Mohammadpour Loghman, Moghadasi Hesam, Moosavi Ali
School of Mechanical Engineering, Iran University of Science and Technology (IUST), Tehran, 16846-13114, Iran.
Department of Mechanical Engineering, Faculty of Engineering, Arak University, Arak, 38156-88349, Iran.
Sci Rep. 2025 Jan 2;15(1):527. doi: 10.1038/s41598-024-84127-3.
Dropwise condensation (DWC) is a widely studied vapor-liquid phase-change process that has attracted significant research attention due to its exceptional energy transfer efficiency. Therefore, it is highly important to predict the heat transfer rate during DWC and the factors that affect it. This study presents a computational fluid dynamics (CFD) investigation on DWC heat transfer under diverse circumstances for a single droplet on inclined and rough surfaces with Wenzel structure. Drop's shape simulation was done utilizing the Surface Evolver (SE) software and the governing equations were solved based on the finite volume method. Moreover, for different Nusselt numbers ([Formula: see text]), the average heat flux was calculated by considering the effect of different inclination angles, contact angles, and saturation temperatures. Validation was performed by comparing the outcomes with the available data in the literature, and a satisfactory agreement was achieved. The study revealed that the average heat flux for a water droplet with the saturation temperature [Formula: see text] = 313 K on an inclined surface with an inclination angle of β = 90° increases by 151.79% when the Nu is increased from 510 to 740. Similarly, for a droplet on a rough surface with a roughness index of [Formula: see text] = 0.6, the increase in heat flux is 152%. Moreover, an increase in saturation temperature results in a higher heat flux for both inclined and rough surfaces. The augmentation follows a specific trend for each of the surfaces.
滴状冷凝（DWC）是一种被广泛研究的气-液相变过程，因其卓越的能量传递效率而备受研究关注。因此，预测滴状冷凝过程中的传热速率及其影响因素至关重要。本研究针对具有文泽尔结构的倾斜粗糙表面上的单个液滴，在不同工况下进行了滴状冷凝传热的计算流体动力学（CFD）研究。利用表面演化器（SE）软件进行液滴形状模拟，并基于有限体积法求解控制方程。此外，针对不同的努塞尔数（[公式：见原文]），通过考虑不同倾斜角度、接触角和饱和温度的影响来计算平均热流密度。通过将结果与文献中的现有数据进行比较来进行验证，并取得了令人满意的一致性。研究表明，对于饱和温度[公式：见原文]=313 K的水滴，在倾斜角β = 90°的倾斜表面上，当努塞尔数从510增加到740时，平均热流密度增加151.79%。同样，对于粗糙度指数[公式：见原文]=0.6的粗糙表面上的液滴，热流密度的增加为152%。此外，饱和温度的升高会导致倾斜表面和粗糙表面的热流密度都更高。每种表面的增强都遵循特定趋势。
