CTS-0238390 M. MARTIN PRINCETON UNIVERSITY
The proposed research is focused on developing a basic understanding of hypersonic transitional and turbulent flows. Previous turbulence models for hypersonic applications have been calibrated using direct numerical simulation data of incompressible flows or perfect gas wind tunnel data. Thus, the models that are used today do not represent the effects of high compressibility and temperature levels. Accordingly, this research will provide solutions for (1) improving our understanding of the fundamental physical mechanisms of transitional and turbulent hypersonic flows; (2) providing an accurate and detailed database of the flows of interest; and (3) using the gained understanding and database to develop physically-based scaling laws for the accurate prediction of these flows. The proposed configurations include transitional and turbulent boundary layers with and without adverse pressure gradient, as well as flow around axisymmetric and elliptical cross-section cones. The effects of free-stream disturbance, Mach number, and wall-temperature conditions will be studied for non-reacting and reacting conditions. A key feature of the simulations is the validation against experimental data at the exact same conditions. This research will have significant impact on a large number of technologically important applications related to hypersonic flight within and out of our atmosphere. Concurrently, education activities will address important and challenging engineering problems while fostering a dynamic learning environment. The goals of the education and outreach plan include: (1) integrating research and education via a modular scientific computing, data analysis, and database software infrastructure; (2) organizing outreach activities for talented students of under-represented groups in K-12, undergraduate and graduate levels; and (3) maintaining and building upon a current curriculum. A key planned activity is the integration of a computational infrastructure to solve and analyze fluid flow problems into the classroom and into the scientific community. Undergraduate and graduate students will use the infrastructure as part of their course materials. Other education and outreach activities include a summer course in hypersonic flight to promising high-school students from lower-income families. This will provide an opportunity for the students to participate in the academic and cultural life of Princeton University. In collaboration with the Prince-ton University Preparatory Program, twenty students will be selected from schools in the Trenton, Ewing and Princeton areas. For a period of three years these students will enroll in a week-long course sequence in hypersonic flight. In addition, summer internships will be offered to two students of under-represented groups.