Accession Number : ADP000340

Title :   Effects of Non-Constant Enthalpy Addition on Fan-Nozzle Combinations,


Personal Author(s) : Oates,Gordon C. ; Persz,Walter M. , Jr

Report Date : JUN 1982

Pagination or Media Count : 11

Abstract : It has long been recognized that a compressor or a turbine stage loading may be increased, or the efficiency improved for a given loading, by utilizing a non-constant enthalpy addition to the flow along the length of the blade. The resultant non-uniform flow at exit from the stage will itself have losses identified with it if the flow is passed through a nozzle for propulsive purposes. In order to estimate the expected effect on the thrust of the flow non-uniformities, two limiting cases are herein considered. Thus, an engine with non-constant enthalpy addition across the fan stage, but with otherwise perfect components is considered. The flow is then taken to be (a) completely unmixed (isentropic), and (b) fully mixed in an ideal (no sidewall friction) constant area mixer prior to expansion through the nozzle. In each case the resulting net thrust is compared to that which would exist if the same total enthalpy addition to the fluid stream was supplied uniformly. (Author)

Descriptors :   *Turbofan engines, *Compressors, *Nonuniform flow, *Enthalpy, Exits, Streams, Thrust, Mixing

Distribution Statement : APPROVED FOR PUBLIC RELEASE