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给出了在低热流密度、负压条件下有限小空间内沸腾-凝结共存相变传热特性的实验研究结果。沸腾工质为去离子水,换热表面材料为紫铜,有限空间由加热铜柱的上表面和冷凝铜柱的下表面以及不锈钢圈的侧壁面构成,有限空间的高度为26 mm,充液液面高度从10 mm到16 mm。实验观察和测试结果表明,沸腾和凝结之间存在明显的相互作用和影响,随着液面高度的增加,沸腾表面传热系数先增加后减小。对压力信号的标准偏差分析表明,随着热流密度的增加,压力波动的标准差均呈现先增大后趋于常数的趋势,表明气泡受到了有限空间的影响.实验结果还表明,存在一个使沸腾和凝结表面传热系数最大的充液高度,这为优化平板热管均热器等存在沸腾-凝结共存现象的装置的设计提供了参考。
The experimental results of the heat transfer of boiling-condensing coexisting phase transformation in a limited space with low heat flux density and negative pressure are given. The boiling working fluid is deionized water, the surface material of the heat exchange is copper, and the limited space is formed by the upper surface of the heating copper column and the lower surface of the condensed copper column and the side wall surface of the stainless steel ring. The height of the limited space is 26 mm, Surface height from 10 mm to 16 mm. Experimental observation and test results show that there is obvious interaction and influence between boiling and coagulation. With the increase of liquid level, the heat transfer coefficient of boiling surface first increases and then decreases. The standard deviation of the pressure signal shows that with the increase of heat flux, the standard deviation of pressure fluctuation first increases and then tends to be constant, indicating that the bubble is affected by the limited space.The experimental results also show that there exists a Boiling and condensation surface maximum heat transfer coefficient of the liquid filling height, which is optimized for the flat heat pipe heatsink boiling co-existence of the existence of the device design provides a reference.