Extension of a 3D Time-Accurate Euler Code to the Calculation of Multibladed Rotors in Forward Flight without Wake Modelling

Abstract

The time-accurate 3D Euler code of DLR SM-EA is applied to the LANN CT5 test case. The first two Fourier components of the pressure coefficient are compared to the experimental data showing a shock position which is too far downstream due to the lack of viscous effects in the numerical simulation. 2D and 3D time-accurate Euler solvers for overlapping grids (chimera technique) have been developed. The chimera algorithm uses linear interpolation of the flow variables at the chimera boundaries. 2D results for an incompressible wing-flap test case are presented and compared with the analytical solution showing an excellent agreement. The 3D chimera solver has been applied to a lifting 3-bladed rotor in forward flight. The pressure distributions are compared to the experimental data and to an isolated blade computation which is coupled with a wake model. The overall agreement of the chimera solution with the experimental data is better than the solution based on a wake model.