Turbomachinery Vibration Analysis with a New Parallel Time Decomposition Scheme

Current time-marching methods for assessing periodic blade loads consume inordinate computational time, greatly restricting analysis and design based on such approaches. This study seeks to redress this drawback by implementing a novel time-domain decomposition algorithm on a parallel computer. This parallel scheme will achieve orders of magnitude reduction in computation times while making full use of existing sequential algorithms for simulating periodic systems on parallel computers. Perfect load balance will be accomplished and inter-processor communication minimized using the proposed scheme. Though the parallel algorithm is applicable to any time-periodic system this effort will focus upon the rotor-stator interaction problem using an existing highly accurate aeroelastic analysis. By basing the analysis on a validated fluid-structure interaction code, another drawback of existing rotor-stator codes namely the absence of a true aeroelastic capability will be repaired. In Phase I, validation exercises will be conducted on a parallel machine in order to assess the coding effort entailed in adapting an existing serial code to parallel computation and CPU gains over serial methods using the proposed technique. In Phase II. the technique will be extended to full 3D viscous aeroelastic turbomachinery rotor-stator computations on a parallel machine.