An improved comprehensive semi-analytical model is devised and postulated to unveil the underlying physics of thin-film evaporating dynamics in a microfluidic channel using Al₂O₃ water nanofluid as working liquid with/without porous coating layer of nanoparticles. The model uses the mass transport equation based on the kinetic theory and the Young–Laplace equation for pressure differential and incorporates the slip boundary condition on the wall of the channel. It reveals that the wall slip is a crucial parameter that increases the cumulative heat transfer with decreased thickness of the thin-film evaporating meniscus. Furthermore, mainly three volume fractions 0.5%, 1%, and 2% has been considered in the present work and it is observed that nanofluid plays an important role in the increment of heat flux which is about 31% with the volume fraction of 2% and 25 nm diameter particles when only enhanced thermophysical properties are considered without slip. However, it exaggerates the results by 29% when porous coating layer of nanoparticles is neglected. It is also noticed that a porous coating layer deposited by the nanoparticles can even reduce the heat transfer phenomenon. Moreover, for a given combination of nanoparticle diameter and volume fraction, increase in the thermal resistance may reach up to an extent that even increased thermal conductivity cannot counteract it and hence, the heat transfer obtained using nanofluid can be worse than the heat transfer obtained using the base liquid water alone.

设计并提出了一种改进的综合半分析模型，以揭示使用Al ₂ O ₃的微流体通道中薄膜蒸发动力学的基本物理原理。水纳米流体作为工作液体，具有/不具有纳米颗粒的多孔涂层。该模型将基于动力学理论的传质方程式和Young-Laplace方程用于压差，并将滑移边界条件纳入通道壁。它揭示了壁滑是一个关键参数，它随着薄膜蒸发弯液面厚度的减小而增加了累积传热。此外，在目前的工作中，主要考虑了三个体积分数0.5％，1％和2％，并且观察到纳米流体在热通量的增加中起着重要的作用，当体积分数为2％时，其约为31％。当仅考虑增强的热物理性能而没有打滑时，则使用直径25 nm的颗粒。然而，当忽略纳米颗粒的多孔涂层时，结果将结果放大了29％。还应注意，由纳米颗粒沉积的多孔涂层甚至可以减少传热现象。此外，对于纳米颗粒直径和体积分数的给定组合，热阻的增加可能会达到某种程度，即使增加的热导率也无法抵消它，因此，使用纳米流体获得的传热会比使用纳米流体获得的传热更糟。仅基础液态水。