用于数据中心自然供冷的小温差热管循环特性与匹配机制研究

Two-phase thermosyphon loop under small temperature difference has been widely applied for free cooling of Internet data centers, and to solve the problem of insufficient driving force, liquid-side and gas-side mechanically driven heat pipe have been developed recently. It is of great significance for rational and efficient application of heat pipe cycles, to reveal the difference, similarity, and matching mechanism under different driving mechanisms. In the project, a three-mode (gravity-driven, liquid-side mechanically driven, gas-side mechanically driven) test platform, a numerical simulation model and a theoretical analysis model, will be established. Based on the same platform: (1) to study the influence mechanism of the driving mechanism on the flow and heat transfer characteristics of the heat pipe cycle, and to clarify the flow and heat transfer characteristics of the heat pipe under three driving modes, and the main mechanism of enhancing the heat transfer performance by mechanical driving; (2) to study the matching relationships among heat transfer performance, mass flow rate and driving pressure head, and establish the regulatory mechanism considering both efficiency and reliability; (3) based on the generalized heat exchanger model, to study the internal relations of heat transfer performance, operating range, driving power and irreversible loss, determine the matching mechanism between cycle form and operating condition, and evaluate the applicability range of different driving modes. The above research will deepen the essential understanding of the heat pipe cycle, provide a solid theoretical basis for the optimal design and operation regulation of heat pipe cycle, which is expected to develop its energy-saving potential.

小温差自然循环热管在数据中心自然供冷中应用广泛，为解决其驱动力不足等问题发展出液相/气相动力驱动循环热管，探明不同驱动方式下热管循环的共性机理、个性特征及匹配机制，对热管循环合理高效的应用具有重要价值。本项目拟利用三模式（重力驱动、液相动力驱动、气相动力驱动）热管循环实验台、模拟仿真和理论分析方法，在共有平台上对比研究：（1）驱动方式对热管循环流动传热特性的作用机理，探明三种驱动方式下热管循环的共性机理和个性特征，揭示液/气相动力驱动强化传热的主要作用机制和强化效果；（2）研究热管循环换热量、循环流量、驱动压头匹配关系，构建热管循环高效可靠调控机制；（3）基于热力学广义换热器分析，研究传热性能、运行范围、驱动功耗的内在联系，确定循环形式与运行工况匹配机制，界定各自适用范围。以上研究将深化对热管循环的热力学本质认识，为热管循环优化设计和运行调控提供理论基础，有助于充分发挥热管循环的节能潜力。

小温差自然循环热管在数据中心自然供冷中应用广泛，为解决其驱动力不足等问题发展出液相/气相动力驱动循环热管，探明不同驱动方式下热管循环的共性机理、个性特征及匹配机制，对热管循环合理高效的应用具有重要价值。本项目的主要研究内容及进展包括：1）搭建了带可视功能的三模式(重力驱动、液相动力驱动、气相动力驱动)热管循环实验台和通用的热管循环分布式参数模型，提出了基于“理想循环趋近度”的热管循环评价方法和设计指标；通过对比研究，探明了驱动方式对热管循环流动传热特性的作用机理，探明了三种驱动方式下热管循环的共性机理和个性特征，揭示了液/气相驱动强化传热的主要作用机制、强化效果和性能边界；2）探明了自然循环热管“自适应”调节规律及调节边界，研究了热管循环换热量、循环流量、驱动压头匹配关系，提出了动力热管“单倍循环”的调控方法并进行了实验验证；3）根据热力学广义换热器分析，研究了自然循环热管、液/气相动力循环热管、热泵循环的运行范围、传热性能、驱动功耗、不可逆损失的内在联系，构建了一套简化统一描述方法，阐明了自然循环热管、液/气相动力驱动循环热管、热泵循环的热力学区别和联系，界定各自适用范围；4）拓展了热管循环的应用，研制了用于机载电子设备散热的带蓄热结构的热管与热泵复合型散热系统，提出了一种基于热管循环的双源复合热泵与光伏热管理一体化系统。以上研究深化了对热管循环的热力学本质认识，为热管循环的优化设计和运行调控提供了理论指导。研究期间发表论文6篇（均为第一标注），其中SCI检索5篇（均为JCR Q1，申请人均为第一作者或通讯作者），申请发明专利5项，授权4项，参加国内外学术交流4次，培养研究生3名，超额完成了预期研究目标。