Development of vacuum plume effects ground simulation experimental system key technology

The development process of vacuum plume effects ground simulation test facilities from high altitude simulation test facilities to vacuum test system was described. The limitation of ejector principle and the applicability of cryogenic condensation technology were described. The American CHAFF-4(the collaborative high altitude flow facility-IV) facility, German STG(Simulationsanlage für Treibstrahlenin Göttingen) facility and China's first large-scale vacuum plume effects ground simulation experimental system-PES (the plume effects experimental system)facility were introduced, all of which were constructed based on the low temperature condensation technology. Details of the initial simulation investigation of PES's built-in LHe cryogenic pumping were presented along with the results from a direct simulation of Monte Carlo(DSMC). The results demonstrate that, with or without the plume cryogenic pumping, at 2 g/s stage thruster working condition, the built-in liquid helium cryogenic pumping can meet the condition that the environment of the back pressure, in the region of φ4 m×5 m, is less than 10 ^-3 Pa, and plume cryogenic pumping can effectively prevent the compression wave from diffusion to the nozzle direction.