Accession Number : ADP000362

Title :   Experiment Measurement of Alford's Force in Axial-Flow Turbomachinery,

Corporate Author : TEXAS A AND M UNIV COLLEGE STATION DEPT OF MECHANICAL ENGINEERING

Personal Author(s) : Vance,John M. ; Laudadio,Frank J.

Report Date : 1982

Pagination or Media Count : 14

Abstract : In 1965, J. S. Alford published a theory and mathematical model (1) which predicts that circumferential variation of blade-tip clearances in axial-flow turbomachinery will produce cross-coupled (normal to the eccentricity) aerodynamic forces on the rotor. Ever since then, the theory has been used (without experimental verification) by rotor dynamicists as one of the few mathematical models available to calculate the cross-coupled aerodynamic stiffness coefficients required for rotordynamic stability analysis. This paper presents the results of experimental measurements made on a small, high speed, axial flow test apparatus to verify the existence of Alford's force and to investigate the validity of his mathematical prediction model.

Descriptors :   *Turbomachinery, *Axial flow compressors, *Rotors, *Aerodynamic forces, *Workshops, Variations, Clearances, Rotor blades, Front ends and surfaces, Theory, Mathematical models, Experimental data

Distribution Statement : APPROVED FOR PUBLIC RELEASE