Research On Ejector-Mixer Aerodynamic Characteristics Of Round Nozzle With Tabs

Tabs were used in the two-flow exhaust mixer-ejector, which compose the mixing pumping system. It is a new kind of mixer-ejector, which is different from the lobed mixer-ejector. To make an inquiry into the internal and external mixing aerodynamics, research was made on this kind of mixer-ejector system by a series of experiments and computations.A series of experiments and computations on the pumping-mixing characteristics of tabbed-round nozzle with different tab geometrics and arrangements were conducted under cold or hot cases. Many experimental and computational data including temperature distributions, pressure distributions, thermal mixing efficiency and pumping coefficient were obtained. Based on these data, we got the basic disciplinarian. The results show that: this new kind of mixer-ejector by tabbed-round nozzle could enhance the pumping coefficient, change the aerodynamic characteristics of mixing flow, and make the pressure, velocity and temperature distributions more uniform at the outlet of mixing duct, which is benefit to reduce the infrared radiation. We still do a research on new kind of staggered arrangement tabs. The results show that it has a relatively low pumping coefficient but high thermal mixing efficiency. In general, the mixer-ejector aerodynamic characteristics of this new kind of tabbed-round nozzle is not so good as lobed nozzle, but considering the performance of its simple structure and light weight, it will still be a good choice in application.The present results could be helpful to optimize the model structure in the further research.