柔性翼微型飞行器流固耦合数值模拟

Numerical Simulation of Fluid-Structure Interaction for Flexible Wing MAV

根据分区耦合原理,提出了一种计算流体力学(Computational fluid dynamics,CFD)/计算结构力学(Computational structural dynamics,CSD)的流固耦合计算方法。结构有限元模型基于完全拉格朗日(Total Lagrange,T.L.)格式求解结构几何非线性。气动计算基于有限体积离散的任意拉格朗日-欧拉(Arbitrary Lagrangian-Eulerian,ALE)N-S方程。通过交替数字二叉树(Alternating digital tree,ADT)搜索技术识别两套网格系统之间的宿主-受体关系,采用常体积转换(Constant volume transformation,CVT)和反距离权重(Inverse distance weighting,IDW)法完成网格系统间的数据交换,使用Delaunay图映射法来处理网格移动。将自编的非线性结构有限元程序和接口程序与南航微型飞行器中心的3D2 MUFS流体计算程序相连接,应用于柔性翼微型飞行器的气动计算中。数值计算结果与实验数据吻合良好,验证了该流固耦合计算方法和程序的可靠性和可行性。

A computational fluid dynamics （CFD）/computational structural dynamics （CSD） coupling methodology based on partitioned coupling is presented for fluid-structure interaction.Geometric nonlinearity of the finite element model is calculated base on the total Lagrange （T.L.） scheme.Arbitrary Lagrangian-Eulerian （ALE） N-S equations based on the finite volume method are used for flow field calculation.The donor-receptor relation between two sets of grid system is identified by alternating digital tree （ADT）.The methods of constant volume transformation （CVT） and inverse distance weighting （IDW） are used for data exchange between the two sets of grids.Flow with moving boundaries is dealt with Delaunay graph mapping method.The code for nonlinear structural finite element and data exchange is developed and used to connect with the code of flow solver 3D2 MUFS which has been developed in the MAV center of NUAA.It is applied to the aerodynamic computation of micro air vehicles （MAV）.An excellent agreement is found between the numerical results and the experimental data.It confirms that the approach and code for fluid-structure interaction analysis are reliable and feasible.