【摘要】 随着电子电气设备向小型化与集成化发展，对热控制提出了更高要求。在传统传热流体中加入纳米颗粒、相变微胶囊（MEPCM）颗粒是一种解决设备散热冷却问题的可行方法。本文选用二氧化硅（SiO₂）纳米颗粒和三聚氰胺甲醛树脂/十八烷胶囊颗粒，分别以单一、混合的方式制备水基SiO₂纳米流体、MEPCM悬浮液和SiO₂/MEPCM悬浮液，在水平圆管内对这3种功能传热流体进行了对流换热实验。研究了雷诺数Re、混合质量比(■∶m_MEPCM)对流体传热和流动性能的影响。结果表明:在3种传热流体中，SiO₂/MEPCM悬浮液通过减小其混合质量比，在强化传热综合性能上获得的评价最高，可实现高效节能换热，且传热综合性能随Re的减小而增强;与传统水工质相比，SiO₂/MEPCM悬浮液在Re为3 153、■∶m_MEPCM为1∶3工况下的综合性能提升约78.77%。更多还原

【Abstract】 The miniaturization and integration of electronic and electrical equipments have imposed higher thermal management requirements. Incorporating nanoparticles and microencapsulated phase change materials（ MEPCM） into traditional heat transfer fluids is a feasible method to address the heat dissipation and cooling issues of such equipments. The silicon dioxide（SiO₂） nanoparticles and melamine-formaldehyde resin/octadecane microcapsules were used as additives for pure water to prepare SiO₂ nanofluid,MEPCM suspension,and SiO₂/MEPCM suspension in a single or mixed manner,respectively. Experiments were conducted on the convective heat transfer performance of these three heat transfer fluids in a horizontal circular tube,focusing on the effects of Reynolds number（ Re） and mixing mass ratio(■∶m_MEPCM) on the heat transfer and flow properties of the fluids. The results show that among the three kinds of heat transfer fluids,the SiO₂/MEPCM suspension can achieve the highest evaluation in comprehensive heat transfer enhancement by decreasing its mixing mass ratio,capable of achieving efficient and energysaving heat exchange,with this advantage becoming more pronounced as the Re decreases. Compared to the traditional pure water,the SiO₂/MEPCM suspension at Re of 3 153 and ■∶ m_MEPCMof 1∶ 3 can achieve an approximately 78. 77% improvement in comprehensive performance.更多还原