Results of Parallel-Flow Stability Calculations Obtained by Time-Sharing Computations

Abstract

A series of programs for calculation of eigenvalues and eigenfunctions for parallel incompressible flow have been developed for use on the Massachusetts Institute of Technology time‐sharing computer system. The programs were designed building‐block fashion allowing a great variety of combinations of velocity profiles and boundary conditions (flexible walls, etc.) to be treated. Also, running instructions are built into the programs themselves and communicated to the user dialog‐fashion during the run making their use very simple for anyone with a minimum of prior instructions thus greatly facilitating numerical experimentation. The program system serves, in effect, as an extensive and rather complete set of tables of solutions for the problem area considered. Several examples are shown and discussed such as channel and boundary‐layer flows with and without inflection points, boundary layers over compliant surfaces, comparisons between viscous and inviscid calculations, and wave propagation constants for a turbulent boundary layer. The efficiency of the particular method employed for supressing numerical instability is also discussed.