基于有限元的平房仓内部粮食颗粒摩擦力分析

FRICTION ANALYSIS OF GRAIN PARTICLES IN A FLAT WAREHOUSE BASED ON FINITE ELEMENT METHOD

为探究粮食颗粒内部之间的应力分布以及颗粒与仓壁之间的相对静摩擦力的分布规律,在考虑粮食颗粒压缩性对粮堆剪胀参数影响的情况下,通过理想弹塑性本构关系和Drucker-prager屈服准则,并采用非关联流动法则来模拟储料,建立了粮仓仓壁与粮食之间正压力、相对静摩擦力的有限元模型,分别模拟不同装粮高度下仓壁与粮食之间的相对静摩擦力、正压力等,找到不同装粮深度处仓壁的相对静摩擦系数的分布规律。结果表明,不同装粮高度处的相对静摩擦系数是不同的,具体表现为伴随深度的增加,系数先增加后减小。可见,粮食颗粒相互间的作用力以及颗粒与仓壁之间的静摩擦力对粮食重量的测量具有十分重要的指导意义。

In order to study the stress distribution between grain particles and the distribution law of relative static friction between grain particles and grain wall,considering the effect of grain particle compressibility on the shear dilatancy parameters of grain stack,the positive pressure between grain and grain wall was established by means of ideal elastic-plastic constitutive relationship and Druceke-prager yield criterion,and the non-correlative flow rule was used to simulate grain storage.The finite element model of relative static friction was used to simulate the distribution of relative static friction coefficients of silo walls at different grain loading depths.The results show that the relative static friction coefficients are different at different grain filling heights.The specific performance is that with the increase of depth,the coefficient increases first and then decreases.It can be seen that the interaction force between grain particles and the static friction force between grain particles and warehouse wall have very important guiding significance for the measurement of grain weight.