八轴连通式油气悬架车辆行驶性能和通过性能研究

行驶性能和通过性能是评估车辆越野性能的基本指标。为得到八轴连通式油气悬架车辆的越野性能,分别对行驶性能和通过性能开展了研究。简化了整车的物理模型,根据拉格朗日方程推导了车辆的振动方程,建立了白噪声路面输入方程;通过仿真结果与实验结果的对比,验证了柔性模型的合理性。基于柔性模型,以路面不平度系数为输入变量,得到了车辆在较好路面、一般路面、较差路面、恶劣路面的行驶性能;通过建立脉冲冲击、台阶冲击、震荡冲击的数学模型,得到了车辆的通过性能。结果表明:随着路面等级变差,八轴车辆的极限车速下降,B级路面极限速度为144 km/h,C级路面极限速度为64.8 km/h,D级路面极限速度为32.4 km/h,E级路面极限速度为7.2 km/h;路面冲击类型主要影响车头的加速度和车轮相对动载的极值,脉冲冲击时车轮发生腾空,且车头垂向加速度超过2.5倍重力加速度,而台阶冲击和震荡冲击均未出现轮胎腾空和车头2.5倍重力加速度的过载。

A study on driving performance and passing performance of the vehicle with eight-shaft interconnected hydro-pneumatic suspension

Driving performance and passing performance are the basic indicators to evaluate vehicles’off-road performance.To obtain the off-road performance of a vehicle with eight-axis connected hydro-pneumatic suspension,the driving performance and passing performance were studied.Firstly,the physical model of the whole vehicle was simplified,the vibration equation of the vehicle was deduced according to the Lagrangian equation,and the white noise road surface input equation was established.The rationality of the flexible model was verified by comparing simulation results with experimental results.Based on the flexible model and the road roughness coefficient as the input variable,the driving performance of the vehicle on different roads was obtained.By establishing the mathematical models of pulse impact,step impact and shock impact,the passing performance was obtained.The results show that with the deterioration of the road level,the limit speed of the eight-axle vehicle was reduced,the limit speed of the B-level road surface is 144 km/h,C-level road surface is 64.8 km/h and the D-level road surface is 32.4 km/h,the E-level road surface is 7.2 km/h.The road surface impact type mainly affects the vehicle-head acceleration and the extreme value of the wheels’relative dynamic load.The wheel takes off when the pulse impact occurs,and the vehicle-head acceleration exceeds 2.5 times the gravity acceleration,while the step impact and the shock impact do not appear the wheel taking off and the 2.5 times gravity acceleration overload.