Effect of density gradients in confined supersonic shear layers. Part 2: 3D modes
Abstract
The effect of basic flow density gradients on the supersonic wall modes were investigated in Part 1 of this analysis. In that investigation only the 2D modes were studied. Tam and Hu investigated the 3D modes in a confined vortex sheet and reported that the first 2D Class A mode (A01) had the highest growth rate compared to all other 2D and 3D modes present in the vortex sheet for that particular set of flow patterns. They also showed that this result also held true for finite thickness shear layers with delta(sub w) less than 0.125. For free shear layers, Sandham and Reynolds showed that the 3D KH mode became the dominant mode for M(sub c) greater than 0.6. Jackson and Grosch investigated the effect of crossflow and obliqueness on the slow and fast odes present in a M(sub c) greater than 1 environment and showed that for certain combination of crossflow and wave angles the growth rates could be increased by up to a factor of 2 with respect to the 2D case. The case studied here is a confined shear layer shown in Part 1. All solution procedures and basic low profiles are the same as in Part 1. The effect of density gradients on the 3D modes present in the density ratios considered in Part 1 are investigated.
 Publication:

NASA STI/Recon Technical Report N
 Pub Date:
 November 1994
 Bibcode:
 1994STIN...9524413P
 Keywords:

 Acoustic Properties;
 Combustion Chambers;
 Cross Flow;
 Density (Mass/Volume);
 Mathematical Models;
 Modes (Standing Waves);
 Shear Layers;
 Supersonic Combustion;
 Three Dimensional Motion;
 Vortex Sheets;
 Boundary Conditions;
 Flow Distribution;
 Mach Number;
 Thickness;
 Fluid Mechanics and Heat Transfer