热管内蒸发和凝结时工质会径向迁移,导致蒸汽流动特性与管流有很大不同。对热管内蒸汽流动的速度分布和压降特性进行了分析,比较了现有热管蒸汽压降的计算方法。同时考虑蒸汽流动时黏性力和惯性力的作用,提出了计算蒸汽流动速度和压降的改进方法,消除了前人方法应用范围的限制。利用此计算方法,蒸汽速度分布随径向雷诺数变化较大。与钠热管的数值模拟结果对比表明,此计算方法应用范围广,准确度较高。 When the heat pipe evaporates and condenses, the working fluid will migrate radially, resulting in very different steam flow characteristics from the pipe flow. The velocity distribution and pressure drop characteristics of the steam flow in the heat pipe were analyzed. The calculation method of the steam pressure drop in the heat pipe was compared. At the same time, considering the effect of viscous force and inertial force on steam flow, an improved method of calculating steam flow velocity and pressure drop is proposed, which eliminates the limitation of the application range of the previous methods. Using this method, the steam velocity distribution varies greatly with the radial Reynolds number. The results of numerical simulation with sodium heat pipe show that this method has a wide range of applications and high accuracy.