Abstract: A mathematical model of multi-nozzle ejector was established according to the mass conservation, energy conservation and momentum conservation, and a modification was achieved with the introduction of momentum correction coefficient and discharge coefficient. On this basis, linear coefficients used in the fluid network method were determined, then a system-level simulation model of multi-nozzle ejector was first developed with C# language on the fluid system simulation software of Flowmaster. The simulation and experimental results of the multi-nozzle ejector in an aircraft environmental control system shows that the entrainment ratio decreases with the increasing pressure ratio of primary and secondary flow. The relative error between the simulation and experimental values of primary mass flow rate, secondary mass flow rate and entrainment ratio are respectively 0.05%-2.74%、2.59%-6.64% and 1.20%-7.77%, which verifies the accuracy of the simulation model.

Key words: ejector, multi-nozzle, mathematical modeling, simulation model, fluid network