Experimental Measurements of an Expansion Deflection Nozzle in Open Wake Mode

From The Space Library

Jump to: navigation, search

Author - N.V. Taylor et al

Co-Author(s) - N. V. Taylor; T. Sato

JBIS Volume # - 60

Page # - 377-386

Year - 2007

Keywords - Expansion deflection, nozzles, rocket propulsion, experimental aerodynamics

JBIS Reference Code # - 2007.60.377

Number of Pages - 10

[edit] Abstract

Expansion Deflection nozzles present an attractive proposition as a replacement for conventional nozzles on launch vehicles, due to their reduced length, and altitude compensating capability. However, it has long been speculated that they suffer in the latter regard due to aspiration of the low speed flow region inside the nozzle by the supersonic jet surrounding it. This effect is investigated in this paper by direct experimental measurement of base pressures, and found to have little effect on the base pressure of the nozzle within the range of operating conditions investigated. Wall pressures were also used to calculate the efficiency of the altitude compensation within the nozzle, which was found to be between 87 and 100% for the three operating pressure ratios examined. This represents a significant improvement over conventional nozzle performance, and further conformation that wake pressures are indeed close to ambient.


To BUY this paper click here




JBIS is © 1934-2013 British Interplanetary Society -