油气悬架粘性发热研究与优化

Viscous heating of hydro-pneumatic suspension and its optimization

针对矿用自卸车行驶道路恶劣载重量大、致油气悬架粘性发热显著、阻尼力偏离设计值甚至产生气穴加剧部件损坏等,对油气悬架粘性发热进行研究、优化。用龙格-库塔公式求解油气悬架非线性热平衡方程,并建立热动力学模型;通过仿真与试验对比,簧上质量加速度响应最大误差为5.5%,较未考虑粘性发热精度时提高4.2%,从而验证模型的准确性。通过对粘性发热现象定量分析表明,E级路面温度升高达65 K,D级路面温度升高达38 K;粘性发热使悬架系统共振频率偏移,幅值发生变化。基于惩罚函数法建立目标函数,采用遗传算法优化后油气悬架温度降低14 K。

Mining dump truck with heavy loads are usually driven on rough roads,which produces obvious viscous heating of hydro-pneumatic suspension,and the damping force generally may deviate from the design value,even cause cavitation and parts damaged,so it is important to research and optimize the viscous heating. Runge-Kutta formula was used to slove the nonlinear heat balance equation and establish a thermal dynamics model. By comparing the results of simulations and experiments it is shown that the maximum error of sprung mass＇ acceleration is 5. 5%,which indicates the precision is improved by 4. 2% as compared with that in the case without considering viscous heating. This proves the corretness of the model and effectiveness of the method. The viscous heating behavior was further explored quantitatively：the temperature rises 65 K on E level road,and on D level road which trucks often drives on,the increment is 38 K.Meanwhile the viscous heating results in a shift of the resonance frequency and a change in the vibration magnitude.Finally,an objective function was established based on the penalty function method,and was optimized by using genetic algorithm. The temperature decreases by 14 K after optimization.