多自由度动载下微通道流动沸腾临界热流密度触发机制研究

Microchannel flow boiling device is a key component to realize high efficiency cooling of marine equipment. The multi-DOF dynamic load introduced by the marine environment leads to the complexity of flow boiling process. An accurate understanding of the Critical Heat Flux (CHF) trigger mechanism is significant to safety operation of marine equipment..The trigger mechanism of CHF in microchannel flow boiling process refers to unsteady evolution of gas-liquid phase change accompanied by thermal-hydraulic parameter fluctuation subjected to multi-DOF dynamic load. However, the trigger mechanism of CHF is not clear due to the complexity of the physical process and the lack of deep study in accurate design under the high efficiency-led background. In this study, theoretical analysis, experimental research and numerical simulation method will be utilized to solve three scientific problems facing CHF subjected to multi-DOF dynamic load: (1) the dynamic response of thermal-hydraulic parameters; (2) the gas-liquid phase change evolution mechanism and the dynamic characteristics of flow patterns; (3) the quantitative analysis of CHF under multifactor coupling. With the above three problems solved, the trigger mechanism of CHF will be clarified..The research results of this study will enrich the theory of gas-liquid two phase flow with the effect of outer force, which will provide the theoretical basis for microchannel boiling device design optimization and safety operation under marine environment.

微通道流动沸腾装置是实现海洋装备冷却最为关键的一环。海洋环境下的多自由度动载导致沸腾过程更为复杂，准确把握其临界热流密度（Critical Heat Flux，CHF）触发机制对海洋装备的安全运行具有重要意义。.海洋环境下微通道流动沸腾CHF触发机制的研究涉及动载下伴随水力热力参数波动的气液相变非稳态演化。然而，由于物理问题复杂性以及换热效率主导体制下缺乏精准化设计的深入研究，多自由度动载下CHF触发机制尚未明确。本研究将结合理论分析、实验研究和数值模拟，解决海洋环境下微通道流动沸腾CHF触发机制面临的三个科学问题：（1）水力热力参数的动态响应；（2）气液相变演化规律和流型动力学特性；（3）多因素耦合下CHF的定量分析。在此基础上，全面揭示多自由度动载下微通道流动沸腾CHF触发机制。.研究成果将丰富外场作用下气液两相流理论，为海洋环境下微通道流动沸腾装置的优化设计和安全运行提供理论依据。

随着核电站、浮式液化天然气平台(FLNG)、船舶动力装置、海水淡化、船舶电源等领域的发展，关键部件的散热日趋重要。流动沸腾临界热流密度（CHF）涉及海洋工况下设备的安全运行。本项目以流动沸腾为基本问题，分析了微通道中的主导力及其对气液两相演变特性的影响；明确了海洋引入的动载，通过数值模拟和UDF函数编写对微通道流动沸腾宏观热力参数波动特性展开了研究；构建了CHF理论模型，提取了影响CHF的特征向量，基于力平衡和量纲分析建立了CHF无量纲参数预测模型，实现了CHF的准确预测；从宏观热力参数和微观气液两相演变全面阐明了CHF的触发机制。最终考察了微通道流动沸腾换热部件在典型能量系统中应用，初步掌握了强化微通道相变传热的方法，为微通道的设计与优化奠定了基础。.项目研究成果凝练为SCI学术论文7篇（均第一作者，4篇第一标注，3篇第二标注），参与国内外学术会议4次。在本项目的资助下，培养硕士研究生4人。