Shroud and Ejector Augmenters for Subsonic Propulsion and Power Systems

Abstract

where power is either added (e.g., for propulsion) or extracted (e.g., wind/water turbines.) The formulation is first principles based, free of empiricisms, overcomes past formulation limitations, and uncovers heretofore unknown high performance potential for such systems. For shrouded props, these new control-volume based predictions are shown to agree well with both independent experimental and computational data, as well as other analytical and empirical models. Solutions generally involve simple polynomials with a single input parameter that is easily determined from the aerodynamic performance of the empty shroud. This formulation provides new correlation parameters, plus greatly simplifies design optimization studies by decoupling the shroud and ejector design effort from that of the prop design.