微重力下液氢流动沸腾的气泡脱离特性  

Bubble departure characteristics during liquid hydrogen flow boiling under microgravity

作　　者：郑尧 常华伟[2] 陈虹 舒水明[2] ZHENG Yao;CHANG Huawei;CHEN Hong;SHU Shuiming(State Key Laboratory of Technologies in Space Cryogenic Propellants,Beijing 100028,China;School of Energy and Power Engineering,Huazhong University of Science and Technology,Wuhan 430074,China)

机构地区：[1]航天低温推进剂技术国家重点实验室,北京100028 [2]华中科技大学能源与动力工程学院,湖北武汉430074

出　　处：《中南大学学报（自然科学版）》2021年第5期1666-1672,共7页Journal of Central South University:Science and Technology

基　　金：航天低温推进剂技术国家重点实验室基金资助项目(SKLTSCP1813)。

摘　　要：以液氢流动沸腾时气泡的脱离为研究对象,通过对其切向和法向的受力分析,建立气泡脱离模型,并对实验数据进行验证。在该模型的基础上,研究重力加速度、流速、壁面过热度、表面张力以及压力对气泡的升起直径及滑移直径的影响。研究结果表明:该模型具有较高的计算精度;在低流速下,氢气气泡的升起直径随重力加速度的减小而逐渐增大;高流速下剪切升力的影响更为显著,重力加速度的变化对气泡升起直径的影响可忽略;气泡的滑移直径随流速的增大而减小。此外,在微重力条件下,由于浮升力作用的减弱,壁面过热度、表面张力及压力的变化对气泡升起直径的影响更为显著。The bubble departure during liquid hydrogen flow boiling was studied,and a bubble departure model was established based on the analysis of the tangential and normal forces of a single hydrogen bubble.This model was verified with the experimental data.The effects of gravitational acceleration,velocity,wall superheat,surface tension and pressure on the bubble lift-off diameter and slide diameter were analyzed based on the model.The results show that the model has good calculation accuracy.And the lift-off diameter of hydrogen bubble increases with the decrease of gravitational acceleration at low flow velocity.On the contrary,the effect of shear stress is more significant at high flow velocity,and the effect of gravitational acceleration on the bubble lift-off diameter is negligible.In the horizontal direction,the bubble slide diameter decreases with the increase of flow velocity.Under microgravity condition,the effects of wall superheat,surface tension coefficient and pressure to bubble lift-off diameters are more significant due to the weakening of buoyancy.

关 键 词：微重力 低温 沸腾 气泡 气泡脱离直径 受力平衡分析 

分 类 号：TQ028.8[化学工程]