超临界二氧化碳布雷顿循环系统是我国未来能源动力领域重点研发的战略性前沿技术之一，其中印刷电路板式换热器是保证系统高紧凑度和高效率的关键设备。针对目前印刷电路板式换热器换热预测模型可用范围窄、运行预测精度差等问题，本项目以Z字形通道印刷电路板式换热器为研究对象，以超临界二氧化碳和水为工质，针对这种复杂通道内超临界二氧化碳-水换热条件下超临界二氧化碳流动传热的多场协同机制、局部传热的参数调控规律等关键科学问题，通过基础性实验研究、多尺度数值分析和多场协同分析方法，明确超临界二氧化碳流动传热过程中流场、温度场和物性的协同机制，揭示局部传热机理，探究局部传热对整体传热的影响规律，建立超临界二氧化碳在印刷电路板式换热器内的流动传热机理模型，实现印刷电路板式换热器换热的可靠预测。本项目的研究对揭示超临界二氧化碳流动传热机理具有重要科学意义，同时为印刷电路板式换热器的工程应用和优化设计提供理论支持。

Supercritical carbon dioxide (sCO2) Brayton cycle is one of the advanced strategic technical equipment that our country will focus on R&D (Research and Development) in the future, in which the printed circuit heat exchangers (PCHEs), used as the recuperators and precooler, are the key facilities to ensure the high system compactness and high cycle efficiency. At present, there are many problems about the heat transfer prediction model in PCHE such as the relative narrow scope of application and poor operation prediction accuracy. In this project, using water as the coolant, the investigation will be performed to deal with the key scientific problems of sCO2 heat transfer including the multi-field synergy mechanism and the parameters control law of local heat transfer in PCHE with semi-circular zig-zag channel. The basic experimental research, multi-scale numerical analysis and multi-field synergy analysis will be combined to reveal the synergy mechanism between flow field, temperature field and properties of CO2, the local heat transfer mechanism and its effect on the overall heat transfer characteristics. Finally, a reliable model of sCO2 heat transfer can be proposed to predict the heat transfer in PCHE. The outcome of this project has significant scientific importance to reveal the flow and heat transfer mechanism of sCO2, and can provide the theoretical support for the engineering applications and the geometric optimal design of PCHEs.