Rapid distortion analysis of high speed homogeneous turbulence subject to periodic shear

Abstract

The effect of unsteady shear forcing on small perturbation growth in compressible flow is investigated. In particular, flow-thermodynamic field interaction and the resulting effect on the phase-lag between applied shear and Reynolds stress are examined. Simplified linear analysis of the perturbation pressure equation reveals crucial differences between steady and unsteady shear effects. The analytical findings are validated with numerical simulations of inviscid rapid distortion theory (RDT) equations. In contrast to steadily sheared compressible flows, perturbations in the unsteady (periodic) forcing case do not experience an asymptotic growth phase. Further, the resonance growth phenomenon found in incompressible unsteady shear turbulence is absent in the compressible case. Overall, the stabilizing influence of both unsteadiness and compressibility is compounded leading to suppression of all small perturbations. The underlying mechanisms are explained.

Document Details

Document Type
Pub Defense Publication
Publication Date
Dec 01, 2015
Source ID
10.1063/1.4937954

Entities

People

  • Rebecca L. Bertsch
  • Sharath S. Girimaji

Organizations

  • Air Force Office of Scientific Research
  • National Aeronautics and Space Administration
  • Texas A&M University

Tags

Readers

  • Control Systems Engineering.
  • Fluid Dynamics.
  • Plasma Physics / Magnetohydrodynamics