Pub Date : 2024-07-27DOI: 10.1177/09544070241265024
Qinghua Li, Chunyu Wang, Kai Xiao, Chun-Yang Ma, Shihong Zhang
This paper combines the processing of composite synchronizer ring and carbon fiber cloth pre-preg process to study the friction mechanism after adding filler in carbon fiber cloth of composite synchronizer ring, so as to improve the friction and wear performance of composite synchronizer ring. In order to increase the friction factor and thermal stability of composite synchronizer ring friction material two ways as an entry point, select the friction reducing filler in the good thermal conductivity of copper powder and friction increasing filler in the barite as the experimental filler in this paper. The results show that the friction temperature of the composite synchronizer ring without filler is higher and the wear is bigger, the composite synchronizer ring with barite as the filler is second, and the composite synchronizer ring with copper powder as the filler has the best effect of temperature reduction and wear reduction. In the shift force of 400 N, speed difference of 350 r/min, experimental time of 250 min conditions, adding copper powder to reduce the wear volume of about 10%, the friction coefficient is more stable average value decreased by about 0.02, only reduced by about 5%, which is better than the barite as a filler of 0.045; and from the surface quality of the composite synchronizer ring with copper powder as a filler the surface texture is clear. Still has a good oil storage and drainage capacity, can effectively improve the composite synchronizer ring wear resistance and service life. Barite as filler composite synchronizer ring initial friction coefficient is slightly higher, but the coefficient of friction decreased by about 20%, the composite synchronizer ring scratches and local carbon fiber shedding phenomenon, resulting in irreversible performance degradation.
{"title":"Influence of filler-reinforced carbon fibers on the frictional properties of composite synchronizer rings","authors":"Qinghua Li, Chunyu Wang, Kai Xiao, Chun-Yang Ma, Shihong Zhang","doi":"10.1177/09544070241265024","DOIUrl":"https://doi.org/10.1177/09544070241265024","url":null,"abstract":"This paper combines the processing of composite synchronizer ring and carbon fiber cloth pre-preg process to study the friction mechanism after adding filler in carbon fiber cloth of composite synchronizer ring, so as to improve the friction and wear performance of composite synchronizer ring. In order to increase the friction factor and thermal stability of composite synchronizer ring friction material two ways as an entry point, select the friction reducing filler in the good thermal conductivity of copper powder and friction increasing filler in the barite as the experimental filler in this paper. The results show that the friction temperature of the composite synchronizer ring without filler is higher and the wear is bigger, the composite synchronizer ring with barite as the filler is second, and the composite synchronizer ring with copper powder as the filler has the best effect of temperature reduction and wear reduction. In the shift force of 400 N, speed difference of 350 r/min, experimental time of 250 min conditions, adding copper powder to reduce the wear volume of about 10%, the friction coefficient is more stable average value decreased by about 0.02, only reduced by about 5%, which is better than the barite as a filler of 0.045; and from the surface quality of the composite synchronizer ring with copper powder as a filler the surface texture is clear. Still has a good oil storage and drainage capacity, can effectively improve the composite synchronizer ring wear resistance and service life. Barite as filler composite synchronizer ring initial friction coefficient is slightly higher, but the coefficient of friction decreased by about 20%, the composite synchronizer ring scratches and local carbon fiber shedding phenomenon, resulting in irreversible performance degradation.","PeriodicalId":509770,"journal":{"name":"Proceedings of the Institution of Mechanical Engineers, Part D: Journal of Automobile Engineering","volume":"4 9","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-07-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141797477","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}
The electro-hydraulic composite steering system can reduce steering energy consumption through cooperative control of electro-hydraulic mechanisms, an inevitable trend for global commercial vehicles and green logistics. However, in cooperative control, the electro-hydraulic coupling characteristics not only lead to an increase in system energy consumption but also cause fluctuations in system speed during electro-hydraulic switching. In response to the above issues, this paper proposes a long-short-time domain steering mode selection and torque optimal allocation strategy that integrates long-time domain steering mode selection and short-time domain torque allocation. In the long-term domain, with steering energy consumption as the optimization indicator, the optimal steering mode is selected through a steering mode selection model based on the CNN-LSTM network to reduce steering energy consumption. In the short time domain, the Holt Winter exponential smoothing and support vector regression methods are combined for torque prediction, and the steering energy consumption and electro-hydraulic switching smoothness indicators are comprehensively considered. The electro-hydraulic torque distribution ratio is dynamically optimized in the rolling time domain to reduce the fluctuation of hydraulic pump speed during electro-hydraulic switching. The simulation and experimental results show that the proposed method can improve the switching smoothness of the electro-hydraulic composite steering system and reduce the system’s overall energy consumption by 54.1%.
