The potential of supersonic combustion ramjets is explored from the point of view of ideal frictionless, shock free operation and the effect of actual losses due to shocks, skin friction, nozzle underexpansion, divergence and non equilibrium chemistry. The speed range explored in these calculations is from Mach 8 to Mach 24, which is orbital insertion speed at most altitudes of interest. A surprising result is that combustor skin friction and heating can have a very small effect on performance. This is true because, in the case of the constant area combustor used in the study, the skin friction force is partly compensated for by the momentum increase in the heated fuel and fuel rich operation improves nozzle performance. The nozzle shows about the same effect as the inlet, but this is partly because nozzle underexpansion losses are increased with increasing inlet losses and inlet losses from ideal include these changes in nozzle losses. Methods of limiting losses are discussed. With the level that is achievable in a well designed engine, a fuel fraction close to 50 % can be calculated to reach orbit insertion speed in an orbital airplane.
The potential of supersonic combustion ramjets
Das Potential der Überschallstaustrahltriebwerke
1995
7 Seiten, 15 Bilder
Conference paper
English
The Potential of Supersonic Combustion Ramjets
British Library Conference Proceedings | 1995
|Application of supersonic combustion to ramjets
Engineering Index Backfile | 1966
|Application of Supersonic Combustion to Ramjets
Emerald Group Publishing | 1966
|