复杂工况下压力能传递的压力波动与叠加强化机制研究

Rotary pressure exchanger transfers the pressure energy between two liquids by bringing the streams into and direct contact in the ducts of a rotor.It has been applied in seawater desalination plants, and also shows a great potential in chemical industries where more fluids pressure energy can be recovered.Pressure energy recovery process would be influenced by various fluids properties such as pressure, temperature, concentration, and impurity ratio. Some dynamic conditions including cavitation, flash evaporation or sedimentation may also exist during pressure energy transfer process. This project intends to discover the pressure transfer characteristics under complicated work conditions. Combining with the wave equations solved by the method of characteristics and the flow field simulation using CFD methods, experimental research is used to support each other and get better results. This project reveals the basic propagation regularity of pressure wave, and disclosures the influence mechanism of operation conditions, physical properties and structure parameters, and then proposes the supercharger methods considering the pressure wave superposition, utilization of cavitation collapse and drag reduction. After investigating the quantitative relationship between the pressure wave propagation characteristics and pressure recovery effect, the integrated strategy of fluids pressure energy recovery in chemical process is established. This project contributes to deep understanding of pressure energy transfer and strengthening mechanism, and lays the foundation for the extending application of pressure exchange technology in chemical industries and device design.

旋转容积式压力能交换器已在反渗透海水淡化领域成功应用，其中两股流体直接接触高效传递压力能，节能效果显著。化工领域存在大量的流体压力能资源，回收潜力巨大。但化工过程不同流体间压力、温度、浓度、杂质组分等参数差异悬殊，传递过程可能伴随气穴、闪蒸及杂质淤积等现象。本项目针对复杂化工背景下压力能传递中瞬变流压力波动现象，利用特征线法求解波动方程组，结合CFD方法模拟流动特征，并利用压力能传递实验进行验证，评价物性、操作及结构参数对压力能回收效果的影响，揭示更为普遍的压力波动规律。项目还探讨压力能传递过程中压力波叠加、空泡溃灭时压力脉冲、摩擦减阻等能量回收强化机制，获得压力波动特性与压力能回收效果间的定量关系，建立实际化工流体间压力能回收综合策略。本研究有助于深化对液体压力能传递的核心机理与强化机制的认知，为开拓其在化工领域的实际应用、指导装置设计奠定基础理论，具有重要的学术意义和工程价值。

旋转式压力能交换器（Rotary Pressure Exchanger，RPE）两股流体直接接触高效传递压力能，在化工领域有巨大的应用潜力。本项目从功量交换过程的压力波动、压力波与压力能回收的内在关系、压力能传递过程强化三方面开展研究，揭示了压力能传递的核心机理。.项目构建了压力能回收过程的数值模型，探讨了RPE装置的流态划分、流型特性及掺混控制方法，分析了盘式和滑片式RPE装置的压力能回收特性。设计了可控旋转式压力波发生器，建立了三维旋转式压力波发生器的数值模型，探讨了压力波的产生机理。针对RPE孔道内压力波动问题，利用WENO格式进行求解，得到了孔道内一维压缩波与膨胀波的传播、反射和叠加过程，以及孔道内转子转动各过程中压力波动特性，获得了孔道内压力波的传播规律。.对于具有复杂瞬变工况下的余压回收管网系统，提出了利用多物理场耦合特性的设备管网跨尺度计算方法，实现了管网系统的动态仿真。针对阀门瞬变操作工况，研究了瞬变操作对管线内余压回收装置压力波传播的影响，获得了压力波在管网-设备体系内的传递规律。搭建了压力能回收系统实验台，设计了孔道可视化的RPE结构，对孔道内的不稳定性流场开展可视化实验，研究发现孔道内会出现不稳定性旋涡结构，从而加剧了流体的扰动和流体间的掺混。.项目提出了自增压RPE装置，采用最优波系分析方法探讨了不同波系反射结构的RPE性能随工况的变化，获得了压力波反利用的波系叠加增压理论。提出了热法-膜法耦合制水系统，发现耦合系统有更好的系统性能和可调节性。提出了热-功耦合回收的网络集成优化方法，得到了热-功耦合回收的优化网络匹配方案。针对含杂质的功量交换过程，研究了颗粒杂质在非稳定流动中的运动特性。考察了被动控制技术对有限通道内拟序涡的抑制作用，发现分隔板控制技术能有效抑制旋涡的形成与脱落。