We studied the dynamics of motion and energy transfer in supersonic flow in the base region. It is shown in the article that the current in the base region largely depends on the boundary layer structure in the area between the trailing edge and the sticking point on the centerline, where the boundary layer cut out from the rear edge converges. The study of the effect of gas mass injection into the base region from the body surface and the bottom as well as heat transfer in the bottom region is included. The resulting solution of the problem of the middle wake for axisymmetric body without considering recirculation at a limited distance from the stern has been obtained.
Sidnyaev N., Gordeeva N. Investigation of the energy and mass transfer influence on the wake flow of supersonic conical models. Маthematical Modeling and Coтputational Methods, 2015, №1 (5), pp. 31-49
The article presents the theoretical analysis of the long-period (phugoid) aircraft oscillations, which has a lifting force and performs a flight at hypersonic speeds in any atmosphere. Oscillations are caused by mutual transition of kinetic energy into potential energy during the flight along the path having an oscillatory character and being determined primarily by controlled longitudinal zero momentum in steady flight. The study shows that with the speed approximating to the first cosmic speed, the decrease in gravity at height dominates the decrease in density of the atmosphere, so that with increasing speed the period of phugoid oscillations tends asymptotically to the corresponding period of the satellite. During the research there were obtained analytical expressions for the short-period oscillations or vibrations at the angle of attack. The study demonstrates that these expressions, as well as the expressions for the long-period oscillations are in good agreement with numerical solutions.
Sidnyaev N., Glushkov P. Long-period oscillations of aircraft at hypersonic speeds. Маthematical Modeling and Coтputational Methods, 2014, №1 (1), pp. 99-114