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

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.

Document Details

Document Type
Technical Report
Publication Date
Jan 01, 1982
Accession Number
ADP000362

Entities

People

  • Frank J. Laudadio
  • John M. Vance

Organizations

  • Texas A&M University

Tags

DTIC Thesaurus Topics

  • Aerodynamic Forces
  • Axial Flow
  • Blade Tips
  • Blades
  • Clearances
  • Coefficients
  • Eccentricity
  • Flow
  • Instability
  • Mathematical Models
  • Measurement
  • Models
  • Stiffness
  • Turbomachinery
  • Verification

Fields of Study

  • Physics

Readers

  • Aerodynamics.
  • Theoretical Analysis.
  • Tribology (the study of the boundary interaction between sliding surfaces, lubrication, wear and friction).