Simulations of propeller/airframe interference effects using an euler correction method

An Euler correction method has been used to study propeller effects in airframe-integration studies. In the present method, the propeller is modeled by an actuator disk with proper jump conditions prescribed along the disk. The rotational flowfield behind the propeller is analyzed using the Clebsch formulation of the Euler equations, while the remaining irrotatiohal flowfield is determined with the full-potential method. This method has been successfully implemented into existing axisymmetric nacelle and aft-fuselage/pylon/nacelle codes to study power effects in the presence of a counter-rotating propfan of the pusher type. In the subsonic flow regime where the effect of power is prominent, comparisons of the results obtained using the present method against those of the panel method and experimental data suggest that this simple method is adequate. In the transonic flow regime, calculations indicate that power effects can increase wave drag and trigger earlier shock-induced flow separation.