled wheel motors where used to drive the wheels. In this work, each wheel is connected to the output shaft of a reverse differential. The primary input to each differential is by means of a mechanical shaft drive which delivers power from the vehicle gearbox to each reverse differential. The secondary input to each reverse differential is provided by a hydrostatic motor which is used to correct the speed of each wheel in order to achieve cooperative redundancy. The hydrostatic motors will only be driven when the vehicle is turning. The hydrostatic motors will be stationary when the vehicle is proceeding in a straight line. Equations for the correct speed of the hydrostatic motors are derived. If the vehicle is to be capable of turning about any instant centre, the wheels must be capable of turning through a large angle range. The necessary range is 180° if the wheels can be driven in both forward and reverse directions. A mechanical drive to such wheels is only feasible if a vertical kingpin drive is involved. However, such a drive suffers from an inevitable but unwanted coupling between the turning of the wheel and the rotation of the wheel. Means of compensating for this unwanted effect are also described.","PeriodicalId":509770,"journal":{"name":"Proceedings of the Institution of Mechanical Engineers, Part D: Journal of Automobile Engineering","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-01-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140489977","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Present the DDPGwP (DDPG with Pretraining) model, grounded in the framework of deep reinforcement learning, designed for autonomous driving decision-making. The model incorporates imitation learning by utilizing expert experience for supervised learning during initial training and weight preservation. A novel loss function is devised, enabling the expert experience to jointly guide the Actor network’s update alongside the Critic network while also participating in the Critic network’s updates. This approach allows imitation learning to dominate the early stages of training, with reinforcement learning taking the lead in later stages. Employing experience replay buffer separation techniques, we categorize and store collected superior, ordinary, and expert experiences. We select sensor inputs from the TORCS (The Open Racing Car Simulator) simulation platform and conduct experimental validation, comparing the results with the original DDPG, A2C, and PPO algorithms. Experimental outcomes reveal that incorporating imitation learning significantly accelerates early-stage training, reduces blind trial-and-error during initial exploration, and enhances algorithm stability and safety. The experience replay buffer separation technique improves sampling efficiency and mitigates algorithm overfitting. In addition to expediting algorithm training rates, our approach enables the simulated vehicle to learn superior strategies, garnering higher reward values. This demonstrates the superior stability, safety, and policy-making capabilities of the proposed algorithm, as well as accelerated network convergence.
{"title":"A decision-making of autonomous driving method based on DDPG with pretraining","authors":"Jinlin Ma, Mingyu Zhang, Kaiping Ma, Houzhong Zhang, Guoqing Geng","doi":"10.1177/09544070241227303","DOIUrl":"https://doi.org/10.1177/09544070241227303","url":null,"abstract":"Present the DDPGwP (DDPG with Pretraining) model, grounded in the framework of deep reinforcement learning, designed for autonomous driving decision-making. The model incorporates imitation learning by utilizing expert experience for supervised learning during initial training and weight preservation. A novel loss function is devised, enabling the expert experience to jointly guide the Actor network’s update alongside the Critic network while also participating in the Critic network’s updates. This approach allows imitation learning to dominate the early stages of training, with reinforcement learning taking the lead in later stages. Employing experience replay buffer separation techniques, we categorize and store collected superior, ordinary, and expert experiences. We select sensor inputs from the TORCS (The Open Racing Car Simulator) simulation platform and conduct experimental validation, comparing the results with the original DDPG, A2C, and PPO algorithms. Experimental outcomes reveal that incorporating imitation learning significantly accelerates early-stage training, reduces blind trial-and-error during initial exploration, and enhances algorithm stability and safety. The experience replay buffer separation technique improves sampling efficiency and mitigates algorithm overfitting. In addition to expediting algorithm training rates, our approach enables the simulated vehicle to learn superior strategies, garnering higher reward values. This demonstrates the superior stability, safety, and policy-making capabilities of the proposed algorithm, as well as accelerated network convergence.","PeriodicalId":509770,"journal":{"name":"Proceedings of the Institution of Mechanical Engineers, Part D: Journal of Automobile Engineering","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-01-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140487641","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-01-28DOI: 10.1177/09544070241227094
Jifa Yan, Tao Deng, Binhao Xu
Flying car is a new type of vehicle with high obstacle avoidance ability for urban air traffic and future smart travel. In order to plan feasible paths for flying cars in urban environments, a three dimensional path planning strategy for flying cars based on the fusion of improved A* algorithm and Bezier curves is proposed. Firstly, the search neighborhood of the A* algorithm is improved, and the node expansion is carried out by using the ground mode 9 neighborhood and the low-altitude flight mode 10 neighborhood to quickly obtain feasible path options. Secondly, the energy consumption, time and mode switching loss cost of different motion processes are considered in the heuristic function to achieve unified planning of motion paths and motion modes. Finally, the path is smoothed using piecewise Bezier curves according to the planned path. The results show that in complex maps, compared with traditional vehicles that only consider energy consumption, this strategy effectively reduces the path length by 94.5 m and reduces the weighted cost by 33.1%. Compared with the strategy that comprehensively weighs energy consumption and time, the path length is reduced by 4.31 m and the weighted cost is reduced by 13.6%.