{"title":"Long-short-time domain torque optimal prediction and allocation method for electric logistics vehicles with electro-hydraulic composite steering system","authors":"Weihe Liang, Wanzhong Zhao, Chunyan Wang, Zhongkai Luan","doi":"10.1177/09544070241265633","DOIUrl":"https://doi.org/10.1177/09544070241265633","url":null,"abstract":"The electro-hydraulic composite steering system can reduce steering energy consumption through cooperative control of electro-hydraulic mechanisms, an inevitable trend for global commercial vehicles and green logistics. However, in cooperative control, the electro-hydraulic coupling characteristics not only lead to an increase in system energy consumption but also cause fluctuations in system speed during electro-hydraulic switching. In response to the above issues, this paper proposes a long-short-time domain steering mode selection and torque optimal allocation strategy that integrates long-time domain steering mode selection and short-time domain torque allocation. In the long-term domain, with steering energy consumption as the optimization indicator, the optimal steering mode is selected through a steering mode selection model based on the CNN-LSTM network to reduce steering energy consumption. In the short time domain, the Holt Winter exponential smoothing and support vector regression methods are combined for torque prediction, and the steering energy consumption and electro-hydraulic switching smoothness indicators are comprehensively considered. The electro-hydraulic torque distribution ratio is dynamically optimized in the rolling time domain to reduce the fluctuation of hydraulic pump speed during electro-hydraulic switching. The simulation and experimental results show that the proposed method can improve the switching smoothness of the electro-hydraulic composite steering system and reduce the system’s overall energy consumption by 54.1%.","PeriodicalId":509770,"journal":{"name":"Proceedings of the Institution of Mechanical Engineers, Part D: Journal of Automobile Engineering","volume":"86 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-07-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141798461","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 : 2024-07-27DOI: 10.1177/09544070241264596
Yan Chen, Liang Su, Yong Zhang, Feng Zhang, G. Gong
Amidst the advancements in autonomous driving technology, platoons composed of autonomous vehicles have garnered significant attention due to their potential to alleviate traffic congestion and enhance transportation capacity. Addressing the issue of slow-moving vehicles obstructing the roadway, this study introduces a consistent overtaking strategy, leveraging an improved artificial potential field (IAPF) method. Through the incorporation of a velocity repulsive force field, a refined obstacle position repulsive force field, and a road boundary repulsive force field, the cumulative resultant force vector experienced by the autonomous vehicle is treated holistically. This approach ensures that the vehicle traverses in the direction of the total resultant force unit vector at a predefined speed. Moreover, the repulsive and attractive force coefficients are determined to guarantee convoy safety and uniform velocity. This research sets forth the architecture of the autonomous vehicle platoon, reconceptualizing overtaking maneuvers as dynamic target-tracking challenges. Throughout the overtaking phase, the obstructive vehicle is chosen either based on specific criteria fulfillment or by designating the lead vehicle's speed to a virtual dynamic target, thus safeguarding the overtaking procedure against potential collisions. Comprehensive simulations, conducted using Matlab and Unreal Engine software platforms, corroborate the efficacy and viability of the IAPF-based consistent speed overtaking strategy. Relative to the conventional APF approach, this method facilitates safe obstacle circumvention in dynamic settings and ensures vehicle velocity remains unaffected by resultant force fluctuations, maintaining consistent speed during overtaking.
