Non-uniform velocity effect in a constant-area ejector without a diffuser

A determinate mathematical compressible-flow model, with different velocity profiles applicable in the relevant governing equations for a constant-area ejector without diffuser, was formulated. The twelve governing equations were reduced to a single implicit equation for the primary variable P0. The flow parameters of the primary, secondary and mixed flow can be calculated directly using the solved value of P0. Some empirical data for an existing system with a duct area ratio of 0·9643 of the secondary flow to the mixed flow were compared with predicted values. The comparisons show that the one-dimensional compressible-flow analysis gives a fairly good agreement. A shock-like jump phenomenon of the ejector flow was observed experimentally in a previous paper and was also found theoretically in the present study. The performances of a stationary ejector, with different inlet area ratios, and secondary-to-primary stagnation pressure ratios are discussed.