基于动态混合网格的鱼体巡游数值模拟  

Numerical simulations of swimming fish with hybrid moving mesh technique

作　　者：张来平[1] 常兴华[1] 段旭鹏[1] 王振亚[1] 张涵信[1] 

机构地区：[1]中国空气动力研究与发展中心,四川绵阳621000

出　　处：《空气动力学学报》2007年第B12期29-36,共8页Acta Aerodynamica Sinica

基　　金：国家自然科学基金（10321002,90405014）;中国空气动力研究与发展中心创新基金.

摘　　要：对鱼类等柔性变形体的数值模拟需要解决如下几个问题：（1）柔性体动态网格生成；（2）基于动态网格的不可压流非定常算法。本文基于Delaunay背景网格插值方法，发展了一套快速生成柔性体变形的动态混合网格生成方法；对于不可压流问题，采用虚拟压缩方法进行求解，结合双时间步方法来处理非定常问题；最后数值模拟了鱼体巡游的非定常流动，分析了鱼体的摆动频率对力、功耗等流体动力学特性的影响。Recently, research on bio-fluid dynamics has become widespread all over the world. For swimming fish, their bodies deform flexibly with moving, and the flows around them are strongly unsteady. To simulate the unsteady flows over swimming fishes, dynamic grid technique and corresponding flow solver should be set up firstly. In this paper, a hybrid dynamic grid technique based on Delaunay background grid technique and local remeshing is presented firstly. In order to carry out bio-fluid simulations, an incompressible Navier-Stokes numerical solver on the hybrid dynamic grid is presented also based on the artificial compressibility method with dual-time stepping for time advancing. Finally we simulate the unsteady flows of the swimming fish with different phase speeds. The influence of the phase speed （C） on the flow structures and force characteristics are analyzed. The total drag decreases monotonically as C exceeds a threshold value, which means the fish is propelled by thrust. The results increases and becomes negative when C agree very well with those of references.

关 键 词：动态混合网格 双时间步方法 虚拟压缩方法 生物仿生流体力学 

分 类 号：V211.3[航空宇航科学与技术—航空宇航推进理论与工程]