Numerical investigation on thrust characteristics of an annular expansion–deflection nozzle

The thrust characteristics of a large-expansion-ratio annular expansion–deflection (ED) nozzle are investigated based on detailed flow pattern simulations. purpose is to build bridge between the internal and performance. present work traces parameters along typical streamlines demonstrate pattern, partitions exit plane its features evaluate contributions each coefficient contributor in different sub-areas, monitors parameter distributions at 22 pressure ratios interpret developing histories coefficients. simulations show that shocks generated open wake mode both inevitable indispensable, while closed contribute negatively Three basic requests for designing high-performance ED clarified, which ensure high-quality expansion throat, smooth out reflected shock mode, diminish strong near-wall mode. An interesting counter-intuitive phenomenon, namely, existence not only consumes ability exhaust do but also improves overall performance, explained. This because deflects lateral-going axial direction. When this disappears, sudden drop history takes place.