Ceramic Journal Bearings in Cryogenic Turbo-pumps

摘要

The availability of components built in CMC technology forms in major areas a prerequisite for the realisation of future reusable launcher engines. Apart from the efforts to introduce CMC components in the hot areas of the engine like nozzles and thrust chambers there exists an important optimisation potential in the engines through the use of CMC components in (cryogenic) turbo-pumps. By replacement of the ball bearings in the pumps by journal bearings, a significantly higher lifetime can be obtained and the inherent limitation of the turning speed of the pumps can be widely extended. The CMC journal bearings of MAN have proven their quality and reliability in numerous applications in industrial pumps. Based on this experience a research program was initiated by DLR and funded by means of the BMBF and MAN to investigate the use of this bearing type under the conditions of a cryogenic turbo-pump. Major results are presented in this paper.