潜热型功能热流体在微结构中流动换热机理研究

项目名称： 潜热型功能热流体在微结构中流动换热机理研究

项目编号： No.51306156

项目类型： 青年科学基金项目

立项/批准年度： 2014

项目学科： 能源与动力工程

项目作者： 刘东

作者单位： 西南科技大学

项目金额： 25万元

中文摘要： 由于体积限制而导致的巨大泵功消耗使得微结构冷却方式很难被推广。如果在微结构冷却中采用高表观比热容的潜热型功能热流体代替常规流体，那么在相同的散热量下工质流量就会减少，泵功就可能会降低。本项目拟通过实验和数值模拟的方法，研究潜热型功能热流体在微结构中流动和换热机理：（1）采用可视化观测方法，观测并分析相变微胶囊颗粒在微结构中的流动特性及其与微结构相互作用的现象；（2）运用红外热线仪和热电偶等工具观测温度场变化，研究不同相变材料浓度、流体的Re数，微胶囊颗粒大小对潜热型功能热流体的流动和换热特性的影响并分析总结换热特性；（3）在实验研究的基础上，运用数值分析的方法研究由剪切速率梯度和粘性梯度等因素导致的"微对流"效应、微胶囊内相变过程、微胶囊壁面热阻和微结构尺度效应等对潜热型功能热流体在微结构中流动换热的影响机理。通过上述研究，为将来潜热型功能热流体在微结构中的工程应用提供研究基础和理论支持。

中文关键词： 潜热型功能热流体；相变微胶囊；微结构；冷却换热；等效比热容模型

英文摘要： Micro-structured cooling is difficult to be widely used due to the costly pumping power as a result of volume constrains. Whereas the replacement of latent functional thermal fluid with the conventional fluids is able to improve the heat exchange performance of unit mass of working fluid, and thus reduce the pump power. This project intends to study the latent functional thermal fluid flow and heat transfer characters in the micro-structure via both experiments and numerical methods: (1) The flow characteristics of microcapsulated phase change particles in the micro-structure and its interaction with the micro-structure are viewed and analyzed using the visual observation method; (2) Using the infrared thermal imager and thermocouple, study the heat transfer characteristics of microcapsulated phase change particles in the micro-structure and the effect of the concentration of the different phase change materials, Re number and the particle size of the microcapsules and summary the heat transfer performance. (3) Based on the experimental studies, the numerical analysis is implemented to study the impact of "Micro-convection effect" which is caused by the shear rate and viscous gradient factors , the phase transition within the microcapsules, the microcapsule wall thermal resistance and the micro-structure scale a

英文关键词： latent-heat functional fluid；phase-change microcapsule particles；micro structures；cooling heat transfer；the equivalent heat capacity model