This report summarizes research conducted during the past year whose aim is to develop and test an accurate and efficient method for describing boundary-layer development in the transition region. A low-Reynolds-number version of the Wilcox k-w model has been postulated and tested against experimental data for 10 fully turbulent boundary layers and for more than 20 transitional cases. Overall discrepancies between theory and experiment are smaller than those for simpler correlations designed for use with algebraic turbulence models. Singular perturbation analysis of the compressible viscous sublayer and defect layer has been initiated with some interesting preliminary results. Some progress has been made toward eliminating the k-w model's sensitivity to the freestream boundary condition on w ... Transition, Turbulence modeling, Hypersonics, Computational fluid dynamics.

Research conducted during the past three and a half years aimed at developing and testing a turbulence/transition model applicable to high-speed turbulent flows is summarized. The first two years of the project focused on fully turbulent flows, while emphasis shifted to boundary-layer development in the transition region during the final year and a half. A brief summary of research accomplished during the first three years is included and publications that describe research results in greater detail are cited. Research conducted during the final six months of the period of performance is summarized. The primary results of the last six months of the project are elimination of the k-omega model's sensitivity to the freestream value of omega and development of a method for triggering transition at a specified location, independent of the freestream turbulence level. Wilcox, David C. Unspecified Center DAAL03-89-C-0032; NASA ORDER L-54880-C; RTOP 505-59-50-01...