Berechnung von Stroemungsfelder um Hubschrauberrotoren im Vorwaertsflug durch die Loesung der Euler-Gleichungen

A numerical method for the calculation of the unsteady three-dimensional flow around isolated rotors in high-speed forward flight is described. The method is based on the Euler-equations which have been transformed into a rotating blade fixed coordinate system. The undisturbed flow is an exact solution of the numerical method. The rotor is treated as a system of several rigid bodies (rotor blades) in relative motion. The physical space is discretized using overlapping meshes (chimera-technique). In addition to an explicit Runge-Kutta time-stepping method an implicit time-stepping method was implemented (dual-time method). The chimera-method was applied to several test cases with emphasis on applications to rotors in high-speed forward flight. Except for one test case with a rotor in low-speed forward flight the results of the chimera-method agree well with both the experimental data and the numerical reference solutions. The accurate prediction of the flow around rotors in low-speed forward flight with strong blade-vortex-interactions (BVI) with this chimera-method would require extremely fine grids which would lead to unacceptable computation times. (orig.)Available from TIB Hannover: RA 437(99/22) / FIZ - Fachinformationszzentrum Karlsruhe / TIB - Technische InformationsbibliothekSIGLEDEGerman