Development of an Algorithm for Dynamic Grid Generation

Any computational fluid dynamic study would involve the generation of grid points over which properties are to be evaluated and most of the problems are dynamic in nature where the position of the body itself is a function of time. Dynamic grid generation has become indispensable in the field of aerospace, especially in micro-aerial vehicles where flapping wings are employed and in aircraft industry. The current paper concentrates on an algorithm developed for dynamic grid generation to be used in unsteady phenomenon where the spatial position of the body around which the grid is generated, changes with time. A flat plate is taken as a test case and a grid has been generated dynamically using C language. The plate is fixed at one end and flaps at a particular frequency. The momentary boundary points are given as input and the field points are determined for each position of the body. The field points are repelled or attracted from their previous positions and a simple algebraic relation governs the extent of attraction or repulsion. The time taken by this method is approximately 10 times lesser when compared to generating the grid once again for the new position.