Comprehensive Gas Ejector Model

摘要

A comprehensive one-dimensional analytical model has been developed for gas ejector design and analysis. Unlike existing models, no assumptions have been made to simplify the momentum conservation equation for the ejector mixing chamber (that is, constant-pressure and constant-area models). Instead, the new model solves the momentum equation, which results in improved accuracy and versatility over existing models. Previous models can be derived from the new model as particular cases. These derivations provide new understanding of the relationships between the constant-pressure and constant-area one-dimensional ejector analytical models. The new model extends to the problems left unsolved by existing models and is efficient in analyzing off-design operating conditions, such as the shock that occurs in the primary stream. From the new model, the limitations on ejector design and operation are also recognized.