关于在两个平行板之间蒸发和凝结期间发生的矛盾现象
1Department of Mechanical Engineering, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA.
The Journal of chemical physics
|October 16, 2023
概括
与之前的假设相反,蒸汽蒸发和凝结中的温度逆转是可能的. 这项研究整合了液相传输,揭示了对界面温度跳跃和热传递动态的新见解.
科学领域:
- 热力学是一种热力学.
- 流体动力学 流体动力学
- 热传递是一种热传递.
背景情况:
- 动力学理论预测,在平行板之间蒸发和凝结过程中,蒸汽相温度反转.
- 之前的研究忽略了液相传输,限制了动力学理论在热传递模型中的实际应用.
- 由于忽视了液相现象,理论预测和实际传热模型之间存在断开.
研究的目的:
- 将界面质量和热流条件与蒸汽和液体相的连续描述相结合起来.
- 为了获得对平行板之间蒸发和凝结的完整理解.
- 通过分析来重新推导温度反转的标准,并解释界面温度跳跃.
主要方法:
- 将界面质量和热流条件与散装蒸汽和液体相的连续模型集成.
- 温度逆转标准的分析推导.
- 对界面冷却和加热过程的分析,以解释温度跳跃.
主要成果:
- 每个接口的温度跳跃与外部应用的温度差异保持一致.
- 接口冷却和加热过程解释了温度反转,可能导致蒸汽温度超出强加的墙壁温度范围.
- 当蒸发的潜热量很小时,蒸发和凝结可以发生在温度梯度上.
结论:
- 该研究提供了平行板之间蒸发和凝结的综合模型,包括液相传输.
- 温度逆转和界面温度跳跃通过界面能量动态来解释.
- 这些发现挑战了传统的传热假设,并为实际应用提供了新的视角.
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