可变形表面池沸腾换热特性研究

Pool Boiling Heat Transfer Performance for Deformable Surfaces

微纳米结构表面是目前池沸腾强化换热的研究热点。但常规材料制备的换热表面在加工成型后无法改变几何结构,不能很好地适应发热器件的热负荷变化,而由形状记忆合金制成的可变形表面能够随着热流密度的变化改变几何形状,实现发热体表面温度的自适应热控制。基于上述思想,本文制备了四种疏水表面结构,研究对比了绝对压力为28 kPa下水在可变形表面与固定式表面之间的沸腾换热特性,并将实验结果与目前常用的实验关联式进行了对比,发现现有的关联式不能很好地预测可变形表面的实验结果,需要发展新的沸腾换热机理和理论公式。

The micro-nano structured surface was a research hotspot in the field of pool boiling heat transfer enhancement. It is known that after processing, the geometry manufactured by traditional materials cannot change to adapt to the heat load of heating devices. However, the deformable surface fabricated by shape memory alloys can change its geometry with heat flux to achieve the adaptive temperature control of heating surface. Based on the above-mentioned idea, four kinds of hydrophobic surfaces were fabricated to compare the boiling heat transfer performance in water at absolute pressure 28 kPa between the deformable and fixed surfaces. By comparing experimental results and classic theoretical correlation, it is found that the existing correlation cannot predict the experimental results of deformable surface well. So it is necessary to develop a new boiling heat transfer mechanism and theoretical formula.