The multi-phase flow models coupling with projectile motion and vaporization were established respectively under different conditions of throat diameter ratio. What’s more

the influence of throat diameter ratio on gas-steam ejection flow field

ejection device load and interior ballistics was studied. Results showed that increasing or decreasing the throat diameter ratio within a certain range led to the deterioration of ejection device flow field and launch stability. When the throat diameter ratio increased too large

the spray pressure difference meeting the working conditions could not be established. When the throat diameter ratio was too small

the shock wave upward movement eventually led to abnormity of the gas generator. When the throat diameter ratio was 1.46

the pressure difference of tail cover was the smallest and the launch stability was the best. The maximum temperature of launch tube was controlled within the design value of 800K

and the interior ballistic parameters could satisfy the design requirements.