Lightweight is an effective design strategy to conserve energy in automotive vehicles.It is a big challenge to evaluate the level of lightweight for passenger cars.This paper summarizes various evaluation methods for ...Lightweight is an effective design strategy to conserve energy in automotive vehicles.It is a big challenge to evaluate the level of lightweight for passenger cars.This paper summarizes various evaluation methods for lightweight automotive vehicles.A lightweight index[Lv for internal combustion engine vehicles(ICEVs)and Lev for battery electric vehicles(BEVs)]is proposed to assess the lightweight of passenger cars.The proposed lightweight index is composed of the nominal density,weight-to-power ratio,and fuel consumption of footprint area(in the case of ICEVs)or electricity consumption of footprint area(in the case of BEVs).The validity and universality of the proposed lightweight index are demonstrated through a statis-tical analysis of 7018 ICEV and 326 BEV models.The calculation procedures of the standard partial regression coefficients of statistical multiple regression and elastic coefficients are employed in the proposed method.The results show that either Lv or Lev is most sensitive to the curb mass of the vehicles.The proposed lightweight index can help guide automakers in setting reasonable weight reduction targets during new product development.In addition,the proposed lightweight index can be applied to new hybrid electric vehicles with further efforts,to facilitate the development of lightweight automotive design.展开更多
The significance,description parameters,evaluation method,implement way and design for lightweight of automobile are comprehensively reviewed.The relationship among the performances of auto parts & components,the ...The significance,description parameters,evaluation method,implement way and design for lightweight of automobile are comprehensively reviewed.The relationship among the performances of auto parts & components,the properties of materials and application of advanced technologies is also elaborated.According to recently related progress of lightweight and authors' research and developing work,lightweight of automobile is comprehensively and systematically overviewed.展开更多
The cracking behavior of lightweight aggregate concrete(LWAC) was investigated by mechanical analysis, SEM and cracking-resistant test where a shrinkage-restrained ring with a clapboard was used. The relationship betw...The cracking behavior of lightweight aggregate concrete(LWAC) was investigated by mechanical analysis, SEM and cracking-resistant test where a shrinkage-restrained ring with a clapboard was used. The relationship between the ceramsite type and the cracking resistance of LWAC was built up and compared with that of normal-weight coarse aggregate concrete(NWAC). A new method was proposed to evaluate the cracking resistance of concrete, where the concepts of cracking coefficient ζt(t) and the evaluation index Acr(t) were proposed, and the development of micro-cracks and damage accumulation were recognized. For the concrete with an ascending cracking coefficient curve, the larger Acr(t) is, the lower cracking resistance of concrete is. For the concrete with a descending cracking coefficient curve, the larger Acr(t) is, the stronger the cracking resistance of concrete is. The evaluation results show that in the case of that all the three types of coarse aggregates in concrete are pre-soaked for 24 h, NWAC has the lowest cracking resistance, followed by the LWAC with lower water absorption capacity ceramsite and the LWAC with higher water absorption capacity ceramsite has the strongest cracking resistance. The proposed method has obvious advantages over the cracking age method, because it can evaluate the cracking behavior of concrete even if the concrete has not an observable crack.展开更多
基金This research is funded by National Key Research and Development Program of China(Grant No.2016YFB0101605).
文摘Lightweight is an effective design strategy to conserve energy in automotive vehicles.It is a big challenge to evaluate the level of lightweight for passenger cars.This paper summarizes various evaluation methods for lightweight automotive vehicles.A lightweight index[Lv for internal combustion engine vehicles(ICEVs)and Lev for battery electric vehicles(BEVs)]is proposed to assess the lightweight of passenger cars.The proposed lightweight index is composed of the nominal density,weight-to-power ratio,and fuel consumption of footprint area(in the case of ICEVs)or electricity consumption of footprint area(in the case of BEVs).The validity and universality of the proposed lightweight index are demonstrated through a statis-tical analysis of 7018 ICEV and 326 BEV models.The calculation procedures of the standard partial regression coefficients of statistical multiple regression and elastic coefficients are employed in the proposed method.The results show that either Lv or Lev is most sensitive to the curb mass of the vehicles.The proposed lightweight index can help guide automakers in setting reasonable weight reduction targets during new product development.In addition,the proposed lightweight index can be applied to new hybrid electric vehicles with further efforts,to facilitate the development of lightweight automotive design.
基金International Cooperation Project of Ministry of Science and Technology of China (No.2008DFB50020)
文摘The significance,description parameters,evaluation method,implement way and design for lightweight of automobile are comprehensively reviewed.The relationship among the performances of auto parts & components,the properties of materials and application of advanced technologies is also elaborated.According to recently related progress of lightweight and authors' research and developing work,lightweight of automobile is comprehensively and systematically overviewed.
基金Project(51078090)supported by the National Natural Science Foundation of China
文摘The cracking behavior of lightweight aggregate concrete(LWAC) was investigated by mechanical analysis, SEM and cracking-resistant test where a shrinkage-restrained ring with a clapboard was used. The relationship between the ceramsite type and the cracking resistance of LWAC was built up and compared with that of normal-weight coarse aggregate concrete(NWAC). A new method was proposed to evaluate the cracking resistance of concrete, where the concepts of cracking coefficient ζt(t) and the evaluation index Acr(t) were proposed, and the development of micro-cracks and damage accumulation were recognized. For the concrete with an ascending cracking coefficient curve, the larger Acr(t) is, the lower cracking resistance of concrete is. For the concrete with a descending cracking coefficient curve, the larger Acr(t) is, the stronger the cracking resistance of concrete is. The evaluation results show that in the case of that all the three types of coarse aggregates in concrete are pre-soaked for 24 h, NWAC has the lowest cracking resistance, followed by the LWAC with lower water absorption capacity ceramsite and the LWAC with higher water absorption capacity ceramsite has the strongest cracking resistance. The proposed method has obvious advantages over the cracking age method, because it can evaluate the cracking behavior of concrete even if the concrete has not an observable crack.
