HELICOPTER ROTOR AERODYNAMIC PERFORMANCE PREDICTION BASED ON FLOW SIMULATION AROUND AIRFOILS

With the increase of flight speed, helicopter rotor aerodynamic environment becomes complicated. Transonic flow near the forward blade tip and reverse flow near the backward blade root occured at the same time. In order to estimate rotor aerodynamic performance, the CFD simulation around airfoils on various working conditions were carried out. First, transient flow simulations around NACA0012 airfoil were tested for various turbulence models at several working conditions (Ma number 0.28~0.8, angle of attack 10~20̊, 160~180̊). Results were compared with experimental values. It was found that the Realizable k-epsilon turbulence model was closer to the test than kkl omega turbulent model. The errors of the lift coefficient and drag coefficient were -46.7~56.3% and -66.2~27.5% respectively. Secondly, airfoils on the XH-59A helicopter rotor (NACA0026, NACA63-213, NACA63-218, NACA63-224 and NACA230125) were simulated in various working conditions. Finally, with the airfoil performance database provided, the rotor performance in advance ratio 0.1~0.4 was obtained based on momentum blade element theory.