Accession Number : ADA117361

Title :   Observations of Propagating Stall in a Centrifugal Fan.

Descriptive Note : Final rept.,

Corporate Author : DAVID W TAYLOR NAVAL SHIP RESEARCH AND DEVELOPMENT CENTER BETHESDA MD SHIP PERFORMANCE DEPT

Personal Author(s) : Jennings,Alan N. ; Moran,David D.

Report Date : APR 1981

Pagination or Media Count : 24

Abstract : An experimental investigation has been performed to determine the type of instabilities that are encountered in a centrifugal fan operating against a varying backpressure. In the experimental study, the fan discharge was directed into a flow measuring pipe at the end of which was a rotary valve used to excite the system. Pressure and velocity measurements were taken in the fan volute at several locations. Instabilities detected include rotating stall having one cell and two cell configurations with spontaneous changes between the two configurations. Overall fan performance was not found to be significantly affected by the occurrence of rotating stall.

Descriptors :   *Lift fans, *Centrifugal compressors, Fan blades, Stalling, Surges, Back pressure, Dynamic response, Rotation, Propagation, Aerodynamics, Unsteady flow, Scale models, Test methods, Performance(Engineering), Air cushion vehicles

Subject Categories : Surface Effect Vehicles & Amphibious Vehicles
      Hydraulic and Pneumatic Equipment

Distribution Statement : APPROVED FOR PUBLIC RELEASE