{"title":"Autonomous vehicle platoon overtaking at a uniform speed based on improved artificial potential field method","authors":"Yan Chen, Liang Su, Yong Zhang, Feng Zhang, G. Gong","doi":"10.1177/09544070241264596","DOIUrl":"https://doi.org/10.1177/09544070241264596","url":null,"abstract":"Amidst the advancements in autonomous driving technology, platoons composed of autonomous vehicles have garnered significant attention due to their potential to alleviate traffic congestion and enhance transportation capacity. Addressing the issue of slow-moving vehicles obstructing the roadway, this study introduces a consistent overtaking strategy, leveraging an improved artificial potential field (IAPF) method. Through the incorporation of a velocity repulsive force field, a refined obstacle position repulsive force field, and a road boundary repulsive force field, the cumulative resultant force vector experienced by the autonomous vehicle is treated holistically. This approach ensures that the vehicle traverses in the direction of the total resultant force unit vector at a predefined speed. Moreover, the repulsive and attractive force coefficients are determined to guarantee convoy safety and uniform velocity. This research sets forth the architecture of the autonomous vehicle platoon, reconceptualizing overtaking maneuvers as dynamic target-tracking challenges. Throughout the overtaking phase, the obstructive vehicle is chosen either based on specific criteria fulfillment or by designating the lead vehicle's speed to a virtual dynamic target, thus safeguarding the overtaking procedure against potential collisions. Comprehensive simulations, conducted using Matlab and Unreal Engine software platforms, corroborate the efficacy and viability of the IAPF-based consistent speed overtaking strategy. Relative to the conventional APF approach, this method facilitates safe obstacle circumvention in dynamic settings and ensures vehicle velocity remains unaffected by resultant force fluctuations, maintaining consistent speed during overtaking.","PeriodicalId":509770,"journal":{"name":"Proceedings of the Institution of Mechanical Engineers, Part D: Journal of Automobile Engineering","volume":"75 24","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-07-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141798471","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 : 2024-07-26DOI: 10.1177/09544070241261657
Samaneh Soltanalizadeh, Mohammad Reza Haeri Yazdi, Vahid Esfahanian, Mohammad Nejat
Strict environmental laws increase the importance of reducing emissions. While; improving three-way catalyst (TWC) technology can help reduce emission levels, attention should also be given to reducing exhaust gases before they enter the TWC. This can be achieved through the development of engine technology and calibration strategies. By doing so, low-cost TWC can be used, and emissions increase less after catalyst aging. In addition to reducing emissions at the engine-out stage before entering the TWC, it is important to reduce emissions after the TWC during the cold start and engine warm-up phase, known as the TWC light-off period. During this stage, the TWC does not reach optimal working efficiency, which can result in higher emissions. Therefore, to comply with environmental regulations, it is necessary to calculate the reduction of emissions while maintaining optimal engine and vehicle performance. Finding the optimal values of control parameters to reduce fuel consumption and emissions simultaneously makes engine calibration a complex multi-objective optimization problem. To meet calibration requirements, it is essential to accurately identify the nonlinear and multivariable behavior of engines. Thus, this study focuses on empirical engine modeling and developing an emissions model for internal combustion engines in both warm and cold engine conditions through an intelligent identification method. To enhance steady state engine modeling in warm conditions, this study proposes a hybrid MLP+CNN method based on the benefits of regression deep neural network. Additionally, the hybrid MLP+CNN+LSTM method adds a long short-term memory (LSTM) neural network, enabling the model to capture the dynamic behavior of emissions during cold start conditions and under the impact of oxygen storage and the temperature in TWC. The results demonstrate that these approaches significantly improve the accuracy of emission modeling when compared to conventional methods. The results demonstrate that using the deep learning approach and dividing the engine emission modeling into two parts, static in warm conditions and dynamic in cold conditions, significantly improve the accuracy of emission modeling compared to conventional methods. Developed models can be used in the model-based calibration due to their high accuracy in emission prediction as well as predicting Torque, BSFC, and other outputs. By coupling the developed model with optimization techniques, calibration of the engine map and cold start can be performed by considering the emissions, torque, etc., simultaneously.
