CMC Rocket Combustion Chamber with Effusion Cooling

Abstract

New propulsion systems play a key role for future space transportation systems (STS). While high efficiency with respect to specific impulse is mandatory aspects concerning system design (complexity, manufacturing, weight), operating aspects (reusability, maintenance, high reliability and safety) and cost reduction attract increasing attention. A significant step forward seems to be the application of high temperature usable ceramic matrix composites (CMC) within a cryogenic combustion chamber design. The approach is using a porous fibre ceramic inner combustion chamber liner. Operating temperatures of the CMC material lie far upper than 1800 • C. Nevertheless an appropriate cooling method has to be applied accompanied by temperatures of about 2700 • C running the combustion process. While the porous CMC is responsible for both thermal load absorption and the effusion cooling the mechanical load carrying structure consists on a carbon fibre reinforced plastic (CFRP) outer shell. Using both ring shaped ceramic combustion chamber segments on 1-10 MPa pressure levels and a complete ceramic thrust chamber design on 1 MPa pressure level samples demonstrated already the physical principles. The paper will give an overview of the current development status, whereby the experience achieved so far is very promising out looking to the general goals.

Transpiration Cooling Performance in LOX/Methane Liquid-Fuel Rocket Engines

“…Porosity values in this parametric analysis are consistent with those used in a recent test at the DLR, (Lampoldshausen German Aerospace Centre). 15 In this facility a carbon-carbon material has been tested with ≈ ε 20%. A pyrolysis process can obtain porosity of about 15%…”

“…Unfortunately test data of [15] could not be compared to predictions presented here, due to large differences in geometry, combustion chamber pressure and especially coolant utilized (hydrogen). Fig 20, 21 show how porosity (obtained with both strategies 1 and 2) can reduce t. In fact, t varies from 7 mm up to 31 mm, a substantial range, due to the porosity changing along the nozzle axis.…”

Investigation of Transpiration Cooling Performance in Lox/Methane Liquid Rocket Engines

“…Porosity values in this parametric analysis are consistent with those used in a recent test at the DLR, (Lampoldshausen German Aerospace Centre). 15 In this facility a carbon-carbon material has been tested with ≈ ε 20%. A pyrolysis process can obtain porosity of about 15% and lower, by a process allowing porosity to be varied with high reliability and precision.…”

“…Unfortunately test data of [15] could not be compared to predictions presented here, due to large differences in geometry, combustion chamber pressure and especially coolant utilized (hydrogen).…”