Abstract: The ducted ram air turbine is the key component that provides energy to Pod Power Supply System (PPSS), and its performance effects the PPSS efficiency importantly. Based on investigating air-dynamics characteristics of blade with different aerofoils, NACA6321, NACA23015 and NACA4412 are chosen as the turbine blade aerofoil of NACAZ1, NACAZ2 and NACAZ3 respectively, which are used for experimental turbine blades in PPSS. The relationships among thrust coefficient, torque coefficient, power coefficient and blade top speed ratio of the blades mentioned above are calculated by optimum Glauert method. Calculation results show that the thrust coefficient and torque coefficient of NACAZ2 blade are maximum, and those of NACAZ1 blade are minimum at same wind speed. As the blade top speed ratio is 2, the power coefficient of NACAZ2 blade is 1.16 times than that of NACAZ1 blade. Experiment verifies that the power coefficient of NACAZ2 blade is maximum, and the power coefficient of NACAZ3 blade is close to that of NACAZ2 blade. The power coefficient of NACAZ2 blade is 37% bigger than that of NACAZ1 blade at blade top speed ratio 2. The calculation and experimental results indicate that the synthetic capabilities of NACAZ2 blade are better, which behaves as bigger torque coefficient, quicker start-up and greater power output at the same wind speed.

Key words: ducted ram air turbine, turbine blade, Glauert method, calculation and experiment analyses, pod power supply system