3D Incompressible Flow Simulation Using Finite Volume Method on Unstructured Meshes

In this paper, a cell vertex finite volume algorithm is presented for the simulation of 3D incompressible fluid flow on unstructured meshes. The algorithm uses an efficient edge-based data structure. The artificial compressibility concept is employed to utilize the continuity equation to couple the pressure and velocity of the fluid. The steady solution is computed using an explicit multi-stage Runge-Kutta time stepping, which is found to be efficient in terms of CPU and memory overheads. To accelerate convergence, a multigrid scheme with automatic creation of coarse meshes is used. In order to improve the convergence, the Turkel’s preconditioning is also employed. A dual time approach is used in order to obtain unsteady solution. For the physical time step, the implicit backward time step is used and the explicit multi-stage Runge Kutta pseudo time is employed for the inner iteration. Several cases with various geometric complexity are presented to show the effectiveness of the multigrid implementation and to evaluate the accuracy of the proposed scheme. Therefore it is used as prediction tools for practical problems. From these cases, it can be concluded that the scheme with multigrid acceleration technique can be used for the simulation of incompressible flow from simple to complex geometries by using unstructured meshes accurately and efficiently.