摘要
针对混凝土泵车的工作原理和结构特点,结合现有输送管流固耦合理论的研究成果,提出了基础有平动位移的悬臂输送管理论模型,并通过多体运动学理论和Hamilton变分原理,建立该模型的运动微分方程。采用有限单元理论建立混凝土泵车臂架系统的流固耦合运动微分方程。选取混凝土流速U=2.265m/s和不考虑混凝土流动进行对比仿真分析后发现:两者臂架振动响应均值相同;但稳态时两者振动幅值比值最大,接近2;而改变Rayleigh阻尼系数则对臂架振动响应影响不大,这说明混凝土的流动增加臂架振动阻尼效应显著。结合Matlab仿真分析与Ansys三维有限元模型,模拟计算出了臂架结构动应力,对比测点应力测试结果与模拟计算结果,两者应力历程变化趋势相似,应力值较接近,最大差异小于20MPa,验证了仿真模型的合理性。
The horizontally moving fluid-tube cantilever model is put forward by incorporating the structural features of pump truck and the related results on cantilever pipe conveying fluid.Dynamic differential equation of the model is derived based on multi-body kinematic theory and Hamiltonian variational principle.The dynamic differential equation of arm system of pump truck is set up by using finite element method.Two cases are studied: the concrete fluid flow velocity is 2.265m/s and the concrete fluid is static.The mean value of vibration response of arms is identical and the maximum amplitude ratio is approximate to 2.Two cases with the Rayleigh damping ratios of 0 and 0.00845,respectively,are studied,the results indicate that the amplitude ratio is approximate to 1.It is concluded that the concrete fluid flowing can enhance the structural damping significantly.Compared the simulation results which are carried out by MATLAB and ANSYS with the measured results,a similar changing trend of dynamic stress history is verified.The simulation results of stress are close to the measured results,and the maximum difference is less than.By comparison the availability of our method is confirmed.
出处
《应用力学学报》
CAS
CSCD
北大核心
2011年第2期139-143,213,共5页
Chinese Journal of Applied Mechanics
基金
中央高校基本科研业务费专项基金(CHD2009JC153)
长安大学基础研究支持计划专项基金