{"title":"Prediction of emission and performance of internal combustion engine via regression deep learning approach","authors":"Samaneh Soltanalizadeh, Mohammad Reza Haeri Yazdi, Vahid Esfahanian, Mohammad Nejat","doi":"10.1177/09544070241261657","DOIUrl":"https://doi.org/10.1177/09544070241261657","url":null,"abstract":"Strict environmental laws increase the importance of reducing emissions. While; improving three-way catalyst (TWC) technology can help reduce emission levels, attention should also be given to reducing exhaust gases before they enter the TWC. This can be achieved through the development of engine technology and calibration strategies. By doing so, low-cost TWC can be used, and emissions increase less after catalyst aging. In addition to reducing emissions at the engine-out stage before entering the TWC, it is important to reduce emissions after the TWC during the cold start and engine warm-up phase, known as the TWC light-off period. During this stage, the TWC does not reach optimal working efficiency, which can result in higher emissions. Therefore, to comply with environmental regulations, it is necessary to calculate the reduction of emissions while maintaining optimal engine and vehicle performance. Finding the optimal values of control parameters to reduce fuel consumption and emissions simultaneously makes engine calibration a complex multi-objective optimization problem. To meet calibration requirements, it is essential to accurately identify the nonlinear and multivariable behavior of engines. Thus, this study focuses on empirical engine modeling and developing an emissions model for internal combustion engines in both warm and cold engine conditions through an intelligent identification method. To enhance steady state engine modeling in warm conditions, this study proposes a hybrid MLP+CNN method based on the benefits of regression deep neural network. Additionally, the hybrid MLP+CNN+LSTM method adds a long short-term memory (LSTM) neural network, enabling the model to capture the dynamic behavior of emissions during cold start conditions and under the impact of oxygen storage and the temperature in TWC. The results demonstrate that these approaches significantly improve the accuracy of emission modeling when compared to conventional methods. The results demonstrate that using the deep learning approach and dividing the engine emission modeling into two parts, static in warm conditions and dynamic in cold conditions, significantly improve the accuracy of emission modeling compared to conventional methods. Developed models can be used in the model-based calibration due to their high accuracy in emission prediction as well as predicting Torque, BSFC, and other outputs. By coupling the developed model with optimization techniques, calibration of the engine map and cold start can be performed by considering the emissions, torque, etc., simultaneously.","PeriodicalId":509770,"journal":{"name":"Proceedings of the Institution of Mechanical Engineers, Part D: Journal of Automobile Engineering","volume":"33 35","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-07-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141800506","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 : 2024-06-10DOI: 10.1177/09544070241254421
T. S. Balaram, K. Muralidharan, Ugs Akhilesh, N. Pranav, P. Akash, R. Vignesh, R. Senthilkumar, A. Saiyathibrahim, Indran Suyambulingam, S. Siengchin
In this study, the formulation of nano lubricants is undertaken through the utilization of SAE20W40 engine oil and surface-activated praseodymium oxide (Pr6O11). An analysis is conducted on the impact of concentration profile (0.1, 0.3, 0.5 wt.%) on various physio-chemical properties, including stability, viscosity, fire and flash point, calorific value, acid value, and iodine value of the nano lubricants. The wear rate and coefficient of friction are determined through the utilization of a pin-on-disc tribometer for all the synthesized nano lubricants. A comprehensive examination on the attributes of the synthesized nano lubricants is presented by means of informative images and graphs obtained from SEM, EDS, TEM, FT-IR, UV-Vis, and DSC. It is revealed that the lubricant oil containing 0.3 wt.% of Pr6O11 demonstrates superior performance when compared to the base lubricant.
