摘要: A series of instrumented engineering tests is described in which a 'channel flow' chemical vapor deposition furnace was used to prepare pyrolytic graphite/silicon carbide (PG/SiC) codeposited material for rocket-nozzle application... 展开 A series of instrumented engineering tests is described in which a 'channel flow' chemical vapor deposition furnace was used to prepare pyrolytic graphite/silicon carbide (PG/SiC) codeposited material for rocket-nozzle applications. The nozzle section and a water cooled center body formed a vertical annular flow passage for the coating gases. The nozzle section was inductively heated and was coated on the i.d. only. Well-mixed process gas entered the flow annulus with uniform velocity, temperature, and species concentrations from a plenum below the heated substrate. The flow could be either laminar or turbulent, but did not contain recirculating regions. An analytical model of the furnace and deposition process was developed to simulate the heat transfer in the solid components and the flow, chemical kinetics, and heat and mass transport associated with the process gas. Model predictions and test results on temperatures and PG/SiC deposition rates agreed very well. The coating microstructure and inferred quality were characterized by metallography and correlated with the process variables. The report includes detailed descriptions of the furnace, instrumentation, and test procedures in addition to plots of all reduced data. (Author) 收起