【摘要】 飞艇热控制是平流层飞艇应用中涉及的关键技术之一,而外部对流换热是平流层飞艇热控制的重要影响因素.为了准确预测飞艇换热,基于数值模拟,建立基于飞艇长径比的对流换热准则关系式,并与实验结果比较,发现其预测误差为±7%.与0°攻角换热相比,15°攻角时迎风面换热比背风面增大了10%左右,而总体换热增大7%.更多还原

【Abstract】 Thermal control is one of the key technologies involved in stratospheric airship applications,and convective heat transfer is an important factor in the thermal control of a stratospheric airship.In order to accurately predict the heat transfer of an airship,using the numerical method,an empirical correlation of Nu number as a function of Re,Pr and l/d(length to diameter ratio) was established.Compared with experimental data,the uncertainty of the empirical correlation is about ±7%.The effect of the attack angle of an airship on heat transfer performance was evaluated.It was found that the heat transfer at the windward side is 10% higher than that of the leeward side,while the average heat transfer of airship is 7% higher when the attack angle changes from 0° to 15°.更多还原