{"title":"Influence of surface activated nanophase Pr6O11 particles on the physio-chemical and tribological characteristics of SAE20W40 automotive lubricant","authors":"T. S. Balaram, K. Muralidharan, Ugs Akhilesh, N. Pranav, P. Akash, R. Vignesh, R. Senthilkumar, A. Saiyathibrahim, Indran Suyambulingam, S. Siengchin","doi":"10.1177/09544070241254421","DOIUrl":"https://doi.org/10.1177/09544070241254421","url":null,"abstract":"In this study, the formulation of nano lubricants is undertaken through the utilization of SAE20W40 engine oil and surface-activated praseodymium oxide (Pr6O11). An analysis is conducted on the impact of concentration profile (0.1, 0.3, 0.5 wt.%) on various physio-chemical properties, including stability, viscosity, fire and flash point, calorific value, acid value, and iodine value of the nano lubricants. The wear rate and coefficient of friction are determined through the utilization of a pin-on-disc tribometer for all the synthesized nano lubricants. A comprehensive examination on the attributes of the synthesized nano lubricants is presented by means of informative images and graphs obtained from SEM, EDS, TEM, FT-IR, UV-Vis, and DSC. It is revealed that the lubricant oil containing 0.3 wt.% of Pr6O11 demonstrates superior performance when compared to the base lubricant.","PeriodicalId":509770,"journal":{"name":"Proceedings of the Institution of Mechanical Engineers, Part D: Journal of Automobile Engineering","volume":" 13","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-06-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141366659","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 : 2024-06-07DOI: 10.1177/09544070241252226
Xinling Zhang, Hanxue Cao, Bin Jiang, Muchen Ma
The amount of knee room provided for a driver is thoroughly considered during automobile design. An inappropriate design affects not only the driver’s comfort but also the frontal impact score. However, at present, the design standard for a driver’s knee room for the people of China is still lacking, which makes it difficult for engineers to prevent associated problems and can even seriously affect drivers’ comfort. By focusing on the driving postures of the people of China in passenger cars, the spatial curves of drivers’ knee rooms suitable for 95th, 50th and 5th percentiles of the Chinese population are investigated in this study based on polynomial machine learning algorithms. The curves change during driving and are stretched into surfaces, which are known as the limit surfaces of the knee room, to limit the component design around the knee, thereby improving the driver’s comfort. The limit surfaces of the knee rooms studied in this article fill the gap in the non-standardized design of knee rooms for passenger vehicles and are highly valuable in commerce.
{"title":"Knee room suggestions for passenger vehicles based on Chinese body measurements and knee point polynomial curves","authors":"Xinling Zhang, Hanxue Cao, Bin Jiang, Muchen Ma","doi":"10.1177/09544070241252226","DOIUrl":"https://doi.org/10.1177/09544070241252226","url":null,"abstract":"The amount of knee room provided for a driver is thoroughly considered during automobile design. An inappropriate design affects not only the driver’s comfort but also the frontal impact score. However, at present, the design standard for a driver’s knee room for the people of China is still lacking, which makes it difficult for engineers to prevent associated problems and can even seriously affect drivers’ comfort. By focusing on the driving postures of the people of China in passenger cars, the spatial curves of drivers’ knee rooms suitable for 95th, 50th and 5th percentiles of the Chinese population are investigated in this study based on polynomial machine learning algorithms. The curves change during driving and are stretched into surfaces, which are known as the limit surfaces of the knee room, to limit the component design around the knee, thereby improving the driver’s comfort. The limit surfaces of the knee rooms studied in this article fill the gap in the non-standardized design of knee rooms for passenger vehicles and are highly valuable in commerce.","PeriodicalId":509770,"journal":{"name":"Proceedings of the Institution of Mechanical Engineers, Part D: Journal of Automobile Engineering","volume":" 2","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-06-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141371437","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 : 2024-06-07DOI: 10.1177/09544070241254598
Zhengfeng Yan, Hongfei Nie, Shaofei Liu, Bo Zhang, Guanhua Tan
Vehicle ride comfort is significantly influenced by powertrain torsional vibration. A multi-condition and multi-index evaluation method of the torsional vibration of the powertrain is proposed in this paper, which selects different evaluation indices according to the characteristics of different working conditions. First, the torsional vibration excitation source of the powertrain is analyzed. The selected indices are the speed amplitude value obtained with the root mean square value, the vibration dose value, the peak-to-peak value, the vibration isolation rate ([Formula: see text]), and the speed fluctuation attenuation rate ([Formula: see text]). Second, the torsional vibration characteristics of ignition, idle, startup, acceleration, deceleration, and switching from tip-in to tip-out are analyzed, and the torsional vibration evaluation indices of each working condition are determined. Then the torsional characteristics of a dual-mass flywheel (DMF) are tested before and after optimization, and the vehicle is tested according to the selected working conditions. Finally, by removing the trend term in the extracted data, the speed amplitude is obtained to calculate the evaluation indices for each working condition. The test results show that the damping performance is improved after the optimization of the DMF, and the evaluation indices under different working conditions are improved by approximately 7% in general, the magnitude of the indices under each working condition showed the same trend, which verifies the feasibility of the evaluation for the multi-condition and multi-index methods and provides references for evaluating the torsional vibration of the powertrain.
