Use of a Theoretical Flow Model to Correlate Data for Film Cooling or Heating an Adiabatic Wall by Tangential Injection of Gases of Different Fluid Properties

An equation is derived, by use of a simplified theoretical flow model, that predicts the temperature of a film-cooled wnll within 5% for a range of cooling effectiveness from approximately 0.2 to 1.0. The equation is easily solved for required coolant flow rate by a simple iteration process involving continuity. Both helium and air were used as the coolant gas. The range of variables covered by the data is as follows: main-gas-stream temperature, 502 to 1965 deg R: main-gas-stream velcoity, 104 to 1040 ft/sec; velocity natio V/sub g/ /V/sub c/, 0.45 to 33.3; injected gas temperature, 530 to 980 deg R; and coolant slot height, 0.063 to 0.50 inch. (auth)