Acoustic response of turbulent reacting recirculatory flows
Abstract
Experiment and analysis are reported upon concerning two dimensional plane turbulent cold flow behind a backward facing step which is acoustically forced. Numerically, the axisymmetric configuration was also examined. At issue is the interaction between vorticity and acoustics. It is shown experimentally that a lock-in between the shear layer behind the step and the acoustic potential field can occur at distinct frequencies. Furthermore, there is a significant alteration of the potential field when this occurs. In addition, the lock-in is removed when the recirculation zone is removed by a wind tunnel insert. Full numerical Navier-Stokes solution of the problem has shown that this phenomena is heavily dependent upon the boundary conditions of the problem and shows that inviscid treatments of the problem are likely to give misleading results.
- Publication:
-
The 23rd JANNAF Combustion Meeting, Volume 1
- Pub Date:
- October 1986
- Bibcode:
- 1986jann.conf..485D
- Keywords:
-
- Backward Facing Steps;
- Mathematical Models;
- Navier-Stokes Equation;
- Ramjet Engines;
- Recirculative Fluid Flow;
- Vortices;
- Boundary Conditions;
- Boundary Value Problems;
- Channel Flow;
- Flame Stability;
- Flow Distribution;
- Acoustics