Effects of Exhaust Channel Flow Loss on Underground Silo Ejection Performance

Aiming at the design of underground silo ejectors, a description method of silo ejectors considering exhaust channel flow loss was proposed, which based on the theory of ejector function and compressible fluid dynamics in pipe. Combined with the ideal ejector mathematical model, the basic ejector mathematical model considering the flow loss of the exhaust channel and the limit ejector mathematical model were established respectively. Based on the two mathematical models, introducing the ejector function and the static pressure matching function considering the exhaust channel flow loss, effects of total engine pressure, mixing chamber diameter and total impulse resistance coefficient on the underground silo injection performance were studied. And the variation law of total impulse resistance coefficient along with the exhaust channel loss coefficient and turning angle was analyzed. Three conclusions can be obtained from the simulation results. Higher engine total pressure and lower diameter of the mixing chamber cannot acquire lower inlet pressure of the mixture chamber. Lower total impulse resistance coefficient can acquire lower inlet pressure of the mixture chamber. The total impulse resistance coefficient increases when the exhaust channel loss coefficient increases and the exhaust channel turning angle decreases. © 2022, Editorial Department of Journal of Propulsion Technology. All right reserved.