摘要: |
相变微胶囊悬浮液(MEPCMS)作为一种新型功能性热流体,在热管理、储能等诸多领域极具发展潜力。本文采用离散相模型(DPM)研究非均匀热流下细小水平矩形通道内MEPCMS的传热特性。结果表明:悬浮液中颗粒相变能够强化传热,在热流密度分布为9-5-5 W/cm2、进口流速为0.40 m/s、质量分数为10%时,悬浮液最高能够使壁面和流体温升分别降低8.79%和15.14%。热泳作用使得颗粒在流动过程中会往低温区域迁移。与均匀热流条件相比,局部热流的分布会影响该区域及后边区域的传热特性。随着进口流速和质量分数提高,流体对壁面的冷却效果得到提高,同时进出口压降也有所增加。 |
关键词: 相变微胶囊悬浮液 离散相模型 非均匀热流 强化传热 |
DOI: |
投稿时间:2022-10-23 修订日期:2023-03-27
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基金项目::国家自然科学基金( U20A20299) ,广东省自然科学基金( 2019A1515012119) 资助项目。 |
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Heat Transfer Characteristics of Microencapsulated Phase Change Material Slurry in a Minichannel with Nonuniform Heat Flux |
Li Zilong, Wang Zhibin, Jia Lisi, Chen Ying, Mo Songping
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(Guangdong Provincial Key Laboratory of Functional Soft Matter, School of Material and Energy, Guangdong University of Technology) |
Abstract: |
As a new functional thermal fluid, microencapsulated phase change material slurry (MEPCMS) has development potential in thermal management and other fields. In this study, the discrete phase model (DPM) was used to investigate the heat transfer characteristics of MEPCMS in a horizontal rectangular minichannel under nonuniform heat flux conditions. The results show that the heat transfer can be enhanced by the phase change of particles in the slurry, and the slurry can reduce the wall temperature rise by 8.79% and the fluid temperature rise by 15.14% at a heat flux distribution of 9–5–5 W/cm2, inlet velocity of 0.40 m/s, and mass fraction of 10%. Thermophoretic force causes the particles to migrate to the low-temperature region during the flow. Compared with the uniform heat flux condition, the region and magnitude of the local heat flux affect the heat transfer characteristics in this and later regions. As the inlet velocity and particle mass fraction increase, the cooling effect of the fluid on the wall improves. However, the pressure drop also increases owing to the influence of the streamwise resistance and two-phase interaction. |
Key words: microencapsulated phase change material slurry discrete phase model non-uniform heat flux heat transfer enhance |