Cooling of rocket plume using aqueous jets during launching

Abstract

With an increase in rocket motor thrust, the thermal loads on the launch platform by the impingement exhaust jet are significantly increased, this poses serious safety risks to rocket launch. Therefore, a water cooling system should be designed to improve the thermal environment. In this study, the cooling effects of a water spray system with different injection velocities were analyzed through numerical simulation of high precision, and the afterburning effect of the exhaust gas was also considered to improve the calculation accuracy. The results showed that afterburning primarily occurred in the mixing layer, leading to a larger high-temperature region in the impingement plate. The water cooling system realized thermal protection for the launch platform, which was achieved by decreasing the temperature and velocity of impingement jet. With an increase in the aqueous jet velocity, a more significant cooling effect of the water spray system was obtained. However, the guiding performance of the deflector was decreased owing to the large amount of water vapor formed in the channel. It is suggested that the water spray system design should adopt an aqueous jet velocity of 20 m/s as a parameter after considering the cooling effect and guiding performance of the deflector.

Keywords

• thermal environment
• aqueous jet velocity
• gas–liquid two-phase flow
• afterburning effect
• guiding performance