1Ryerson Polytechnic University, Toronto, Ontario, Canada
2Tohoku University, Sendai 980, Japan
The paper deals with hypersonic axisymmetrical internal flows of a special type. Using conical flow theory we have constructed the particular internal flow surface which produces a straight incident conical shock that focuses on the axis of symmetry.
The shock wave flows under consideration possesses some interesting features to be taken into account when constructing a suitable numerical simulation technique. First of all, not only steady-state solutions (if they exist at all) are of interest but transition processes starting from an initial condition as well. Secondly, it turns out that, along with proper localization of discontinuities, high resolution of smooth conical flow area (which may be quite narrow under certain conditions) behind the incident conical shock is required. Finally, shock wave/axis-of-symmetry interactions may result in ``microscopic'', barely detectable Mach stems.
An adaptive unstructured Euler code is employed for computations. The code is based on triangular unstructured grids, the classical h-refinement technique, a second-order non-oscillatory Godunov-type scheme and an efficient data structures tailored differently for scalar and vector processing. For verification of the code and interpretation of obtained results experimental data \forcenl (schlieren photos) and theoretical distributions of gasdynamic parameters are used.
The code is applied for computations of conical shocks with different incident angles aiming to examine weak shock wave reflections at the axis of symmetry. Some interesting preliminary results have been already obtained and will be refined by the time of the Symposium.