关键词: 气泡;断裂;热射流;等温射流

Abstract: To study the variation of bubble in underwater high-speed gas jet,the coupling numerical value results for the dynamic high-speed isothermal jet and thermal gas jet flow field was abtained by means of Volume of Fluids model.The effect of vaporization on the flow in the bubble is considered in terms of thermal jet.The formation,developing,fracture and fusion of bubble are properly simulated.The results show some regular patterns with the variation of the parameters such as pressure and Mach number in the bubble.It is found that with the same inlet pressure,the thermal jet flow displays events occurring on smaller spatial scales than observed in the isothermal jet flow.With the development of bubbles,it appears necking,and even fracture.Bubble fracture or not depends on the pressure difference between inside and outside of the location of bubble necking.The necking and fracture of bubble is an important factor in the pressure pulsation.They also determine the location and size of the peak press-ure.The more bubbles fracture location near the nozzle exit,the greater the peak pressure.The size of peak pressure affects the characteristics of wake field of rocket motor.

Key words: Bubble;Rupture;Thermal jet;Isothermal jet