Development status of the reusable high-performance engines with functionally graded materials

Abstract

The background of the development of the two kinds of reusable high-performance engine is described. One of these two is the regeneratively cooled 1200 N thrust engine composed of two kinds of ZrO 2/Ni functionally graded materials (FGMs) chambers. This engine is a promising candidate for the future Japanese orbiting maneuvering system (OMS) engine of the H-II orbiting plane (HOPE). The other one is the reaction control system (RCS) engine which may also be used compatibly with HOPE. Developed RCS chambers are made of carbon-fiber-reinforced carbon matrix (C/C) composites coated with SiC FGMs. In the first stage of the development of the ZrO 2/Ni FGMs chamber, durability tests using a ZrO 2 (24.5 vol%)/Ni (75.5 vol%) FGMs chamber were performed to inspect the damage of the thermal coating layer and to evaluate the engine performance after a total of 260 firing tests. In the second stage, a combustion chamber having a compositional profile of perfect ZrO 2/Ni FGMs was used in the high-altitude performance tests (HAPT). Firing tests for the C/C–SiC FGMs chamber developed in the first stage were performed at sea level. In this test series, microcracks and penetration of the combustion gases were observed especially at the surface of the nozzle throat section after 382 cycle tests. In the next stage of developing C/C–SiC FGMs chamber (expansion area ratio of 30:1), it was shown that coating with FGMs seemed to effectively prevent the delamination of the SiC coating after 693 cycles under the conditions of P c =1.0 MPa , MR=1.65 and with an injector film cooling rate of 17%, over a total firing time of 2000 s .