Analyses on Ground-based Results of Evaporation-convection Box Experiment Prepared for SJ-10 Satellite
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摘要: 实践十号卫星蒸发对流实验旨在研究置于加热底板的蒸发液滴在相变过程中,表面蒸发与表面张力驱动对流的耦合机理及其不稳定性.为与空间实验结果进行对比,利用蒸发对流箱完成在轨工况的科学匹配实验,获得相应工况的地面科学数据、工程参数及实验图像.通过对地面科学匹配实验结果进行分析,得到不同工况下液滴形貌(体积、表面积、接触角、液滴高度、液滴直径)变化规律,以及液滴蒸发过程中温度、热流量、蒸发速率和蒸发流量的变化规律.依据实验结果分析研究了具有质量交换的复杂流体相变界面的热质传输规律.Abstract: SJ-10 evaporation-convection experiment is designed to investigate the coupling mechanism and instability of the droplet evaporation and the convection driven by surface tension, during the process of evaporation phase changing when the droplet is deposited on a heated substrate. The heat transfer of evaporation and the evaporation surface non-equilibrium effect are mutually affected by heat conduction, buoyancy convection and the convection driven by surface tension. On the ground, heat conduction and buoyancy convection both play a leading role, but in the space, buoyancy convection will disappear and the thermal capillary convection rules. To make a contrast with space experiment, the scientific matching test under on-orbit working condition was completed with evaporation-convection box and the scientific data, engineering parameters and experiment images were obtained. At the same time, the ground research results were analyzed, and knowledge of the changing pattern of droplet morphology as well as those of temperature, heat flux, evaporation rate and evaporation flux, was acquired. Finally, according to the results of the experiment, the heat and mass transfer regularity of fluid phase-changing interface on which the mass exchange is happening, is analyzed.
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Key words:
- Droplet evaporation /
- Capillary convection /
- Buoyancy convection /
- Evaporation rate /
- Heat flux
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