ABSTRACT
A grid manipulation algorithm is presented that allows CFD calculations in complex moving geometries using block-structured grids. An Arbitrary Lagrangian-Eulerian formulation of the flow problem is used. In terms of grid manipulation, this means that grid nodes are moved in-between time steps without changing the grid topology. The focus of the paper lies on the development of the grid manipulator.
The block-structured grids are constructed from the solution of the Laplace equation ∇²(Φ) = 0 obtained on an unstructured grid in the same geometry. High quality meshes are constructed from the gradient lines and the potential lines. As an illustration, a calculation of compressible flow in a screw compressor is set up with the constructed meshes.