关键词: 发动机排气;超音速射流;自由射流;流动分布;工程计算

Abstract: n engineering calculation method for underexpanded supersonic rocket exhaust ispresented in .this paper. Flow variables in three sections (near-field,primary section of the exhaust andfar-field) are evaluated by using the quasi-one-dimensional isentropic flow model, the modified momentum-averaged behaviour model and the self-preserving model respectively. The method suggestedin this paper can be applied to calculated the boundary of a jet, the velocity and temperature distributions in primary section and in far-field of the exhaust flow field. COmpared with momentum-averagedbehaviour model, this method is more reasonable in dealing with the effect of Mach-disc and oscillating decline in supersonic core in primary section.

Key words: Engine exhaust;Supersonic jet flow;Free jet;Flow distributiion;Engineeringcomputation