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[Display omitted] • Effect of surface structure with T-shaped micro-fins channel on pool boiling was investigated. • T-shaped micro-fins structure promoted bubble departure. • Fresh liquid replenished capacity enhanced by gap between fins. • The best boiling heat transfer enhancement obtained from S1 surface, which the ratio is 184.7% compared with smooth surface. • The simplified model was developed to predict heat flux with a ± 40% error. The saturated pool boiling heat transfer performance on the surface of T-shaped micro-fins was investigated with deionized water as working medium. Ten different T-shaped micro-fins surfaces were fabricated by machining method and the pool boiling experiments were carried out. By comparing the influence of varios parameters on the boiling heat transfer performance, the results showed that reducing the width of upper fin, increasing the gap or height of upper fin can improve the boiling heat transfer coefficient. With the increase of the width of the lower fins, the boiling heat transfer performance showed a different trend, that is, it increased at first and then decreased. The maximum boiling heat transfer coefficient of the surface S1 to the smooth surface was 184.7%. The visualization results showed that the merging of bubbles on the outside of the channel surface could strengthen the vertical and horizontal replenishment of the liquid to dry spot in the channel, thereby delaying the occurrence of critical heat flux and effectively reducing the wall temperature. The simplified semi-analytical model to determine the total heat flux of the micro channeal was proposed, which provided a heat flux prediction with an error of ± 40%. [ABSTRACT FROM AUTHOR]

· Surface modification methods (macro and micro) and heat transfer mechanisms commonly used in boiling are reviewed. · The typical boiling experiment devices are listed. · The empirical correlation formulas for predicting the detach diameter and detach frequency of bubbles are summarized. · The fractal method applicable to pool boiling are summarized. · The empirical correlation formulas for predicting the detach diameter and detach frequency of bubbles are evaluated. As an effective way to strengthen pool boiling, surface modification has been widely studied by many scholars. In this paper, the enhancement of pool boiling heat transfer by regular surface structure modification was reviewed, including macro and micro scales. The systematic summary results showed that the pool boiling heat transfer performance of the structured surface with two scales are improved in different degrees compared with that of the ordinary smooth surface. The existence of macro-structure can eliminate the boiling lag caused by refrigerant to a certain extent, while the micro-structure (microcolumns, microgrooves and micropores) can improve the vaporization core density, bubble departure diameter and critical heat flux to varying degrees. Under the condition of low heat flux, the trend of bubble departure diameter on different structural surfaces is different, so as the bubble departure frequency. Further research is needed to determine the dynamic parameters of bubbles on structural surfaces. In addition, the semi-empirical formula of heat flux and boiling heat transfer curve in literature were summarized. [Display omitted] [ABSTRACT FROM AUTHOR]