Application Of Shock Tubes To Transonic Airfoil Testing At High Reynolds Number

The linearized attenuation theory of NACA Technical Note 3375 is modified in the following manner: (a) an unsteady compressible local skin-friction coefficient is employed rather than the equivalent steady-flow incompressible coefficient; (b) a nonlinear approach is used to permit application of the theory to large attenuations; and (c) transition effects are considered. Curves are presented for predicting attenuation for shock pressure ratios up to 20 and a range of shock-tube Reynolds numbers. Comparison of theory and experimental data for shock wave strengths between 1.5 and 10 over a wide range of Reynolds numbers shows good agreement with the nonlinear theory evaluated for a transition Reynolds nuniber of 2.5 million.

The research work of the collaborative research center SFB401 Flow Modulation and Fluid-Structure Interaction at Airplane Wings at the Rheinisch-Westfälische Technische Hochschule (RWTH) Aachen, which is reported in this book, was pos sible due to the financial support of the Deutsche Forschungsgemeinschaft (DFG). The proposal has been approved after evaluation by the referees of DFG selected from other universities and industry, which is gratefully acknowledged. The work is still in progress and now approved to continue until the end of year 2005. More than 50 scientists from universities of the United States, Russia, France, Italy, Japan, Great Britain, Sweden, Netherlands, Switzerland, Austria and research orga nizations NASA, ONERA, NLR, DLR could be invited and have visited the research center, gave seminars on their research on related topics and some of them stayed longer for joined work. Besides its scientific value, also the importance of the pro gram for scientific educa tion becomes evident by looking at the numbers of completed theses, which are up to now about 15 doctoral theses, 40 diploma theses and 70 study theses. The authors of this book acknowledge the valuable support coming from all these persons and institutions. They are especially grateful to the referees having reviewed this work, A. Cohen (Universite Pierre et Marie Curie), J. Cooper (Manchester School of Engineering), W. Devenport (Virginia Tech.), M. Drela (MIT), F. Gern (Avionics Specialties Inc.), A. Griewank (TU Dresden), H. Hönlinger (DLR), P.