{"title":"Three dimensional path planning for flying car based on improved A* algorithm and Bezier curve fusion","authors":"Jifa Yan, Tao Deng, Binhao Xu","doi":"10.1177/09544070241227094","DOIUrl":"https://doi.org/10.1177/09544070241227094","url":null,"abstract":"Flying car is a new type of vehicle with high obstacle avoidance ability for urban air traffic and future smart travel. In order to plan feasible paths for flying cars in urban environments, a three dimensional path planning strategy for flying cars based on the fusion of improved A* algorithm and Bezier curves is proposed. Firstly, the search neighborhood of the A* algorithm is improved, and the node expansion is carried out by using the ground mode 9 neighborhood and the low-altitude flight mode 10 neighborhood to quickly obtain feasible path options. Secondly, the energy consumption, time and mode switching loss cost of different motion processes are considered in the heuristic function to achieve unified planning of motion paths and motion modes. Finally, the path is smoothed using piecewise Bezier curves according to the planned path. The results show that in complex maps, compared with traditional vehicles that only consider energy consumption, this strategy effectively reduces the path length by 94.5 m and reduces the weighted cost by 33.1%. Compared with the strategy that comprehensively weighs energy consumption and time, the path length is reduced by 4.31 m and the weighted cost is reduced by 13.6%.","PeriodicalId":509770,"journal":{"name":"Proceedings of the Institution of Mechanical Engineers, Part D: Journal of Automobile Engineering","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-01-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140491521","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-01-27DOI: 10.1177/09544070231215846
L. Leng, Jianghua Cheng, Lei Shi, K. Deng
The deterioration of fuel economy for turbocharged engines with altitude is an urgent problem. Turbocompounding is a promising technology to fully recover exhaust energy and reduce engine fuel consumption at off-design altitudes, but it is affected by the environmental boundary caused by altitude. In this study, the effect and mechanism of altitude on the exhaust energy recovery of turbocompound engines were revealed via thermodynamic analysis. The results show that the total system power output of the turbocompound engine is higher than that of the base engine at different altitudes, the maximum improvement percentage of which reaches up to 4.3%; and the total power output deteriorates less with increasing altitude. When the altitude increases to 4 km, the exhaust energy utilization coefficient of turbocompound engine decreases by only about 2%. Based on energy and exergy analysis, full recovery and utilization of exhaust energy contribute to improving the altitude adaptability of turbocharged engines. The maximum altitude while maintaining the engine power constant for the turbocompound engine is 4.66 km under an engine speed of 1800 r/min. Thus, the altitude range over which turbocompound diesel engines can operate efficiently is widened.
