Application of the Standard Aeronautical CFD Method FLOWer to Trains Passing on Open Track

The time-accurate 3D Euler/Navier-Stokes code FLOWer of DLR is applied to trains passing on open track test cases. One test case with the German ICE and three test cases with the Italian ETR500 high speed train were selected. It turned out that the accuracy requirements for train passing applications are very high because absolutely and relatively small pressure differences, compared to typical aeronautical applications, have to be resolved. In order to reach the required accuracy the grid quality in terms of grid fineness and smoothness (cell stretching, cell distortion) on the surfaces and in the flow field is of primary importance. The paper addresses the numerical problems encountered during these applications. Computed pressure signals are compared with full scale measurements. It is shown that FLOWer is able to accurately compute train passing configuration but with a high computational effort.