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Development of a three-dimensional pse code for compressible flows: stability of three-dimensional compressible boundary layers
| Content Provider | NASA Technical Reports Server (NTRS) |
|---|---|
| Author | Balakumar, P. Jeyasingham, Samarasingham |
| Copyright Year | 1999 |
| Description | A program is developed to investigate the linear stability of three-dimensional compressible boundary layer flows over bodies of revolutions. The problem is formulated as a two dimensional (2D) eigenvalue problem incorporating the meanflow variations in the normal and azimuthal directions. Normal mode solutions are sought in the whole plane rather than in a line normal to the wall as is done in the classical one dimensional (1D) stability theory. The stability characteristics of a supersonic boundary layer over a sharp cone with 50 half-angle at 2 degrees angle of attack is investigated. The 1D eigenvalue computations showed that the most amplified disturbances occur around x(sub 2) = 90 degrees and the azimuthal mode number for the most amplified disturbances range between m = -30 to -40. The frequencies of the most amplified waves are smaller in the middle region where the crossflow dominates the instability than the most amplified frequencies near the windward and leeward planes. The 2D eigenvalue computations showed that due to the variations in the azimuthal direction, the eigenmodes are clustered into isolated confined regions. For some eigenvalues, the eigenfunctions are clustered in two regions. Due to the nonparallel effect in the azimuthal direction, the eigenmodes are clustered into isolated confined regions. For some eigenvalues, the eigenfunctions are clustered in two regions. Due to the nonparallel effect in the azimuthal direction, the most amplified disturbances are shifted to 120 degrees compared to 90 degrees for the parallel theory. It is also observed that the nonparallel amplification rates are smaller than that is obtained from the parallel theory. |
| File Size | 7572690 |
| Page Count | 199 |
| File Format | |
| Alternate Webpage(s) | http://archive.org/details/NASA_NTRS_Archive_19990028363 |
| Archival Resource Key | ark:/13960/t8vb3323x |
| Language | English |
| Publisher Date | 1999-02-01 |
| Access Restriction | Open |
| Subject Keyword | Fluid Mechanics And Heat Transfer Computational Fluid Dynamics Runge-kutta Method Compressible Boundary Layer Turbulent Boundary Layer Three Dimensional Boundary Layer Supersonic Boundary Layers Compressible Fluids Slender Cones Amplification Navier-stokes Equation Two Dimensional Boundary Layer Azimuth Three Dimensional Flow Tollmien-schlichting Waves Reynolds Averaging Eigenvalues Inviscid Flow Viscous Flow Ntrs Nasa Technical Reports Server (ntrs) Nasa Technical Reports Server Aerodynamics Aircraft Aerospace Engineering Aerospace Aeronautic Space Science |
| Content Type | Text |
| Resource Type | Thesis |
