Note on the Concept of Blunt Trailing Edge Blades

摘要

The concept of blunt trailing edge blading for use in supersonic axial compressors is described, and its expected advantages and disadvantages are discussed. Its basic features - the possibility of decelerating a supersonic flow to subsonic velocities by means of a multiple shock system - are shown to be valid, as well as the possibility of having efficient deceleration by a sudden increase in flow passage area, if this change of area is kept within certain limits. Use of a constantly diverging section proves beneficial for operation in subsonic, transonic and supersonic flows. The advantage of using a twisted blading for the rotor is shown by the experimental results. Satisfactory cascade, rotor and stage performances were obtained with a wide range of bladings using the concept, from subsonic to supersonic speeds. Its potential could be used in both low and high hub to tip ratio supersonic compressor stages. (Author)