Nucleate boiling is the most efficient heat transfer mechanism when small temperature differences between the heating surface and the working fluid are involved. Many applications involve heat transfer via nucleate boiling including electricity generation in nuclear power plants, where fuel rods are clad in zirconium alloy. The advantages of the latter include high chemical and corrosion resistance and low neutron absorptivity. In this study, we review various surface modification techniques used to enhance nucleate boiling heat transfer. Using laser texturing, we designed four types of surfaces; their pool boiling heat transfer performance was tested with twice-distilled water under saturated conditions and at atmospheric pressure from the natural convection regime to the critical heat flux onset. Unsteady temperature fields were recorded using high-speed infrared thermography and the boiling process was visualized in the visible spectrum using a high-speed camera. Critical heat flux values between 598 kW m-2 and 1590 kW m-2 were recorded on the textured surfaces, representing 19 % to 217 % improvement over the reference surface, respectively. Heat transfer coefficients in the range from 34 kW m-2 K-1 to 55 kW m-2 K-1 were also recorded on the textured surfaces, which represents 30 % to 113 % improvement over the reference surface. Repeated experiments on the same surface have shown that the results have minimal deviation from one experimental run to another, which partly confirms the stability of laser-textured surfaces. The latter is especially necessary for the implementation of such surfaces in real systems.
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