燃料电池内部冷却液强化沸腾传热机理研究

PEMFC effect thermal management has become a key technical challenges to further improve efficiency and break necessarily performance of the fuel cell. The internal cooling of the fuel cell is an important part of thermal management. The coolant flow, coolant flow condition and distribution of the temperature field impact directly on the cooling effect of the entire fuel cell. .Taking the fuel cell process theory as the background, the mechanism of the coolant flow state to affect on heat transfer process of the battery pack is revealed.Highly efficient thermal management design theories and model are provided.Battery gas solid-liquid-coupled in heat transfer calculation model is established to study the course of temperature distribution.Meanwhile, an advanced experimental method is carried out to test the local temperature and local heat flux distribution in micro-channel direction, which determines the local heat transfer coefficients.The law of flow and heat transfer are analyzed and a science path is put forward to strengthen heat transfer..By the simulating phase change heat transfer process, the efficiency of heat transfer will be provided and the changes of flow patterns of the ideal cooling in the coolant circulation system are reduced.This research project can provide an theoretical guidance to optimize coolant flow patterns within the battery pack and develop the control strategy for efficient thermal management system.

对PEMFC进行有效热管理，已成为进一步提高效率、改善燃料电池的性能所必须突破的关键技术难题。燃料电池内部冷却散热是热管理重要组成部分，冷却液流动条件、温度场分布都直接影响整个燃料电池的冷却效果。本课题依据燃料电池工作过程理论，揭示电池组内冷却液流动状态对电池组传热过程的作用机理，提出实现高效热管理设计理论及模式。建立电池内气固液耦合传热计算模型，研究高热通量工况下的温度场分布的变化过程。通过实验测试电池内微通道方向上温度和热流分布用以确定对流换热系数，并在实测基础上分析其对流换热规律，同时寻求进一步强化传热的技术途径。通过对沸腾传热过程的模拟，提出有利于提高传热效率、减少冷却液循环系统变动的理想冷却流动模式。本研究项目可为优化电池组内冷却液流动模式，制定高效热管理系统控制策略，提供理论指导。

质子交换膜燃料电池（PEMFC）整体温度控制与内部温度分布均匀性对维持电化学反应的正常进行和质子交换膜的长期稳定工作有着重要的影响，亦是燃料电池研究的关键技术难题。本课题首先通过PEMFC工作过程理论分析和数值计算表明：传统PEMFC内部冷却液循环冷却系统难以避免电池内部局部温度过高的难题，因而首次提出微通道阵列相变传热技术，丰富了燃料电池热管理理论。其次，开发新型高效热管理系统装置，其核心散热部件为微通道阵列相变传热元件。通过数值模拟计算表明：新型热管理系统有效解决了燃料电池内部温度分布不均匀性的瓶颈问题。进一步研究发现，微通道几何参数变化对电池内部散热效果有很大影响。因而，探究电池内部微通道内相变传热机理以及沸腾强化传热机理有着重要的科学意义。