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Study on the internal surface charging of H2/O2 engine nozzles

The charging caused by charged particles in the nozzle can disadvantage the aircraft while the H2/O2 rocket engine is in operation. Based on the kinetic theory of gases, this paper makes use of the Maxwell velocity distribution function of the particles to formulate a general equation of the internal surface charging electrical potential of the H2/O2 rocket engine nozzle. Factors such as the mass, temperature and density of the charged particles and the secondary electronic emission yield of the internal surface materials of the nozzle are considered hypothetically. The surface charging electric potential of varied cases is analyzed and the charging law is summarized.