自激离心式空化反应器的空化及压力脉动特性研究

Cavitation and pressure pulsation characteristics of self-excited centrifugal cavitation reactor

水力空化产生的高温高压环境能够用于杀菌消毒、乳液制备和冲击破岩等。针对广泛存在于流体机械中的水力空化现象,提出一种新型旋转式水力空化反应器,以该反应器作为研究对象,基于Zwart-Gerber-Belamri空化模型和Realizable k-ε湍流模型,分别对3种不同转速下的非稳态空化流场进行了数值模拟,考察了其空化与压力脉动特性的相互作用关系,分析反应器内部压力脉动发展规律以及转速对转子叶轮区域空化性能的影响,为后续空化机理的研究提供了理论依据。结果表明,随着转速的增大,转子区域的空化强度和空化面积迅速增大;压力脉动的叶频幅值呈现明显的周期性变化。

The high-temperature and high-pressure environment generated by hydrodynamic cavitation can be used for sterilization,emulsion preparation and impact rock breaking.A new type of rotary hydrodynamic cavitation reactor is proposed according to the hydrodynamic cavitation phenomenon widely existing in fluid machinery.The reactor is taken as the research object.Based on the Zwart-Gerber-Belamri cavitation model and the Realizable k-εturbulence model,the numerical calculation of the unsteady cavitation flow field at three different rotational speeds is carried out.The interaction relationship between cavitation and pressure pulsation,the development law of pressure pulsation inside the reactor and the influence of rotational speed on the cavitation performance of the rotor impeller region are analyzed,which provide a theoretical basis for the subsequent research on the cavitation mechanism.The results show that the cavitation strength and cavitation area in the rotor region increase rapidly with the increase of the rotational speed,and the the blade frequency amplitude of the pressure pulsation shows obvious periodic changes.