{"title":"Thermodynamic analysis on the effect of altitude on the exhaust energy recovery of electric turbocompound engines","authors":"L. Leng, Jianghua Cheng, Lei Shi, K. Deng","doi":"10.1177/09544070231215846","DOIUrl":"https://doi.org/10.1177/09544070231215846","url":null,"abstract":"The deterioration of fuel economy for turbocharged engines with altitude is an urgent problem. Turbocompounding is a promising technology to fully recover exhaust energy and reduce engine fuel consumption at off-design altitudes, but it is affected by the environmental boundary caused by altitude. In this study, the effect and mechanism of altitude on the exhaust energy recovery of turbocompound engines were revealed via thermodynamic analysis. The results show that the total system power output of the turbocompound engine is higher than that of the base engine at different altitudes, the maximum improvement percentage of which reaches up to 4.3%; and the total power output deteriorates less with increasing altitude. When the altitude increases to 4 km, the exhaust energy utilization coefficient of turbocompound engine decreases by only about 2%. Based on energy and exergy analysis, full recovery and utilization of exhaust energy contribute to improving the altitude adaptability of turbocharged engines. The maximum altitude while maintaining the engine power constant for the turbocompound engine is 4.66 km under an engine speed of 1800 r/min. Thus, the altitude range over which turbocompound diesel engines can operate efficiently is widened.","PeriodicalId":509770,"journal":{"name":"Proceedings of the Institution of Mechanical Engineers, Part D: Journal of Automobile Engineering","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-01-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139592893","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-01-27DOI: 10.1177/09544070231217553
Wenzhu Wang, Zhenwei Zhang, Gang Liu, Juntao Wei, Jie Li
In this study a new simulation technology based on fluid-structure coupling is to solve the problem of plastic fuel tank lifting lug fracture during vibration durability test, which has not been reported in the existing literature. The basic principle of fluid-structure coupling is summarised and the finite element model (FEM) of the fuel tank system established. Modal simulation analysis is carried out, and the FEM is updated and verified via the modal test method. A harmonic response analysis of the fuel tank system is performed. Simulation results show the maximum stress at the lifting lug is 29.69 MPa in the Z-direction vibration, exceeding the allowable fatigue strength. The resonance occurred, which is consistent with the result of the vibration durability test. To enable the fuel tank to pass the vibration durability test, this study proposes to optimise the fixture, thereby enhancing the natural frequency of the entire fuel tank system and avoiding an excitation frequency of 30 Hz. Through the harmonic response analysis and test verification, the fuel tank passes the vibration durability test. Therefore, the numerical simulation method based on fluid–structure coupling and the fixture optimisation scheme adopted is feasible and can considerably shorten the test cycle and improve efficiency.
本研究采用了一种基于流固耦合的新型模拟技术，以解决塑料油箱吊耳在振动耐久性试验中断裂的问题，该问题在现有文献中尚未见报道。总结了流固耦合的基本原理，建立了油箱系统的有限元模型（FEM）。进行了模态模拟分析，并通过模态测试方法对有限元模型进行了更新和验证。对油箱系统进行了谐波响应分析。仿真结果表明，在 Z 方向振动中，吊耳处的最大应力为 29.69 兆帕，超过了允许的疲劳强度。共振发生了，这与振动耐久性试验的结果一致。为使油箱通过振动耐久性试验，本研究建议优化夹具，从而提高整个油箱系统的固有频率，避免激振频率达到 30 Hz。通过谐波响应分析和试验验证，油箱通过了振动耐久性试验。因此，基于流固耦合的数值模拟方法和采用的夹具优化方案是可行的，可以大大缩短试验周期，提高试验效率。
{"title":"Simulation study on the vibration durability test of an automotive plastic fuel tank based on fluid–structure coupling","authors":"Wenzhu Wang, Zhenwei Zhang, Gang Liu, Juntao Wei, Jie Li","doi":"10.1177/09544070231217553","DOIUrl":"https://doi.org/10.1177/09544070231217553","url":null,"abstract":"In this study a new simulation technology based on fluid-structure coupling is to solve the problem of plastic fuel tank lifting lug fracture during vibration durability test, which has not been reported in the existing literature. The basic principle of fluid-structure coupling is summarised and the finite element model (FEM) of the fuel tank system established. Modal simulation analysis is carried out, and the FEM is updated and verified via the modal test method. A harmonic response analysis of the fuel tank system is performed. Simulation results show the maximum stress at the lifting lug is 29.69 MPa in the Z-direction vibration, exceeding the allowable fatigue strength. The resonance occurred, which is consistent with the result of the vibration durability test. To enable the fuel tank to pass the vibration durability test, this study proposes to optimise the fixture, thereby enhancing the natural frequency of the entire fuel tank system and avoiding an excitation frequency of 30 Hz. Through the harmonic response analysis and test verification, the fuel tank passes the vibration durability test. Therefore, the numerical simulation method based on fluid–structure coupling and the fixture optimisation scheme adopted is feasible and can considerably shorten the test cycle and improve efficiency.","PeriodicalId":509770,"journal":{"name":"Proceedings of the Institution of Mechanical Engineers, Part D: Journal of Automobile Engineering","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-01-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140492495","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
京公网安备 11010802042870号
京ICP备2023020795号-1
扫码关注我们
求助内容：
应助结果提醒方式：