The Statistical Analysis of Gas Ejectors in High Altitude Test Facilities for Space Motors

In the present research about 50 high altitude test facilities (HATFs) in the world and ejectors of them have been analyzed. Practical information such as type of the ejector, operating fluid, procedure of fluid generation, operating pressure and temperature, Thermal protection and costs of construction and operation can be useful in developing space industries. The present study shows that in 87% of the 50 HATFs, central ejectors and in 76% of them water steam have been used. Water spray cooling is often used to provide thermal protection for ejectors. Based on the available references, the water mass flow rate for cooling system is in the range of 1.8 to 3.9 times of the mass flow rate of exhaust gases of the engines with thrust in the range of 0.11 to 204 kN. To produce water steam, the HATFs for solid and liquid fuel engines frequently employ the steam accumulators and steam generators, respectively.