Condensation on ONERA M6 and F-16 wings in atmospheric flight: Numerical modeling

A numerical investigation of the adiabatic and condensing flowfield around the ONERA M6 and F-16 Falcon wing is performed. For the ONERA M6 wing, three different mean aerodynamic chord c_mac lengths, 0.5, 1.0, and 2.0 m, three angles of attack, 1.07, 3.06, and 6.06 deg, and three different number densities of particles, 106, 10¹², and 10¹⁶ m ^-3, are analyzed. At 10⁶ m^-3, the flow is dominated by homogeneous condensation, and due to the large chord length, the effects of condensation are small. As the particle density increases, a mixture of homogeneous/heterogeneous condensation occurs at 10¹² m ^-3, and at 10¹⁶ m^-3, only heterogeneous condensation occurs. For the F-16 Falcon wing, the size of the wing and the number density of particles 10¹² m^-3 are kept constant. The angle of attack and freestream Mach number are changed, where a decrease in the lift-to-drag ratio reached 20%. In general, if the wing is experiencing separation, condensation can improve the lift-to-drag ratio, whereas for attached flow with small flight angles, condensation reduces the lift-to-drag ratio.