变工况下超临界CO2离心压缩机局部凝结与主流掺混的流动机制

Supercritical carbon dioxide (S-CO2) brayton cycle has been proved the significant application potential in solar thermal power generation, nuclear power generation and waste heat utilization fields. However, the S-CO2 centrifugal compressor has to face partial condensation challenge. The unsteady flow mechanism of partial two-phase flow in high adverse pressure gradient environment still needs further investigation. This project will focus on the following research work: 1) Experimental exploration of the partial two-phase flow characteristics in S-CO2 centrifugal compressors. 2) Numerical analysis and design method development of S-CO2 centrifugal compressors. 3) Development of internal loss models regarding two-phase flow. Based on the results of experimental measurement and numerical analysis, new design method and strategy will be formed and the unsteady phenomenon of internal flow will be interpreted. This project is to clarify the two-phase flow characteristics of the S-CO2 centrifugal compressor in brayton cycle and provide theoretical support for creating design technology having intellectual property rights.

超临界二氧化碳布雷顿循环在太阳能热发电、核能发电及相关余热利用领域有着巨大的应用空间，已被业界专家认为是改变游戏规则的一项技术。但关键部件涡轮机中的离心压缩机内部流动将面临局部凝结的挑战，两相流动的特征在这种高逆压梯度环境下的非定常流动规律还需进一步加深认识，本申请项目将围绕：1）超临界二氧化碳离心压缩机两相流动特征的实验探索；2）超临界二氧化碳离心压缩机的数值分析与新设计方法的探索；3）多种内部两相流动的损失模型的比较和提炼。拟采取在实验测量和数值分析认识的基础上，形成新的设计方法和手段，并对内部流动的非定常现象进行诠释。主要创新之处是澄清超临界二氧化碳布雷顿循环中离心压缩机内的两相流动规律，为形成我国自有知识产权的设计技术提供理论支撑。

超临界二氧化碳布雷顿循环在太阳能热发电、核能发电及相关余热利用领域有着巨大的应用空间，已被业界专家认为是改变游戏规则的一项技术。但如何减少离心压缩机的损害提高效率，还需进一步加深认识。本项目研究思路以S-CO2离心压缩机的损失模型为切入点，寻求优化设计方法和手段。主要研究内容包括：1）S-CO2 离心压缩机的气动设计程序开发和数值模拟方法的建立与验证；2）单级和多级SCO2离心压缩机损失模型的评估；3）1MW系统S-CO2离心压缩机测试回路搭建。最终开发完成了S-CO2压缩机一维设计及分析程序，评估分析了单级和多级的压缩机损失模型，为形成我国自有知识产权的设计技术提供理论支撑。