Ascent Characteristic Study For Stratospheric Airship With Dynamic And Thermodynamic Coupling Model

In recent years, stratospheric airship reflects the great application value, and it affects people’s attention. Stratospheric airship usually operates at stratospheric atmosphere and can ensure long endurance at specific area. It has greater load capacity, strong survival ability, lower cost and so on. Stratospheric airship can provide specific area monitoring, communication and regional warning.Stratospheric airship ascent is more complicated. During the ascent, the external atmospheric environment changes greatly. Changes in the external environment affect the force of stratospheric airship and the heat exchange with the external environment. Therefore, it should consider dynamic and thermodynamic model to study the stratospheric airship ascent trajectory. There are three aspects researched in this paper:Firstly, the dynamic and thermodynamic model of stratospheric airship ascent is established. The dynamic model reflects the force of stratospheric airship ascent, and the thermodynamic reflects that solar radiation, infrared radiation and convection heat transfer impact stratospheric airship.Secondly, based on stratospheric airship ascent model, the properties of stratosphere airship ascent are researched by considering the different thermodynamic model, changing departure time, changing the heat capacity and direct solar radiation absorption rate of envelope. It shows that considering the complex thermodynamic model, the temperature of envelope and gas drops obviously, and the supercooling phenomenon is more serious. The ascent time is longer. Changing the departure time, it finds that direct solar radiation has a great influence on stratosphere airship ascent. Changing the properties of envelope finds that it plays an important role during the ascent, and selecting envelope is a key factor.Thirdly, the optimal trajectory for ascent is studied based on dynamics and thermodynamic model of stratospheric airship, the shortest ascent time index and the Gauss pseudospectral method.