Abstract The main objective of the study was to present the Chilton-Colburn analogy in relation to mass and heat transfer processes occurring in minichannels. Because of the so-called scaling effects being in channels of small geometry the validation of the analogy between transfer processes in the case of convective fluid flow through the mninichannels seems to be necessary. The paper provides an overview of the experimental results of mass and heat transfer measurements performed under analogical conditions. The investigations concerned transfer processes in minichannels of different geometry. Channels with circular and rectangular cross section of small hydraulic diameter have been discussed. The ratio of minichannel length to the hydraulic diameter has been taken into account in the considerations. The analysis has been provided on the basis of the available literature results and the own author's investigations on mass transfer in short circular minichannels and preliminary results of mass transfer in long square channels of the mini heat exchanger. In order to validate the Chilton-Colburn analogy between mass and heat transfer the cases of transfer processes in minichannels which best meet the conditions of geometrical similarity have been discussed. The considered cases of heat transfer were experimentally studied with the use of thermal balance method while the mass transfer processes were investigated using the limiting current technique. On the basis of the analysis performed no definite answer was found on confirm Chilton-Colburn analogy applied in minichannels. Both convergence and divergence of results were noted. The discrepancy between thermal results and the results received from Chilton-Colburn analogy may be due to various reasons. One of them is a difference in the geometry of tested channels. Further research in conditions of full similarity of the channels geometry is expected. Another problem concerns thermophysical properties of the fluids used in investigations. The application of gases and liquids in thermal and mass experiments respectively, may cause a deviation from the mass/heat transfer analogy in minichannels. Measurement uncertainty also plays an important role in the discussion on the analogy between mass and heat transfer processes during the fluid flow through the channels of small characteristic dimensions. The total validation of mass/heat transfer analogy in minichannels in the form of Chilton-Colburn formula requires further experimental research.

中文翻译：

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在对流流体流过微通道的情况下的传热/传质类比

摘要 本研究的主要目的是展示与微通道中发生的传质和传热过程相关的 Chilton-Colburn 类比。由于小几何通道中的所谓缩放效应，在对流流体流过微通道的情况下，验证传输过程之间的类比似乎是必要的。本文概述了在类比条件下进行的传质和传热测量的实验结果。研究涉及不同几何形状的微型通道中的传输过程。已经讨论了具有小水力直径的圆形和矩形横截面的通道。在考虑中已经考虑了微通道长度与水力直径的比率。该分析是在现有文献结果和作者对短圆形微通道中传质的研究以及微型换热器长方通道中传质的初步结果的基础上提供的。为了验证传质和传热之间的 Chilton-Colburn 类比，讨论了最符合几何相似性条件的微型通道中的传递过程的情况。使用热平衡方法对所考虑的传热情况进行了实验研究，而使用极限电流技术研究了传质过程。根据所进行的分析，在确认 Chilton-Colburn 类比在微通道中应用时没有找到明确的答案。注意到结果的趋同和分歧。热结果与从 Chilton-Colburn 类比得到的结果之间的差异可能是由于多种原因造成的。其中之一是测试通道几何形状的差异。预计在通道几何形状完全相似的条件下进行进一步研究。另一个问题涉及研究中使用的流体的热物理特性。气体和液体分别在热和质量实验中的应用可能会导致与微型通道中的质量/热传递类比的偏差。测量不确定度在流体流过小特征尺寸通道期间传质和传热过程之间的类比的讨论中也起着重要作用。