Lifetime cycle testing of model nozzles made of a carbon–carbon composite material in an oxygen-hydrogen liquid-propellant rocket motor

Results of a series of firing tests of two model nozzles made of a carbon–carbon composite material are reported. This material can be used to fabricate nozzles for a large-scale liquid-propellant rocket motor. The tests are performed in an experimental setup operating on oxygen and hydrogen. It is shown that the thermochemical loads on the nozzle material in model tests are greater than those under real conditions. The temperature of the outer surface of the nozzle is measured in each experiment by thermocouples and an infrared imager. The level of linear erosion of the wall material during the entire test period is determined. It is demonstrated that the results of firing tests can be used for estimating the operation performance of a large-size motor. A simple analytical dependence is proposed for recalculating the results of model tests on material erosion to full-scale conditions.