Theoretical investigation of the combined flow of a two-dimensional,high-pressure stream and a one-dimensional,low-pressure stream of ideal gas in ejector nozzles

On the basis of [1] an improved method was developed which, within the framework of the model of an ideal gas, allows one to calculate the flow in ejector nozzles without a limit on the coefficient of ejection. During the development of the method it was established, on the basis of a preliminary analysis, that the difference equations which approximate the differential equations of the flow of coaxial streams in an ejector nozzle (high-pressure and low-pressure streams, treated in two-dimensional and one-dimensional approximations, respectively) have a singular point. Owing to the finiteness of the integration step the position of this singular point differs in the general case from the position of the singular point for the differential equations describing the flow under investigation. This difference is larger the smaller the coefficient of ejection. Now allowing for this fact in the existing methods of calculation in an analogous formulation [1–4] limits the possibilities of all these methods, as a rule, to cases of relatively large coefficients of ejection.Translated from Izvestiya Akademii Nauk SSSR, Mekhanika Zhidkosti i Gaza, No. 6, pp. 110–116, November–December, 1978.The authors thank A. N. Kraiko for useful discussions and attention to the work.