We investigated experimentally the heat transfer mechanisms in saturated pool boiling of water. In the experiment, the temperature of a sapphire heated wall with a titanium thin-film heater was visualized using a high-speed infrared camera with a spatial resolution of 82 μm/pixel and a framing rate of 3,000 fps. Local heat transfer characteristics of the fundamental heat transfer processes, including microlayer evaporation, dry-out, transient heat conduction immediately after rewetting, and convective heat transfer, were investigated based on the surface heat flux distribution obtained by three-dimensional transient heat conduction analysis of the heated wall. The contribution of microlayer evaporation, which shows a high heat flux far exceeding the applied heat flux, to the bubble growth was found to be about 50%, and the heat transfer within the microlayer was dominated by one-dimensional heat conduction in the thickness direction. It was confirmed that the local heat removal immediately after rewetting of the dry patch can be reproduced by the transient heat conduction model. The enhancement of convection by the isolated bubble motion was small, while the interaction between bubbles agitated the liquid strongly and enhanced the convective heat transfer. Via partitioning the heat flux distribution by image analysis, the convective heat transfer was found to be the dominant wall heat transfer mode, and the contribution of the microlayer with an area coverage ratio with respect to the total heat transfer area of less than 10% was small, around 25%.

我们实验研究了饱和池水沸腾过程中的传热机理。在实验中，使用具有空间分辨率为82μm/像素和成帧速率为3,000 fps的高速红外摄像头，可以看到带有钛薄膜加热器的蓝宝石加热壁的温度。根据通过三维热瞬态分析获得的表面热通量分布，研究了基本热传递过程的局部热传递特征，包括微层蒸发，变干，重新润湿后立即进行瞬态热传导和对流热传递。加热的墙。发现微层蒸发对气泡生长的贡献约为50％，该微层蒸发显示出远超过所施加的热通量的高热通量，微层内的传热主要是沿厚度方向的一维热传导。可以确认，通过瞬态热传导模型，可以将干贴剂重新润湿后立即去除局部热量。孤立的气泡运动增强了对流，而气泡之间的相互作用强烈搅动了液体并增强了对流传热。通过图像分析划分热通量分布，发现对流换热是主导的壁传热方式，面积比为10％以下的微层对总传热面积的贡献为小，大约25％。可以确认，通过瞬态热传导模型，可以将干贴剂重新润湿后立即去除局部热量。孤立的气泡运动增强了对流，而气泡之间的相互作用强烈搅动了液体并增强了对流传热。通过图像分析划分热通量分布，发现对流换热是主导的壁传热方式，面积比为10％以下的微层对总传热面积的贡献为小，大约25％。可以确认，通过瞬态热传导模型，可以将干贴剂重新润湿后立即去除局部热量。孤立的气泡运动增强了对流，而气泡之间的相互作用强烈搅动了液体并增强了对流传热。通过图像分析划分热通量分布，发现对流换热是主导的壁传热方式，面积比为10％以下的微层对总传热面积的贡献为小，大约25％。气泡之间的相互作用强烈搅动了液体并增强了对流传热。通过图像分析划分热通量分布，发现对流换热是主导的壁传热方式，面积比为10％以下的微层对总传热面积的贡献为小，大约25％。气泡之间的相互作用强烈搅动了液体并增强了对流传热。通过图像分析划分热通量分布，发现对流换热是主导的壁传热方式，面积比为10％以下的微层对总传热面积的贡献为小，大约25％。