COMPARISON OF CERTAIN EMPIRICAL PARAMETERS FOR CONICAL NOZZLES AND DIFFUSERS WITH THE RESULTS OF A ONE-DIMENSIONAL COMBINED-CHANGE ANALYTICAL MODEL

摘要

Traditional analysis of one-dimensional compressible flow in conical nozzles and diffusers relies on empirical values of parameters such as nozzle and diffuser discharge coefficients. New developments in the field of computational fluid dynamics enable a thorough examination of the flow field in all shapes of nozzles and diffusers. However, there is still a need for the simpler analysis that a one-dimensional approach provides. A new one-dimensional combined-change analytical model provides the opportunity to compare the empirical efficiencies and discharge coefficients with more usual flow parameters such as length, diameter, and friction coefficient. This paper is restricted to conical geometry because the analytical model assumes a thermodynamic path that is consistent with this geometry. In addition, the analytical model assumes the steady flow of a perfect gas.