Parallel implementation of an upwind Euler solver for hovering rotor flows

Abstract

Abstract An Euler method for computing compressible hovering rotor flows is described. The equations are solved using an upwind finite-volume method in a blade-fixed rotating co-ordinate system, so that hover is a steady problem. Transfinite interpolation, along with a periodic transformation, is used to generate grids for the periodic domain. Computation of these flows to an acceptable accuracy requires fine grids, and a long integration time for the wake to develop, resulting in excessive run times on a single processor. Hence, the method is developed as a multiblock code in a parallel environment, and various aspects of data passing and communication between processors have been considered. It is shown that a considerable increase in performance is available from the use of non-blocking and asynchronous communication. It is also demonstrated that increased performance may be available by balancing the residual levels rather than the number of cells on each processor.