Numerical prediction of the effects of condensation of moist air on the aerodynamic characteristics of the RAE 2822 airfoil

The aerodynamic characteristics of airfoil may be influenced obviously by the nonequilibrium condensation of water vapour carried by transonic moist air flow. A numerical method was developed to solve the moist air flow with nonequilibrium condensation. The transonic flows around the RAE 2822 airfoil with non-equilibrium condensation were simulated at 2.54°angle of attack with different humidity. It was concluded that the structure of the supersonic region is changed obviously with an increase in the relative humidity, compared with that in the dry air flow field. A complex multishock wave system is observed at the relative humidity of 60% and 75%, respectively. The lift coefficient and the pressure drag coefficient decrease with an increase of the relative humidity. At relative humidity of 75%, the lift coefficient decreases by 15.7%, and the pressure drag coefficient by 53.2%. The variations of the nucleation rate and the condensate mass fraction, therefore the alteration of the influence of heat addition on the flow field, are responsible for the changes of the aerodynamic characteristics of RAE 2822 airfoil.