Abstract In this work, the convective heat transfer of Al2O3-water nanofluid in a three-dimensional minichannel heat sink is exaimed numerically. The finite volume method (FOV) is applied to discrete the governing equations, and the LINE SOR and TDMA algorithms are used for solving the equations. The FORTRAN program has been developed for the numerical calculation. Ceiling of the minichannel is covered with the micro-encapsulated phase change material. The N-eicosane with the melting temperature of 34.7 °C and the latent heat of 24,300 J/kg is considered as the phase change material. The purpose of placing this material on the ceiling of the minichannel is to cool the working fluid by absorbing the heat from the fluid during melting. All simulations are performed for three values of solid volume fractions of nanoparticles including 0%, 2%, and 10%, two outer surface temperatures of ceiling including 28 °C and 30 °C, and the Reynolds number in the range of 500–2000. The effects of different parameters including the usage of the phase change material, the solid volume fractions of nanoparticles, the outer surface temperature of ceiling, and the Reynolds number on the thermal field, heat flux, melting rate of micro-encapsulated phase change material, and thermal resistance in the mini-channel heat sink are studied. The results reveal that the thermal resistance decreases about 10.88% by using the nanoparticles with solid volume fraction of 10% at Rebf = 500 and Tcw,0 = 28 °C for the case of bare celling. The heat flux received by the ceiling in heating section decreases by using the micro-encapsulated phase change material(MEPCM). In addition, the MEPCM melts faster at lower values of the Reynolds number.

中文翻译：

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微封装PCM冷却天花板微通道散热器中纳米流体对流传热的数值研究

摘要 在这项工作中，数值研究了三维微通道散热器中Al2O3-水纳米流体的对流传热。将有限体积法（FOV）应用于离散控制方程，并使用LINE SOR和TDMA算法求解方程。FORTRAN 程序是为数值计算而开发的。微通道的天花板覆盖有微封装相变材料。熔化温度为 34.7°C，潜热为 24,300 J/kg 的正二十烷被认为是相变材料。将这种材料放置在微通道顶部的目的是通过在熔化过程中从流体中吸收热量来冷却工作流体。所有模拟均针对三个纳米颗粒的固体体积分数值进行，包括 0%、2% 和 10%，天花板的两个外表面温度包括28°C和30°C，雷诺数在500-2000范围内。不同参数包括相变材料的使用、纳米粒子的固体体积分数、天花板外表面温度和雷诺数对微囊相变材料的热场、热通量、熔化速率的影响，并研究了微通道散热器中的热阻。结果表明，对于裸电池，在 Rebf = 500 和 Tcw,0 = 28 °C 下，使用固体体积分数为 10% 的纳米颗粒，热阻降低了约 10.88%。通过使用微囊相变材料（MEPCM），加热段天花板接收的热通量降低。此外，