Drag and lift in nonadiabatic transonic flow

Lifting and nonlifting transonic flows around single airfoils have been calculated including heat addition from partialphase change of the fluid Itself. Fordemonstration of the limits of possible effects in nonadiabatlc aerodynamics, two different processes are Investigated: Nonequilibrium heat addition after homogeneous nucleation and equilibrium condensation. The numerical calculation is based on the Euler equation, linked with either the classical nucleation theory and microscopic or macroscopic droplet growth laws, or an equilibrium condensation process. An improved explicit, time dependent, diabatic finite volume method is developed to calculate steady flows. For internal flows with homogeneous nucleation the pressure drag may increase or decrease about 60% and 25%, respectively. Simultaneously the lift decreases up to 35%. Assuming thesame process for atmospheric flight simulations, the lift decreases more than 10%, Equilibrium condensation increases the lift about 30% and raises the pressure drag substantially, more than 200%.