Numerical Solution of Laminar and Turbulent Boundary Layer Equations Including Transition, and Experimenmtal Study of a Flat Plate with a Blunt Fin at Incidence

摘要

This study combines the techniques of computational fluid dynamics and experimentation. An unsteady laminar boundary layer code was shown to be more efficient when modified to solve the momentum and energy equations using Thomas' algorithm instead of optimized successive over relaxation (SOR). A steady eddy viscosity turbulence model was then added to the code: two models for the inner region, Van Driest and Chapman, and two models for the outer region, a mixing length and Clauser were used. The computer code was verified against theoretical and experimental data from the literature. The code shows excellent results for laminar flow and each of the models showed very good agreement with turbulent experimental data. The experimental study was conducted in a Mach 6 blowdown wind tunnel. Oil flow, sublimation, liquid crystals, and thin film gages were used to examine the flow structure and heat transfer on a flat plate. The heat transfer rates from these gages were lower than from the liquid crystals. The viscid inviscid interaction flow region of flow past a blunt fin mounted on the flat plate was examined using the same flow visualization methods and possible flow interaction models are presented. Striation heating appeared when the fin incidence was 40 deg. and the sweep was 60 or 75 deg. The numerical and experimental techniques of this study were then merged. The heat transfer results from the flat plate experiment were compared with results from the computer code and were found to be in good agreement. (Thesis) (Author)