分形树状微小结构中流动沸腾传热机理及气液两相流动力学行为

项目名称： 分形树状微小结构中流动沸腾传热机理及气液两相流动力学行为

项目编号： No.51306033

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： 张程宾

作者单位： 东南大学

项目金额： 26万元

中文摘要： 微尺度流动沸腾是解决高热流密度微电子芯片散热问题的一个重要途径。本项目将分形树状结构引入至微尺度流动沸腾传热，以实现沸腾相变散热器工质输运和热量传递的优化配置，进一步强化散热性能。建立考虑分叉效应，表面张力，相界面热质传递、运动及变化的分形树状网络中流动沸腾的理论模型并进行数值模拟；采用MEMS工艺研制集成有微传感器的分形结构微通道芯片，测试流动沸腾传热与阻力特性，基于高速显微成像系统开展流型动态演化的可视化实验研究；探析沸腾相变、热量传递、两相流动、界面迁移以及多级微通道间流变相互作用的热力学和动力学耦合输运机制，并重点阐明树状分叉效应导致的气泡破裂分散与聚并融合过程的动力学行为，深入研究分形树状微小结构中的流动沸腾传热和流型演化的多尺度效应、树状分叉效应。本项目的研究不仅对于完善微尺度传热传质基础理论具有重要的科学意义，也将为MEMS换热器件的优化设计提供强有力的理论支撑。

中文关键词： 分形；微小结构；流动沸腾；树；传热传质

英文摘要： Recognizing the significant potential of microscale flow boiling heat transfer in high flux microelectronic cooling, the fractal tree-shaped geometry is introduced into it so as to obtain an optimal configuration of mass transfer and heat transport and hence to realize a more enhanced thermal removal performance. The project will develop a theoretical model of flow boiling in fractal tree-shaped networks with a consideration of bifurcation effect, surface tension, heat and mass transport occurring at interfaces as well as interfacial motion and transformation. The project will fabricate fractal tree-shaped silicon microchips integrated with micro sensors for flow boiling heat transfer by MEMS micromachining, measure the flow resistance and heat transfer performance of flow boiling in fractal structures, and conduct visualization experimental investigation on the dynamic evolution of the flow regime via high speed microscope camera. The coupled thermodynamics and kinetics mechanisms of boiling phase change, heat transfer, gas-liquid two-phase flow, interfacial motion and rheologic interaction among multi-level microchannels, especially the dynamic behaviors of breakup and coalescence process induced by the tree-shaped bifurcation effect, is explored and analyzed with a focus on the multiscale effect and tree-shap

英文关键词： fractal；micro structure；flow boiling；tree；heat and mass transfer