ABSTRACT

In this research work, pool-boiling heat transfer is conducted with the consideration of $\mathrm{T}\mathrm{i}{\mathrm{O}}_2$ hydrophilic nanoparticles as coating material using Electrospray Deposition (ESD) method. The study focused on the impact of spray parameters such as injection flow rate, solution concentration, and spray time on the formation of the coating structure, porosity, cavity characteristics, and thickness. Moreover, X-ray diffraction (XRD), Energy Dispersive X-ray spectroscopy (EDX), Profilometric Analysis, and Scanning Electronic Microscopy (SEM) images were utilized to analyze the surfaces. As a result, pool boiling was ameliorated by reaching the effective cavity size, rewetting the surface, and improving the bubble departure mechanism. Furthermore, the coating’s stability and adhesion were examined in the boiling results, due to the existence of a small decrease in the curves. The optimal case increased the Maximum Heat Flux (MHF) and maximum Heat Transfer Coefficient (HTC) up to 90% and 118.3%, respectively. In addition, reduced the superheat temperature to 31.7% relative to the plain copper surface.

摘要

在这项研究工作中，池沸腾传热是在考虑$\mathrm{吨}\mathrm{一世}{\mathrm{○}}_2$使用电喷雾沉积 (ESD) 方法作为涂层材料的亲水性纳米颗粒。该研究的重点是喷射流量、溶液浓度和喷射时间等喷射参数对涂层结构形成、孔隙率、空腔特性和厚度的影响。此外，利用 X 射线衍射 (XRD)、能量色散 X 射线光谱 (EDX)、轮廓分析和扫描电子显微镜 (SEM) 图像来分析表面。结果，通过达到有效空腔尺寸、重新润湿表面和改进气泡离开机制来改善池沸腾。此外，由于曲线存在小幅下降，因此在沸腾结果中检查了涂层的稳定性和附着力。最佳情况将最大热通量 (MHF) 和最大传热系数 (HTC) 分别提高了 90% 和 118.3%。此外，相对于普通铜表面，过热温度降低至 31.7%。