混流式核主泵内部流动及其控制

The internal flow and control in mixed-flow nuclear coolant pump (RCP) is one of key problems for the RCP development in large pressurized water reactor. The internal flow in a mixed-flow model pump with a typical specific rotating speed is studied in this project. Flow pattern and unsteady phenomena are investigated by advanced flow measurement technologies and numerical simulation using LES. Energy transfer mechanism between hydraulic parts and fluid are considered as the core content. Radial and axial flow dynamics in the mixed-flow impeller are analyzed using vortex and cascade theory.Flow field is discussed in the radial guide vanes and torispherical casing.The effective approach to flow control in the pump is studied purposeful by energy analysis and vortes dynamic flow diagnosis.This project is about to reveal the real flow structure in the mix-flow RCP, to find the pushing fuctions under the new energy transfer model.Flow rate distribution and loss model will be built in the guide vanes and casing.New approach to successful flow control in RCP is hoped to be found out.Research findings will have a new annotation on the internal flow mechanism in RCP. They will lay the foundation of RCP hydraulic parts innovation with independent intellectual property rights, and provide theoretical support on the RCP development with high efficiency and stability as well.

混流式核主泵内部流动及其控制是大型压水堆核主泵研制中的关键问题。本项目以具有代表性比转速的模型泵内部流动为研究对象，运用先进的流场测量技术和基于LES的数值计算方法探索混流式核主泵内部典型流谱及非定常流动特征。以研究泵内水力部件与流体能量传递、转化机制为核心内容，深度剖析基于旋涡理论、叶栅理论的混流式叶轮内叶片与流体相互作用后的径向、轴向动力学特性，探讨径向导叶与准球形壳体组合后的流动匹配问题，从能量角度结合优秀的涡动力学流场诊断方法，有目的性地探索泵内流动的有效控制途径。试图揭示混流式核主泵内真实的流场结构，推导混流式叶轮内新的能量传递模型下的推动系数，建立导叶和壳体内的流量分配及能量损失模型，初步形成主泵内部流动控制新思路。项目研究成果将对混流式核主泵内部流动机理作出新诠释，为实现具有自主知识产权的主泵水力模型原始创新奠定基础，也为高效、稳定的核主泵研制提供理论支撑。

核主泵内部流动及其控制是我国自主研制核主泵技术中的关键问题。本项目创新性地提出以实现核主泵内部流动有效控制为目标，综合运用理论分析、LES数值计算方法和压力脉动测试、PIV、LDV流场测量等试验手段，系统深入地研究核主泵内复杂流动机理，并阐明了该泵的非稳态流动激励机制。重点分析动静干涉对该泵流动稳定性的影响，将非稳态流动结构的复杂演变过程与激励特性进行关联分析，描述了非稳态流动结构，揭示了关键激励因素及不同非稳态流动结构对压力脉动的影响规律。探讨了径向导叶与准球形压水室的流动匹配特性并且在导叶出口连接导流环，建立了导叶与压水室内的流量分配模型及能量损失模型，得出了合适的匹配布置方式不仅能够改善流场而且可以提高整泵的水力效率。基于已掌握的泵内流动规律，探索了混流叶轮径向与轴向分解方式，并定义径向与轴向推动系数，尝试同时用各系数描述叶片对流体的做功贡献，从而重新认识其能量传递机制。对泵内水力部件进行流动控制初步探索，研究了不同叶轮与导叶的主要参数对泵能量性能、压力脉动及不稳定内流结构的影响。发现通过改进叶片尾缘形状在提高泵水力效率的同时，能有效抑制流动分离和尾迹结构。研究成果对核主泵内部流动机理作出新诠释，为实现具有自主知识产权的核主泵水力模型原始创新奠定基础，也为高效稳定的核主泵研制提供理论支撑。