{"title":"Experimental evaluation of the torsional vibration characteristics of a dual-mass flywheel based on multi-condition and multi-index methods","authors":"Zhengfeng Yan, Hongfei Nie, Shaofei Liu, Bo Zhang, Guanhua Tan","doi":"10.1177/09544070241254598","DOIUrl":"https://doi.org/10.1177/09544070241254598","url":null,"abstract":"Vehicle ride comfort is significantly influenced by powertrain torsional vibration. A multi-condition and multi-index evaluation method of the torsional vibration of the powertrain is proposed in this paper, which selects different evaluation indices according to the characteristics of different working conditions. First, the torsional vibration excitation source of the powertrain is analyzed. The selected indices are the speed amplitude value obtained with the root mean square value, the vibration dose value, the peak-to-peak value, the vibration isolation rate ([Formula: see text]), and the speed fluctuation attenuation rate ([Formula: see text]). Second, the torsional vibration characteristics of ignition, idle, startup, acceleration, deceleration, and switching from tip-in to tip-out are analyzed, and the torsional vibration evaluation indices of each working condition are determined. Then the torsional characteristics of a dual-mass flywheel (DMF) are tested before and after optimization, and the vehicle is tested according to the selected working conditions. Finally, by removing the trend term in the extracted data, the speed amplitude is obtained to calculate the evaluation indices for each working condition. The test results show that the damping performance is improved after the optimization of the DMF, and the evaluation indices under different working conditions are improved by approximately 7% in general, the magnitude of the indices under each working condition showed the same trend, which verifies the feasibility of the evaluation for the multi-condition and multi-index methods and provides references for evaluating the torsional vibration of the powertrain.","PeriodicalId":509770,"journal":{"name":"Proceedings of the Institution of Mechanical Engineers, Part D: Journal of Automobile Engineering","volume":" 34","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-06-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141374270","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 : 2024-06-07DOI: 10.1177/09544070241254424
Guangyuan Bao, He Chao, Jiaqiang Li, Xueyuan Liu
In order to control gas stratification in diesel engine cylinders and achieve stratified combustion, an experimental and computational fluid dynamics (CFD) coupled approach was employed. The intake section of the helical intake port was divided into four independent intake zones with equal areas by clockwise division: the upper right zone A, upper left zone B, lower left zone C, and lower right zone D. Each zone was supplied with a tracer gas to study the influence of key structural elements of the helical port on gas stratification characteristics within the cylinder. The results indicate that zone D had the highest intake mass, accounting for 27.3% of the total intake, while zone B had the lowest intake mass at 22.4%. In the combustion chamber, intake from zones A and B formed an upper-rich, lower-lean distribution pattern, while intake from zone C formed an upper-lean, lower-rich distribution pattern. The stratification concentration gradient might be quantitatively described thanks to the application of “density ratio.” Lift increased by 5.6% at a 15° intake port deflection angle because the combustion chamber’s maximum axial density ratio was 0.186 and its maximum swirl ratio was 3.57. Soot generation fell by 12.9% under axial stratification, although NOX generation increased by 4.9%.
