基于FEM-SPH耦合的离心机抛填土料冲击行为数值分析  

Numerical simulation for centrifuge throw-filling soil impact behavior based on FEM-SPH coupling

作　　者：钟卫洲[1] 杨玉明[1] 郝志明[1] 刘显军[1] 邓志方[1] 

机构地区：[1]中国工程物理研究院总体工程研究所,四川绵阳621999

出　　处：《振动与冲击》2016年第19期206-212,共7页Journal of Vibration and Shock

基　　金：国家自然科学基金(11302211;11390361;11472257)

摘　　要：利用有限元(Finite Element Method,FEM)与光滑粒子流体动力学方法(Smoothed Particle Hydrodynamics,SPH)耦合的方法对离心机抛填土料动力响应进行分析,数值模型中离心机结构部件采用传统拉格朗日单元,土料采用无网格光滑粒子,实现了无黏性土料连续冲击离心机结构行为的数值再现。基于土料以5 m/s、10 m/s速度分别冲击离心机料斗与土料箱底算例进行分析,获得了离心机抛填结构在土料连续冲击作用下的应力分布和等效冲击载荷;在5 m/s速度冲击料斗冲击过程中,最大应力出现在离心机支撑装置横截面处,料斗结构上产生的最大等效应力为292 MPa;土料10 m/s冲击土料箱计算时,箱体底部铺设的橡胶垫层能降低冲击载荷幅值,实现对土料箱体结构的有效缓冲作用。数值分析结果表明,结合FEM高计算效率特点以及SPH耦合方法易于处理大变形优势,FEM-SPH耦合方法可以实现对土料类离散体冲击大变形行为数值模拟,有助于提高结构动态大变形响应过程模拟的逼真度和置信度。Soil continuous impact behavior of a centrifuge throw-filling equipment was simulated using finite element method ＆ smoothed particle hydrodynamics （FEM-SPH） coupling method. Centrifuge structural components were modeled with Lagrangian finite elements and meshless smoothed particles were used for soil model in numerical simulation. Continuous impact processes of cohesionless soil, were reproduced numerically with FEM-SPH coupling. When soil impacting centrifuge hopper and soil box bottom at speeds of 5 m/s and 10 m/s, respectively, the stress distribution and equivalent impact load of the centrifuge structure were gained under soil continuous impacting condition. It was shown that the maximum equivalent stress is 292 MPa on the cross section of the centrifuge support device under the condition of soil impacting hopper at the spead of 5 m/s; rubber layer cushion on the soil box bottom can reduce impact loading amplitude when soil impacts the box bottom at speed of 10 m/s; the rubber layer can protect the box structure from soil’s continuously impacting; FEM simulation has a high computational efficiency and SPH method is a good way to describe structural large plastic deformation and damage, so the FEM-SPH coupling method can be applied to simulate soil-like material＇s large deformation behavior, it is helpful for improving numerical simulation＇s fidelity and confidence level.

关 键 词：土料冲击 冲击动力学 离心机 无网格方法 FEM-SPH耦合 

分 类 号：O347[理学—固体力学]