Numerical investigation on performance of the adjustable ejector.

A numerical study on the performance of an adjustable ejector was presented. An axial spindle extending into the nozzle was used to change the throat area of the nozzle to make the ejector adjustable. The re-normalization group (RNG) k-epsilon model reconciled better with experimental measurements than other two turbulence models and was utilized to simulate the flow inside the adjustable ejector. The numerical results indicated that, at the same certain motive and suction operating conditions, the adjustable ejector had higher entrainment ratio and lower discharge pressure. The existence of spindle diminishes the nozzle throat cross-sectional area; as a result, the motive flow rate was reduced. These characteristics of the adjustable ejector provided potential for more economical design and operation. [ABSTRACT FROM AUTHOR]