为了控制柴油发动机气缸内的气体分层并实现分层燃烧,采用了实验和计算流体动力学(CFD)耦合方法。将螺旋进气口的进气部分按顺时针方向划分为四个面积相等的独立进气区:右上区 A、左上区 B、左下区 C 和右下区 D。结果表明,D 区的进气量最大,占总进气量的 27.3%,而 B 区的进气量最小,占 22.4%。在燃烧室中,来自 A 区和 B 区的进气量形成了上富下贫的分布格局,而来自 C 区的进气量则形成了上贫下富的分布格局。由于采用了 "密度比",可以对分层浓度梯度进行定量描述。由于燃烧室的最大轴向密度比为 0.186,最大漩涡比为 3.57,因此在进气口偏转角为 15° 时,升力增加了 5.6%。在轴向分层条件下,烟尘生成量减少了 12.9%,但氮氧化物生成量增加了 4.9%。
{"title":"Influence of key structure of diesel engine helical intake port on intake stratification","authors":"Guangyuan Bao, He Chao, Jiaqiang Li, Xueyuan Liu","doi":"10.1177/09544070241254424","DOIUrl":"https://doi.org/10.1177/09544070241254424","url":null,"abstract":"In order to control gas stratification in diesel engine cylinders and achieve stratified combustion, an experimental and computational fluid dynamics (CFD) coupled approach was employed. The intake section of the helical intake port was divided into four independent intake zones with equal areas by clockwise division: the upper right zone A, upper left zone B, lower left zone C, and lower right zone D. Each zone was supplied with a tracer gas to study the influence of key structural elements of the helical port on gas stratification characteristics within the cylinder. The results indicate that zone D had the highest intake mass, accounting for 27.3% of the total intake, while zone B had the lowest intake mass at 22.4%. In the combustion chamber, intake from zones A and B formed an upper-rich, lower-lean distribution pattern, while intake from zone C formed an upper-lean, lower-rich distribution pattern. The stratification concentration gradient might be quantitatively described thanks to the application of “density ratio.” Lift increased by 5.6% at a 15° intake port deflection angle because the combustion chamber’s maximum axial density ratio was 0.186 and its maximum swirl ratio was 3.57. Soot generation fell by 12.9% under axial stratification, although NOX generation increased by 4.9%.","PeriodicalId":509770,"journal":{"name":"Proceedings of the Institution of Mechanical Engineers, Part D: Journal of Automobile Engineering","volume":" 40","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-06-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141373503","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 : 2024-06-07DOI: 10.1177/09544070241254608
Tao Qiu, Huihui Chen, Yan Lei, Ying Wang, Ao Zhang
High-pressure gas fuel direct injection (HPDI) technology benefits the engine with high efficiency and great output power. During the initial ignition process of the gas fuel jet ignited by the pre-ignition flame, the gas jet interacts with the pre-ignition flame, and causes important effects on the flame propagation and stability. This work aims to investigate the effects of the high-pressure gas fuel (methane) jet on the premixed methane flame with an equivalence ratio of 0.7 in a constant volume bomb (CVB) based on a three-dimensional numerical model. The results indicate that there is a complex interaction between the high-pressure methane jet and the premixed flame. The dominant combustion mode within the CVB changes from the premixed flame surface to the diffusion flame surface, which results in two different combustion behaviors in different regions along the methane jet direction, that is, primary ignition and secondary ignition. The methane jet flame development is divided into three regions, that is, laminar combustion laminar-turbulent combustion, turbulent combustion. Reynolds number of the main region of turbulent combustion ranges within Re = 2300–6000, which means that this flame is a small-scale turbulent flame. These findings contribute to understanding the combustion characteristics under high-pressure direct injection natural gas engine conditions, particularly in lean burn conditions, providing valuable insights for natural gas lean-burn flame stability.
