Helmholtz喷嘴结构参数对空化射流特性的影响

自振空化射流是在射流过程中利用喷嘴内部结构的振荡特性产生空泡，在射出喷嘴后空泡发 生溃灭来增大射流冲击作用的现象。由于自振空化射流效果与喷嘴结构有密切关系，因此近年来关于 喷嘴结构的优化研究广受关注。鉴于 Helmholtz 喷嘴在增强射流冲击力方面具有明显优势，该文针对 不同结构参数的 Helmholtz 喷嘴的内外流场进行了数值仿真，重点分析了出口直径、出口长度、共振 腔空化长度、共振腔空化直径等关键结构参数及射流靶距对空化水射流效果的影响，相关研究成果可 为空化射流船舶清洗技术提供理论指导。

Effects of Structural Parameters of Helmholtz Nozzle on Cavitating Jet Characteristics

Self-oscillating cavitating jet is a phenomenon in the process of jet flow. The cavitation is produced by the oscillation characteristics of the internal structure of the nozzle. And the cavitation collapses after it is ejected from the nozzle, which enhances the impact force of the water jet. The selfoscillating cavitating jet effect is related to the nozzle structure. Since Helmholtz nozzle has great advantage in enhancing the jet impacting force, this paper investigates the flow fields inside and outside of the Helmholtz nozzle with different structural parameters based on numerical simulation, and this paper mainly analyzes the influence of some key structural parameters, including the outlet diameter, the outlet length,the resonant cavitating length, the resonant cavitating diameter and the target distance, on the cavitating jet performance, and the results can provide a theoretical instruction for the applications like the caviating jet technology in ship cleaning.