车轮-地面耦合动力学行为的CDEM-DEM分析  

CDEM-DEM analysis of the coupled wheel-ground dynamics behavior

作　　者：路扬 冯春[2,3] 程鹏达 张一鸣 LU Yang;FENG Chun;CHENG Pengda;ZHANG Yiming(School of Civil and Transportation Engineering,Hebei University of Technology,Tianjin 300401,China;Institute of Mechanics,Chinese Academy of Sciences,Beijing 100190,China;School of Engineering Sciences,University of Chinese Academy of Sciences,Beijing 100049,China)

机构地区：[1]河北工业大学、土木与交通学院,天津300401 [2]中国科学院、力学研究所,北京100190 [3]中国科学院大学、工程科学学院,北京100049

出　　处：《光学精密工程》2023年第5期746-756,共11页Optics and Precision Engineering

基　　金：钱学森实验室太空探索实验培育项目(No.TKTSPY-2020-05-01);国家自然科学基金项目(No.52178324)。

摘　　要：越野车辆在软土路面上行驶时,其车轮-地面相互作用的动态力学行为极其复杂,车轮的下陷程度和通行能力均为车辆地面力学研究的重点。为探究车轮在软土路面通行时的动力学性能,本文提出了一种连续-非连续单元法(Continu⁃ous-discontinuous Element Method,CDEM)与颗粒离散元法(Discrete Element Method,DEM)相结合的耦合计算方法。该方法中,车轮采用CDEM单元进行描述,软土路面采用DEM颗粒进行描述,CDEM单元与DEM颗粒之间采用罚弹簧进行耦合,通过在车轮上施加动态扭矩,实现了车轮在软土路面上摩擦、滚动及前行过程的精确模拟。借助CDEM与DEM的耦合,探讨了车轮花纹、路障对车辆行驶过程中动力学行为的影响规律。研究结果表明:花纹车轮及光面车轮均在软土路面留下清晰可见的车辙;花纹轮胎较光面轮胎表现出更强的通行能力;花纹车轮转动速度较小,但其车轮平动速度远高于光面车轮,花纹车轮平动与其线速度之比约为12.78%,而光面车轮比值仅为2.80%;车轮在软土路面行驶过程中,相同质量下的光面车轮下陷深度远高于花纹车轮;车辆在含路障路面通行时,地面起伏度与车辆行驶能耗之间密切相关,起伏度越大,所需能量越大。The dynamic mechanical wheel-ground interaction is extremely complex when off-road vehicles are driven on soft soil pavements,and the extent of wheel sagging and traversability are of significant interest in the field of vehicle ground mechanics.This study proposes a calculation approach that uses the continuum-discontinuum element method(CDEM)and discrete element method(DEM)in combination to analyze the dynamic performance of wheels on soft-soil pavements.In the proposed method,the wheel is modeled using CDEM elements,the soft-soil pavement is modeled using DEM particles,and a penalty spring is used to connect both models.The application of dynamic torque to the wheel allows for the accurate simulation of the friction,rolling,and forward motion of the wheel on the soft-soil pavement.By combining CDEM and DEM,the study explores the effect of wheel patterns and roadblocks on the dynamic behavior of the vehicle during driving.The results show that both patterned and glossy wheels leave visible ruts on the soft-soil road surface,with patterned tires having better traversability than glossy ones.The rotation speed of patterned wheels is slower,but their translation speed is much faster than that of glossy wheels,with a translation-to-linear speed ratio of 12.78%for patterned wheels and 2.80%for glossy wheels.During driving on soft-soil roads,glossy wheels sink deeper into the ground compared to patterned wheels with the same weight.Furthermore,when driving over roadblocks,the degree of ground undulation has a direct impact on vehicle energy consumption,with greater undulation requiring more energy.

关 键 词：车轮下陷 软土路面 CDEM DEM 数值模拟 

分 类 号：U461.5[机械工程—车辆工程]