高压气体燃料直喷(HPDI)技术使发动机效率高、输出功率大。在预点火火焰点燃气体燃料射流的初始点火过程中,气体射流与预点火火焰相互作用,对火焰的传播和稳定性产生重要影响。这项工作旨在基于三维数值模型,研究高压气体燃料(甲烷)射流对等效比为 0.7 的恒定体积炸弹(CVB)中预混合甲烷火焰的影响。结果表明,高压甲烷射流与预混合火焰之间存在复杂的相互作用。CVB 内的主导燃烧模式由预混合火焰面转变为扩散火焰面,从而在甲烷射流方向的不同区域产生了两种不同的燃烧行为,即一次点火和二次点火。甲烷喷射火焰的发展分为三个区域,即层流燃烧、层流-湍流燃烧、湍流燃烧。湍流燃烧主要区域的雷诺数在 Re = 2300-6000 范围内,这意味着该火焰属于小尺度湍流火焰。这些发现有助于理解高压直喷天然气发动机工况下的燃烧特性,尤其是贫燃工况下的燃烧特性,为天然气贫燃火焰的稳定性提供了有价值的见解。
{"title":"Study on the effect of high-pressure methane jet on lean burn laminar flame","authors":"Tao Qiu, Huihui Chen, Yan Lei, Ying Wang, Ao Zhang","doi":"10.1177/09544070241254608","DOIUrl":"https://doi.org/10.1177/09544070241254608","url":null,"abstract":"High-pressure gas fuel direct injection (HPDI) technology benefits the engine with high efficiency and great output power. During the initial ignition process of the gas fuel jet ignited by the pre-ignition flame, the gas jet interacts with the pre-ignition flame, and causes important effects on the flame propagation and stability. This work aims to investigate the effects of the high-pressure gas fuel (methane) jet on the premixed methane flame with an equivalence ratio of 0.7 in a constant volume bomb (CVB) based on a three-dimensional numerical model. The results indicate that there is a complex interaction between the high-pressure methane jet and the premixed flame. The dominant combustion mode within the CVB changes from the premixed flame surface to the diffusion flame surface, which results in two different combustion behaviors in different regions along the methane jet direction, that is, primary ignition and secondary ignition. The methane jet flame development is divided into three regions, that is, laminar combustion laminar-turbulent combustion, turbulent combustion. Reynolds number of the main region of turbulent combustion ranges within Re = 2300–6000, which means that this flame is a small-scale turbulent flame. These findings contribute to understanding the combustion characteristics under high-pressure direct injection natural gas engine conditions, particularly in lean burn conditions, providing valuable insights for natural gas lean-burn flame stability.","PeriodicalId":509770,"journal":{"name":"Proceedings of the Institution of Mechanical Engineers, Part D: Journal of Automobile Engineering","volume":" 3","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-06-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141375006","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 : 2024-06-07DOI: 10.1177/09544070241252886
Xiaotian Shi, He Li, Ke Fu
In the application of magnetorheological (MR) semi-active suspensions, the target damping force calculated using the controller must be realised by an MR damper. This requires the target damping force first to be converted into a corresponding drive current. However, owing to the nonlinearity of MR dampers, the drive current based on the target damping force cannot be accurately tracked, which could worsen the control performance. To avoid this situation, this study proposed a gain scheduling control method based on a linear parameter-varying (LPV) model of MR semi-active suspensions. First, based on the nonlinear model of MR semi-active suspension, an LPV model with constraints used as varying parameters was established using convex decomposition. Then, an LPV controller was designed with a convex polytope structure using the linear matrix inequality technique. A system with this controller can achieve H∞ performance. The simulation results showed that the drive current directly obtained with the LPV controller can better utilise the effective region of the MR damper. Consequently, this controller yields smoother current control quantities and lower computational costs while guaranteeing the performance.
{"title":"Design of a direct current controller for magnetorheological semi-active suspensions with nonlinear constraints","authors":"Xiaotian Shi, He Li, Ke Fu","doi":"10.1177/09544070241252886","DOIUrl":"https://doi.org/10.1177/09544070241252886","url":null,"abstract":"In the application of magnetorheological (MR) semi-active suspensions, the target damping force calculated using the controller must be realised by an MR damper. This requires the target damping force first to be converted into a corresponding drive current. However, owing to the nonlinearity of MR dampers, the drive current based on the target damping force cannot be accurately tracked, which could worsen the control performance. To avoid this situation, this study proposed a gain scheduling control method based on a linear parameter-varying (LPV) model of MR semi-active suspensions. First, based on the nonlinear model of MR semi-active suspension, an LPV model with constraints used as varying parameters was established using convex decomposition. Then, an LPV controller was designed with a convex polytope structure using the linear matrix inequality technique. A system with this controller can achieve H∞ performance. The simulation results showed that the drive current directly obtained with the LPV controller can better utilise the effective region of the MR damper. Consequently, this controller yields smoother current control quantities and lower computational costs while guaranteeing the performance.","PeriodicalId":509770,"journal":{"name":"Proceedings of the Institution of Mechanical Engineers, Part D: Journal of Automobile Engineering","volume":" 4","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-06-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141372106","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}