Accession Number : ADA298470

Title :   Numerical Unsteady Aerodynamic Simulator for Blade Forced Response Phenomena.

Descriptive Note : Final rept. 1 Jun 92-1 Dec 94,

Corporate Author : UNITED TECHNOLOGIES RESEARCH CENTER EAST HARTFORD CT

Personal Author(s) : Ayer, T. C. ; Verdon, J. M.

PDF Url : ADA298470

Report Date : DEC 1994

Pagination or Media Count : 72

Abstract : This report describes the application of a modem, time-accurate, Euler/Navier-Stokes analysis to the prediction of unsteady subsonic and transonic flows through a two-dimensional cascade. In particular, unsteady flows excited by harmonic, pure torsional and pure bending vibrations of the blades of the Tenth Standard Cascade. The purpose of this study is to validate the Euler/Navier-Stokes analysis along with an existing linearized inviscid analysis for unsteady flows that are representative of those associated with blade flutter in modem fans and compressors. The analysis is also applied to determine the relative importance of nonlinear and viscous effects in the unsteady response of a cascade to prescribed blade motions. The results of the study indicate a close agreement between inviscid and viscous blade loadings for unsteady subsonic flows. For unsteady transonic flows, shocks and their motions introduce significant nonlinear or second and higher harmonic contributions to the local unsteady response.

Descriptors :   *MATHEMATICAL MODELS, *COMPUTATIONAL FLUID DYNAMICS, *UNSTEADY FLOW, VIBRATION, MOTION, BENDING, BLADES, PURITY, NONLINEAR SYSTEMS, RESPONSE, LINEARITY, AERODYNAMIC CHARACTERISTICS, FANS, EULER EQUATIONS, SUBSONIC FLOW, COMPRESSORS, MODEMS, NAVIER STOKES EQUATIONS, INVISCID FLOW, VISCOUS FLOW, VISCOSITY, REYNOLDS NUMBER, FLUTTER, TORSION, TRANSONIC FLOW, CASCADES(FLUID DYNAMICS).

Subject Categories : Operations Research
      Fluid Mechanics

Distribution Statement : APPROVED FOR PUBLIC RELEASE