缝隙引流叶片提高离心泵空化性能的机理研究

The centrifugal impeller with gap drainage blades is a new type of centrifugal pump impeller based on the idea of flow control. In recent years, studies have found that the centrifugal impeller of the new structure is not only able to improve the hydraulic efficiency of multi-operating points, but also has a great significance of anti-cavitation characteristics. As it is extremely important to improve the anti-cavitation performance of centrifugal pumps, the applicant considers it necessary to be studied in-depth. The applicant intends to carry out the research of the mechanism to improve cavitation performance of centrifugal pump with gap drainage blades through the methods of theoretical analysis, experiments and numerical simulation. The applicant plans to adopt PIV and high-speed photography to record the internal flow field of gap drainage blades centrifugal pump, and use pressure sensor and acceleration sensor to monitor the pressure and vibration of some key positions. On the basis of experimental data, the turbulence model and cavitation model for cavitation flow analysis of centrifugal pump will be established. Based on the flow field information obtained by experiments and numerical simulations, the applicant intends to study the internal mechanism to improve cavitation performance of centrifugal pump with gap drainage blades, and will establish the relationship of geometric parameters and cavitation performance parameters through the numerical parameter optimization method, then define the effect and scope of application of gap drainage blades, which will provide strong theoretical and experimental support for the design of centrifugal pumps of high anti-cavitation performance.

带有缝隙引流叶片的离心式叶轮是申请人基于流动控制的思想提出的一种新型离心泵叶轮。近年来的研究发现，此种结构的离心叶轮不仅能提高离心泵多工况点水力效率，而且能有效提高离心泵的抗空化性能。鉴于提高离心泵抗空化性能极其重要，申请人认为有必要对此现象进行深入的研究。 申请人拟采用理论分析、实验研究和数值模拟相结合的方法开展缝隙引流叶片提高离心泵空化性能的机理研究。拟采用PIV和高速摄影的方法测试缝隙引流叶片式离心泵的内部空化流流场，利用压力传感器和加速度传感器监测离心泵相关位置的压力脉动和振动信息；在实验数据验证的基础上，建立适合离心泵内部空化流动分析的湍流模型和空化模型；基于实验和数值分析获得的流场信息，研究缝隙引流叶片提高离心泵抗空化性能的内在机理，并通过参数数值优化的方法建立几何参数与空化性能参数之间的关系，明确缝隙引流叶片的效果和适用范围，为设计高抗空化性能离心泵提供有力的理论和实验支撑。

缝隙引流叶片式离心泵是基于流动控制技术研发的一种新型离心泵，实验和数值研究发现，这种离心泵在一定工况范围内不但能够提高离心泵的水力性能，而且可以有效提高离心泵的抗空化性能。项目组采用理论分析、实验研究和数值模拟相结合的方法对缝隙引流叶片提高离心泵抗空化性能的机理进行了研究。.运用PIV和高速摄影技术，测量和记录了不同工况下普通离心泵和缝隙引流叶片式离心泵内部的速度场和空化演化过程，并监测了离心泵关键位置的压力脉动和振动信号。构建包含混合RANS/LES湍流模型和基于输运方程的空化模型的数学模型。根据内流场实验、数值模拟和外特性试验的结果，经分析合理解释了缝隙引流叶片改善离心泵空化性能的机理。针对5个不同比转速的离心泵，进一步验证缝隙引流叶片结构对离心泵提高抗空化性能的有效性。.研究还表明，缝隙引流叶片在一定的工况范围还有利于抑制泵内的压力脉动，进而能改善泵的振动特性。.本项目的研究成果为设计性能优越和运行稳定的离心泵产品提供了理论支撑，具有学术价值，亦具有广阔的应用前景。