过滤器滤网颗粒物分布特性的数值模拟

Numerical Simulation of Particle Distribution Characteristics on Filter Screen

过滤器对保障液压系统的正常运行起到重要作用,为了提升液压系统的性能,对过滤器也提出更高的要求。为了厘清过滤器内部滤网前后污染颗粒的分布情况,建立某型过滤器计算流体动力学模型,通过过滤器上下游压差与流量关系实验测试结果,拟合得到多孔介质的黏性阻力系数和惯性阻力系数,完成多孔介质边界条件参数设置后,分别从速度入口和压力入口两方面,模拟滤网上游和下游污染颗粒分布情况。结果发现尺寸大于滤网孔径的颗粒主要分布在上端盖4个进口的正下端和下半部分滤网的周围。穿过滤网的小粒径污染颗粒在骨架内部的分布沿骨架内壁面,呈上半部分分布密度大,下半部分分布密度小的状态。研究结果为过滤器设计提供一定参考。

The filter plays an important role in ensuring the normal operation of the hydraulic system.In order to improve the performance of the hydraulic system,higher requirements been given to the filter.In order to clarify the distribution of contaminated particles in the filter,a computational fluid dynamics model of a certain type of filter was established.The viscous resistance coefficient and inertial resistance coefficient of the porous medium model was obtained by fitting the experimental results of the relationship between the pressure difference and flow of the filter.After setting the parameters of porous media boundary conditions,the distribution of contaminated particles at the upstream and downstream of the filter screen was simulated from the two aspects of velocity inlet and pressure inlet.It was found that the particle accumulation density in the fluid domain of the upper shell of the filter was large.Particles larger than the diameter of the filter screen are mainly distributed at the lower end of the four inlets of the upper end cover and around the lower half of the filter screen.small-sized contaminated particles enter the skeleton through the filter screen,and the distribution density of the upper part is high,and the lower part is low.The research provides a reference for the filter design.