农业工程学报
農業工程學報
농업공정학보
2014年
12期
56-63
,共8页
臧利国%赵又群%李波%王健%杜现斌
臧利國%趙又群%李波%王健%杜現斌
장리국%조우군%리파%왕건%두현빈
车辆%模型%有限元法%机械弹性车轮%非充气轮胎%接地性能
車輛%模型%有限元法%機械彈性車輪%非充氣輪胎%接地性能
차량%모형%유한원법%궤계탄성차륜%비충기륜태%접지성능
vehicles%models%finite element method%mechanical elastic wheel%non-pneumatic tire%contact behavior
为提高轮胎接地性能,对新型机械弹性车轮垂直静态接地特性进行了研究。通过对车轮结构和承载方式进行分析,分别建立了基于Timoshenko圆形梁的车轮外圈弹性圆环模型和基于连续辐板的铰链组模型,并通过非线性有限元法和试验进行了验证。根据所建立的非线性有限元模型对机械弹性车轮和子午线充气轮胎的接地特性进行了对比研究,结果表明机械弹性车轮通过悬毂式承载控制车轮外圈变形,没有胎肩处的应力集中。在载荷为5000 N时,机械弹性车轮和充气轮胎接地印迹中心0.14 m×0.265 m矩形区域内的接地压力偏度值分别为0.424和0.536 MPa。机械弹性车轮有效降低了接地压力偏度值,改善了轮胎接地的均匀性,提高了车轮耐磨损性能和抓地性能,研究为车轮性能优化提供了参考。
為提高輪胎接地性能,對新型機械彈性車輪垂直靜態接地特性進行瞭研究。通過對車輪結構和承載方式進行分析,分彆建立瞭基于Timoshenko圓形樑的車輪外圈彈性圓環模型和基于連續輻闆的鉸鏈組模型,併通過非線性有限元法和試驗進行瞭驗證。根據所建立的非線性有限元模型對機械彈性車輪和子午線充氣輪胎的接地特性進行瞭對比研究,結果錶明機械彈性車輪通過懸轂式承載控製車輪外圈變形,沒有胎肩處的應力集中。在載荷為5000 N時,機械彈性車輪和充氣輪胎接地印跡中心0.14 m×0.265 m矩形區域內的接地壓力偏度值分彆為0.424和0.536 MPa。機械彈性車輪有效降低瞭接地壓力偏度值,改善瞭輪胎接地的均勻性,提高瞭車輪耐磨損性能和抓地性能,研究為車輪性能優化提供瞭參攷。
위제고륜태접지성능,대신형궤계탄성차륜수직정태접지특성진행료연구。통과대차륜결구화승재방식진행분석,분별건립료기우Timoshenko원형량적차륜외권탄성원배모형화기우련속복판적교련조모형,병통과비선성유한원법화시험진행료험증。근거소건립적비선성유한원모형대궤계탄성차륜화자오선충기륜태적접지특성진행료대비연구,결과표명궤계탄성차륜통과현곡식승재공제차륜외권변형,몰유태견처적응력집중。재재하위5000 N시,궤계탄성차륜화충기륜태접지인적중심0.14 m×0.265 m구형구역내적접지압력편도치분별위0.424화0.536 MPa。궤계탄성차륜유효강저료접지압력편도치,개선료륜태접지적균균성,제고료차륜내마손성능화조지성능,연구위차륜성능우화제공료삼고。
A non-pneumatic tire appears to have advantages over the conventional pneumatic tire in terms of flat proof and maintenance free. A mechanical elastic wheel with a non-pneumatic elastic outer ring which functions as the air of the pneumatic tire was presented to reduce the risk of puncturing the conventional pneumatic tire and to enhance the grip performance. The mechanical elastic wheel structure was non-pneumatic integrated configuration which was flat proof and maintenance free of air-pressure. In this study, the static contact behavior of mechanical elastic wheel was investigated as a function of vertical loading and was compared with that of a pneumatic tire. The special suspended hub loaders of mechanical elastic wheel were employed to reduce the contact stiffness and increase contact area so that a stable friction was obtained. An analytical model for a non-pneumatic mechanical elastic wheel on rigid ground is presented. The model consists of a thin flexible annular outer ring and hinge units that connect the outer ring to a rigid hub. According to the wheel structure characteristic and bearing way, outer ring uniformly curved beam model was established based on a circular Timoshenko beam that takes into account deformations due to bending, shearing and circumferential extension, and discrete spoke which was accounted for only in tension was modeled based on continuous spoke model. In addition, the finite element model of mechanical elastic wheel was modeled by using the commercial finite element software ANSYS. To establish the finite element model, various nonlinear factors, such as the geometrical nonlinearity, material nonlinearity and contact nonlinearity, were all considered. In order to proved the validity of the analytical model and the finite element model, load characteristic test of the mechanical elastic wheel was conducted by tyre dynamic test-bed to obtain load-deflection curve. The results of analytical model and three-dimensional nonlinear finite element model were validated by the load characteristic test of mechanical elastic wheel. The trend of tested results were consistent with simulation results and analytical results. The prototype experiment confirmed the analytic model and the finite element model rationality. Finite element methods were used to analyze the contact pressure distribution and grip performance in static loading. Simulation results show that the radial stiffness of mechanical elastic wheel is greater than that of pneumatic tire, so that mechanical elastic wheel could maintain more better roundness and lesser rolling resistance than pneumatic tire. Through mechanic analysis, it shows that radial stiffness of mechanical elastic wheel is determined by stiffness of elastic outer ring, stiffness of hinges and the suspended hub loaders. Besides that, simulation results also show that the static contact pressure of mechanical elastic wheel on tire shoulder becomes protuberant with the increase of the vertical load, and the static contact pressure of mechanical elastic wheel is more evenly than that of traditional pneumatic tire. That is because the suspended hub loaders could reduce the stress concentration of tire shoulder and enhance tire wear resistance and grip performance by controlling outer ring deformation. The results can provide guidance for experiment research, structural optimization and improvements of vehicle dynamics.