自振射流装置结构及频率特性  

Device Configuration and Frequency Characteristics of Self-resonating Water Jet

作　　者：潘岩[1] 蔡腾飞[1] 马飞[1] 邱林宾 高路路[1] PAN Yan;CAI Tengfei;MA Fei;QIU Linbin;GAO Lulu(School of Mechanical Engineering,University of Science and Technology Beijing,Beijing 100083)

机构地区：[1]北京科技大学机械工程学院,北京100083

出　　处：《机械工程学报》2020年第12期207-213,共7页Journal of Mechanical Engineering

基　　金：国家自然科学基金(51774019);国家重点研发计划(2016YFC0802900)资助项目。

摘　　要：自振射流频率特性包括低频脉动与高频振荡,其发生机理与应用条件均存在较大差异,而现有研究较少。基于流体网络理论建立数学模型,分别计算流体管网与喷嘴的声谐固有频率;基于信号分析方法,获取自振射流的全频谱结构,进而探讨射流装置结构与射流频率特性的关系。试验结果表明,一个完整的自振射流频谱由低频脉动和高频振荡两部分组成,但两者相差近两个数量级;自振射流的低频脉动通常由管网内流体扰动引发,当扰动频率与管网固有频率相接近时,低频振荡增强;其高频振荡由喷嘴出口处流体涡激振动引发,当涡振频率与喷嘴声谐固有频率相接近时,射流产生强烈的高频振荡;低频脉动射流不受喷嘴出口形状和外部环境参数影响,可应用于非淹没或低围压环境下,而高频振荡射流受喷嘴出口形状和外部环境参数影响大,可应用于围压条件下。研究成果揭示了射流装置结构与射流频率特性的关系,为自振射流装置结构设计及深海资源开采提供了技术支撑。The frequency characteristics of self-resonating water jet include low-frequency pulsation and high-frequency oscillation,the occurrence mechanism and application conditions of which are quite different,while it is less reported.The device producing the jet is regarded as a whole,based on the fluid network theory,the mathematical model of the device is established to obtain the acoustic natural frequencies of the fluid network and the nozzle.Based on the signal analysis method,the whole frequency spectrum of the self-resonating jet is obtained,then the relationship between the device configuration and the frequency characteristics of the jet is discussed.The experimental results show that a complete spectrum of the self-resonating water jet consists of two parts,namely the low frequency pulsation frequencies and the high frequency oscillation frequencies,but the difference between these two frequency ranges is nearly two orders of magnitude.The low frequency pulsation of the self-resonating water jet is usually caused by the fluid disturbance inside the pipe network,when the disturbance frequency is close to the acoustic natural frequency of the pipe network,the low-frequency oscillation is enhanced.While the high-frequency oscillation is caused by the vortex-induced vibration at the nozzle exit.When the vortex shedding frequency is close to the acoustic natural frequency of the nozzle,the acoustic resonance occurs and the high frequency oscillation is generated.The low frequency pulsating jet is not affected by the shape of the nozzle outlet and external environmental parameters,so it can be applied to non-submerged or low confining pressure environments,while the high frequency oscillating jet is strongly affected by the above factors,so it can be applied under confining pressure conditions.The research results reveal the relationship between the device configuration of the self-resonating water jet and the frequency characteristics of the jet,which provides a theoretical basis for the structural design of the

关 键 词：自振射流 装置结构 频率特性 低频脉动 高频振荡 

分 类 号：TG156[金属学及工艺—热处理]