平流层飞艇热力学模型和上升过程仿真分析

建立了平流层飞艇的热力学控制模型,并采用该模型对飞艇的上升过程进行了仿真分析。分析表明,飞艇上升过程中的热力学和动态传热过程对飞艇的浮力和飞行控制有重要影响;飞艇上升过程中,为保持艇内外压差,需维持较大的空气出流量,艇内气体随外界压力降低膨胀做功,飞艇会处于较大的超冷状态,飞艇与外界大气的对流换热和日照条件下吸收太阳热辐射能量,可减轻飞艇的超冷状态;飞艇上升速率越快,艇内外气体温差越大,飞艇超冷状态越严重,净静升力降低越大。

Thermodynamic Model and Numerical Simulation of a Stratospheric Airship Take-off Process

A thermodynamic model of a stratospheric airship with convective and radiation heat transfer relation is proposed in this article.Numerical simulation on the airship take-off process was carried out based on this model.It shows that thermodynamic and heat transfer processes have significant influence on the static lift force and flight control of an airship.During take-off process,large air exit flow-rate should be maintained to achieve required pressure difference.The pressure of lifting gas and air inside the airship reduces rapidly.Thus the airship may in large "super cold" condition and the static lift force reduces significantly.Heat transfer between airship and outer atmosphere and absorption of solar radiation can alleviate the "super cold" condition during take-off process.The more rapidly an airship ascends,the more severely its "super cold" condition becomes,and the more significantly the net static lift force reduces.