Accession Number : AD0282900

Title :   ABNORMAL AERODYNAMIC CONDITIONS WITHIN THE PWT SUPERSONIC TUNNEL COMPRESSOR AND THEIR EFFECTS ON ITS DYNAMIC CHARACTERISTICS

Corporate Author : ARNOLD ENGINEERING DEVELOPMENT CENTER ARNOLD AIR FORCE STATION TENN

Personal Author(s) : ROBINSON,R.A.

Report Date : AUG 1962

Pagination or Media Count : 1

Abstract : During the initial shakedown and calibration of the compressor of the PWT 16-Ft Supersonic Tunnel, several abnormal aerodynamic conditions occurred within the compressor. Turbining, abnormal wakes, stalls, and surges occurred. Records of these conditions show their effect on the dynamic characteristics of the compressor. The results indicate that all four conditions cause marked departures from the normal dynamic characteristics. Stalls and surges had the greatest effects on all the measured quantities. Several different types of stalls and surges were observed and recorded. Stalls without surges; surges with rotating stalls only; surges with a complete flow breakdown and reversal, which was the most frequent type; and mixtures of surges and stalls were encountered. The effects of stator blade angle, number of stages, pressure level, and compressor speed were recorded. All stalls and surges produced definite dynamic patterns. The type of pattern depended on the type of stall or surge. Turbining caused large changes in both static and dynamic stresses of the stator blades. Abnormal wakes from single stator blades caused large changes in both stator and rotor blade vibratory stresses. (Author)

Descriptors :   *AXIAL FLOW COMPRESSORS, *SUPERSONIC WIND TUNNELS, AERODYNAMIC CHARACTERISTICS, AXIAL FLOW COMPRESSOR BLADES, DYNAMICS, STALLING, STRESSES, SUPERSONIC FLOW, WAKE

Distribution Statement : APPROVED FOR PUBLIC RELEASE