石墨烯复合相变微胶囊悬浮液的对流换热特性

doi:10.16085/j.issn.1000-6613.2017-1525

摘要/Abstract

摘要： 相变微胶囊悬浮液是将相变微胶囊分散到基液中形成的功能热流体，能实现储热及热输运一体化，大大提高了基液的储、载热密度，但由于相变微胶囊的热导率较低，影响了悬浮液的传热性能。为了提高相变微胶囊的导热性能，本文制备了掺杂石墨烯的复合相变微胶囊，并将其分散在水中形成相变微胶囊悬浮液。搭建了实验台，对比研究了水、相变微胶囊悬浮液、石墨烯复合相变微胶囊悬浮液的管内对流换热特性。结果表明，相变微胶囊悬浮液对流换热系数随着浓度的增加而降低，随着温度的升高而增加，并且当流速大于1.5m/s时，质量分数15%的石墨烯复合相变微胶囊悬浮液的对流换热系数大于水，表现出良好的传热特性。研究结果可为相变微胶囊悬浮液热输运系统的设计提供参考与依据。

关键词: 相变微胶囊悬浮液, 相变, 悬浮系, 对流, 传热

Abstract: Microcapsule slurries, produced by adding microcapsule particles into the base fluid, exhibit high heat storage and carrier density. They can be used in both heat storage and heat transport. However, one of the main disadvantages of microcapsule slurries is their low thermal conductivity due to the low thermal conductivity of microcapsules. To improve the thermal conductivity of the phase change microcapsules, a composite phase change microcapsule doped with graphene was prepared. The microcapsule slurries were then prepared by dispersing the microcapsules in water. An experimental system was set up to investigate convective heat transfer characteristics of water, phase change microcapsule slurries and the graphene-based phase change microcapsule slurries by allowing them flow in a horizontal tube. The experimental results show that that the convection heat transfer coefficient increases with the rise of temperature and decreases with the increase of concentration. Furthermore, when the velocity is greater than 1.5m/s, the heat transfer coefficient of 15% graphene-based microcapsule slurries are higher than that of water, which shows good heat transfer performance. The results provide a reference and basis for the design of heat transport system using microcapsule slurries.

Key words: phase change microcapsule slurry, phase change, suspensions, convection, heat transfer

中图分类号:

TB65

申俊锋, 邹得球, 刘小诗, 郭江荣, 胡云平, 胡志钢, 刘默. 石墨烯复合相变微胶囊悬浮液的对流换热特性[J]. 化工进展, 2018, 37(06): 2323-2330.

SHEN Junfeng, ZOU Deqiu, LIU Xiaoshi, GUO Jiangrong, HU Yunping, HU Zhigang, LIU Mo. Convection heat transfer characteristics of graphene-based phase change microcapsule slurries[J]. Chemical Industry and Engineering Progress, 2018, 37(06): 2323-2330.

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