Air University of Shahid Sattari, Tehran, Iran
K.N.Toosi University of Technology, Center of Excellence for Design and Simulation of Space Systems, Tehran, Iran
In this paper the effects of ice accretion on the pressure distribution and the aerodynamic coefficients in a cascade of stator blades were experimentally investigated. Experiments were conducted on a stage 67A type stator Controlled-Diffusion blades, which represent the mid-span of the first stage of the stator for a high-bypass turbofan engine. The measurements were carried out over a range of cascade angle of attack from 20 to 45 at Reynolds number of 500000. Experimental blade surface pressure coefficient distribution, lift and drag force coefficients, and momentum coefficients for clean blades were compared with those of the iced blades and the effects of ice accretion on these parameters were discussed. It is observed that the ice accretion on the blades causes the formation of flow bubble on the pressure side, downstream of the leading edge. By increasing the angle of attack from 20 to 35 , the bubble length decreases and the pressure coefficient increases inside the bubble region, constantly. In addition, for the iced blades the diffusion points at the suction side come closer to the trailing edge. In addition, it is found that by increasing the angle of attack up to 35 , the ice accretion has no significant effect on the lift coefficient but the drag coefficient increases comparing with the clean blades. More over at 40 and 45 , by increasing the flow interference effects between the blades, the iced blades experience higher lift and lower drag in comparison with the clean ones.