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通过实验研究了相变温度为50℃的相变微胶囊悬浮液在1 mm微小圆管内的换热特性,并与相同条件下的蒸馏水换热进行了对比。结果表明,在雷诺数(Re)为300~1000范围内,不同浓度的相变微胶囊悬浮液平均换热系数和平均努塞尔数(Nu)均高于蒸馏水,且随Re的增加而增大;相同Re下,相变微胶囊悬浮液的平均壁面温度低于蒸馏水,且随Re的增大而减小;随着相变微胶囊质量分数的增加,平均换热系数和平均Nu逐渐增大、平均壁面温度逐渐降低。
The heat transfer characteristics of the phase-change microcapsule suspension with a phase transition temperature of 50 ℃ in a 1 mm tube were experimentally studied and compared with the heat transfer of distilled water under the same conditions. The results show that the average heat transfer coefficient and the average Nusselt number (Nu) of phase change microcapsules with different concentrations are higher than that of distilled water at Reynolds number (Re) of 300 ~ 1000, and increase with the increase of Re Under the same Re, the average wall temperature of phase change microcapsule suspension is lower than that of distilled water, and decreases with the increase of Re. With the increase of mass fraction of phase change microcapsules, the average heat transfer coefficient and average Nu gradually increase Large, average wall temperature gradually decreased.