A design of an annular cascade tunnel and a cascade of airfoils

Abstract

A low speed annular cascade wind tunnel was designed and constructed and is presently installed in the MIT Gas Turbine Laboratory. It is anticipated that this tunnel will be used to secure data for correlation with three dimensional theory of flow in an annular cascade, particularly applicable to the design of compressor inlet guide vanes. An annular cascade of thirty-six airfoils having a cubic variation of circulation with radius was designed for use in the tunnel. Construction of this cascade is pending. Another annular cascade of fifty-four airfoils is installed in the tunnel awaiting test upon completion of instrumentation. A three dimensional vortex theory of flow in an annular cascade, developed by Dr. W. E. Hawthorne, is presented. This theory was employed in the design of the thirty-six airfoil cascade.