ABSTRACT

One of the methods to improve the pool boiling process is electrodeposition, which is cheap, simple, and creates a strong bond in the structure. Besides, it can produce controllable porosity and improve boiling performance. In this paper, experiments were conducted in atmospheric conditions, using deionized water and hierarchical patterns created by a combination of 6-step electrodeposition and photolithography. The modified surfaces are characterized by X-ray diffraction (XRD), scanning electronic microscopy (SEM) images, and profilometric analysis. Besides, the effect of various parameters, including diameter, distance from perimeter to perimeter and wettability, along with the effect of nucleation site’s density (NSD), and effective surface area were investigated. Prediction of critical heat flux (CHF) values and experimental data showed that capillary effect of these surfaces increased the maximum heat flux compared to the plain surface. Also, changing the morphology of deposition and creating the volcano-shape structures were identified as a more suitable place for nucleation and enhancing the capillary effect and the effect of porosity and roughness. The maximum heat flux and heat transfer coefficient (HTC) for sample number 16 reached 145.36 $W/c{m}^2$ and 13.13$W/K.c{m}^2$ respectively, which was proportional to the improvement of 118.8% and 119% relative to the plain surface.

摘要

改善池沸腾过程的方法之一是电沉积，它便宜、简单，并在结构中形成牢固的结合。此外，它可以产生可控的孔隙率并改善沸腾性能。在本文中，实验是在大气条件下进行的，使用去离子水和通过 6 步电沉积和光刻相结合创建的分层图案。改性表面的特征在于 X 射线衍射 (XRD)、扫描电子显微镜 (SEM) 图像和轮廓分析。此外，还研究了各种参数的影响，包括直径、周长到周长的距离和润湿性，以及成核位点密度 (NSD) 和有效表面积的影响。临界热通量 (CHF) 值的预测和实验数据表明，与平面相比，这些表面的毛细管效应增加了最大热通量。此外，改变沉积形态和创造火山形结构被认为是更适合成核和增强毛细管效应以及孔隙率和粗糙度效应的地方。16号样品的最大热流量和传热系数（HTC）达到145.36$W/C{米}^{\mathrm{2个}}$和 13.13$W/钾.C{米}^{\mathrm{2个}}$分别与普通表面的 118.8% 和 119% 的改善成正比。