In the present study a high-order accurate numerical method is used to investigate problems related to helicopter rotors in high-speed forward flight. Numerical results are presented for compressible turbulent flows past oscillating airfoils both in transonic regime (advancing blade tip), including shock-stall conditions, and for a difficult dynamic stall problem of an airfoil oscillating at high angle of attack (retreating blade). The capabilities and the computational costs of different physical models (Euler equations, RANS equations with algebraic and with transport-equation turbulence models) are investigated and the numerical difficulties arising in the simulation of strongly separated turbulent flows are shown up. For these flows, and especially for the dynamic stall problem, the solution is found to be extremely sensitive to the numerical scheme, mesh density and time-step.
A study of turbulent compressible flows over oscillating airfoils by a high-order accurate numerical scheme
CINNELLA, Paola;
2001-01-01
Abstract
In the present study a high-order accurate numerical method is used to investigate problems related to helicopter rotors in high-speed forward flight. Numerical results are presented for compressible turbulent flows past oscillating airfoils both in transonic regime (advancing blade tip), including shock-stall conditions, and for a difficult dynamic stall problem of an airfoil oscillating at high angle of attack (retreating blade). The capabilities and the computational costs of different physical models (Euler equations, RANS equations with algebraic and with transport-equation turbulence models) are investigated and the numerical difficulties arising in the simulation of strongly separated turbulent flows are shown up. For these flows, and especially for the dynamic stall problem, the solution is found to be extremely sensitive to the numerical scheme, mesh density and time-step.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.