Analysis of the Combined Control Ability of Stratospheric Balloon Phase Change Gasbag and Auxiliary Gasbag

The stratospheric high-altitude balloon is an unpowered aircraft that relies on the lifting gas and is mainly affected by high-altitude thermal characteristics. In most cases, high-altitude balloons use a single gasbag structure, which is filled with the lifting gas to gain buoyancy and fly high in the air. Google added an air gasbag inside the main gasbag to improve auxiliary flight and achieved favorable flight results. The triple-gasbag aerostat is a single air gasbag that adds an air gasbag and a phase change gasbag,respectively, relying on the gas-liquid phase change system and air pump to adjust the size of the phase change gasbag and air gasbag. Through the analysis of stratospheric altitude direction dynamics and thermodynamic characteristics, a coupled mathematical model is established, and data simulation is carried out. In the control system, the combination of gas-liquid phase change and air exchange is used to analyze the influence of solar radiation on the pressure and height changes caused by the heating and cooling of the gasbag under different gas liquefaction rates, in order to avoid super-pressure and super-heat and maintain a stable flight state. At the same time, energy consumption needs to be considered to obtain the maximum control effect on the pressure difference, thereby achieving flight at an altitude of about 20km at mid or low latitudes.