Abstract:The distribution of isentropic Mach number of the airfoil’s suction side and pressure side accords with the control diffusion criteria, made the design point losses low and the operating range wide. In order to study the influence of the load distribution on the aerodynamic performance of cascades, an automatic optimization design method for controlled diffusion airfoils is established, several load distribution designs are carried out for stator and rotor airfoils with the inlet Mach number of 0.7, then the influence of the load distribution law on the performance of the cascades is analyzed. The results show that for stator and rotor airfoils, front-loading (forward to 0.1 times of the relative axial chord length) is helpful to inhibit boundary layer development, reduce the design point loss and increase the operating range; the peak Mach number of suction side increases, the camber near the leading edge of airfoil suction side increases, loss under small incidence increases and the inlet flow angle corresponds to the minimum loss increases.