Ad
related to: underexpanded vs overexpanded nozzle
Search results
Results From The WOW.Com Content Network
If a nozzle is under- or overexpanded, then loss of efficiency occurs relative to an ideal nozzle. Grossly overexpanded nozzles have improved efficiency relative to an underexpanded nozzle (though are still less efficient than a nozzle with the ideal expansion ratio), however the exhaust jet is unstable. [1]
Altitude compensating nozzles address this loss of efficiency by changing the shape or volume of the rocket nozzle as the rocket climbs through the atmosphere. There are a wide variety of designs that achieve this goal, with the aerospike being perhaps the most studied among them. Aerospike engine; Plug nozzle; Expanding nozzle
The expanding nozzle is a type of rocket nozzle that, unlike traditional designs, maintains its efficiency at a wide range of altitudes. It is a member of the class of altitude compensating nozzles, a class that also includes the plug nozzle and aerospike. While the expanding nozzle is the least technically advanced and simplest to understand ...
While research into this nozzle continues, it could be used before all its advantages are developed. As an upper stage, where it would be used in a low ambient pressure/vacuum environment specifically in closed wake mode, an E-D nozzle would offer weight reductions, length reductions and a potential increase to the specific impulse over bell nozzles (depending on engine cycle) allowing ...
A de Laval nozzle (or convergent-divergent nozzle, CD nozzle or con-di nozzle) is a tube which is pinched in the middle, with a rapid convergence and gradual divergence. It is used to accelerate a compressible fluid to supersonic speeds in the axial (thrust) direction, by converting the thermal energy of the flow into kinetic energy .
It uses carbon composite materials and uses the same basic design for both stages. The plug-cluster aerospike engine puts out 90,000 pounds-force (400 kN) of thrust. The engine has a bell-shaped nozzle that has been cut in half, then stretched to form a ring with the half-nozzle now forming the profile of a plug. [8]
A nozzle extension is an extension of the nozzle of a reaction/rocket engine. The application of nozzle extensions improves the efficiency of rocket engines in vacuum ...
This is referred as overexpanded flow because in this case the pressure at the nozzle exit is lower than that in the ambient (the back pressure)- i.e. the flow has been expanded by the nozzle too much. [13] A further lowering of the back pressure changes and weakens the wave pattern in the jet.