NUMERICAL NEAR-FIELD SIMULATIONS OF LOW BOOM AIRCRAFT CONCEPTS

This paper presents the setup of the DLR TAU code for sonic boom near-field simulations and results obtained for the low-boom geometries developed within the EC project RUMBLE. A process for surrogatebased low-boom low-drag fuselage design based on a near-field target pressure signature is described. The focus of the paper is the robust parameterization of the fuselage geometry to prevent the generation of irregular shapes as well as the modular grid generation approach that significantly reduces the time to generate the grids. The numerical results of four RUMBLE milestone shape evolutions with flow through nacelles are presented and geometrical influences on the near-field pressure signatures are analyzed. It is shown that the pressure signatures for shape derivatives with powered engine boundary conditions or with modifications for wind tunnel measurements are very similar to the signatures of the original shapes.