Исследование автоколебаний в импактных струях

A mechanism of self-oscillations in the impacting jets is investigated. The numerical simulation of the self-oscillations process in the underexpanded supersonic jet flowing on the plant limited obstacle is carried out. The creation of a adequate phenomena physical model is carried out by a transition from common to quotient method. Namely, the self-oscillations in the impacting jets is considered as a partial case of a vast range of problems about self-oscillations, arising when a non-homogeneous supersonic stream flowing an obstacle with separated zone beginning. The new working out phenomena physical model taking into account a hi-enthalpy gas flowing from periphery flow into the separated zone and the interaction of processes in the periphery flow and separated zone. The self-oscillations mechanism is connected with periodic flowing of hi-force gas from periphery flow into the separated zone and following gas outflow from it. The alternation of flow into and outflow phases is conditioned by the changing of separated zone dimensions. The increase of separated zone dimensions leads to a cessation gas flow into and beginning of gas outflow from the separated zone. The decrease of separated zone dimensions in the outflow phases following to what the periphery flow again falls on the obstacle blocking the gas outflow from the separated zone. Further process is repeated. Interaction of processes in the separated zone and in the periphery flow is showed mainly by a presence of rear waves associating to shock waves in the adjacent flow regions.