3-DIMENSIONAL FINITE-ELEMENT ADAPTIVE ANALYSIS OF INCOMPRESSIBLE-FLOWBASED ON CONTROL OF NODE DENSITY DISTRIBUTION AND A-POSTERIORI ERROR ESTIMATION

In finite element analysis, it is not economical to use a uniformly fi ne mesh in the whole domain in order to obtain the required accuracy. However, in the analysis of fluid flows it is hard to predict the loca tions of the region with large gradients, and, especially in time-depe ndent problems, the large gradient regions might change their shapes a nd locations, or even disappear. Thus, it is difficult for the enginee rs to control empirically the mesh size and construct a proper mesh. F or constructing a proper mesh, it is important to estimate the error a ppropriately as well as to make automatically a faithful mesh reflecti ng the error distributions. In this paper, the mesh generator is incor porated into the adaptive analysis strategy based on an a posteriori e rror estimation, and this adaptive procedure is applied to the analyse s of three-dimensional incompressible viscous flows. The global percen tage error, the degree of freedom and the accuracy of the solution are compared with those of the conventional method using the regular mesh . Numerical examples of the 3-D driven cavity flows of Re = 1000 and R e = 3200 have shown the very high performance of the proposed adaptive procedure. (C) 1997 Elsevier Science Limited.