【作者】 陈辉；

【导师】 肖望强；

【作者基本信息】 厦门大学 ， 机械工程， 2022， 硕士

【摘要】 离心式空调冷水机组作为一项新型的高效空调技术,由于其具有节能效率高、负载性能卓越、使用寿命长等优点近年来引起了诸多关注。冷水机组作为空调的核心设备,在各行各业应用广泛。然而,离心式冷水机组在运行过程中产生的振动将直接影响其运行安全,当机组的振动强度超过一定值后,将会影响相关设备的精密度,恶化设备结构应力,影响设备使用寿命,甚至由于振动传递到设备终端,对安装环境造成振动损害,降低工作环境的舒适性。因此,对离心式空调冷水机组进行减振研究尤为必要。在冷水机组上安装粒子阻尼器,通过阻尼粒子集合间力链的断裂与重组形成的阻尼效应可以有效的控制机组的振动。粒子阻尼器布置灵活,对温度和环境变化不敏感,适合在恶劣环境下使用,可靠性高。同时,粒子阻尼器可以在多个方向和更广泛的频率范围内工作,对原结构的改动较小,适合在冷水机组等狭窄空间中使用。本文首先对冷水机组进行振动分析,对机组整机进行了振动测试,分析了机组的振动来源,对机组压缩机、管路、筏架进行具体分析,得出机组的振动传递路径。随后对机组进行模态和谐响应分析,得到机组的模态敏感区域和位移响应,最终获得整个机组的振动敏感区域,确定了粒子阻尼器的安装位置。之后,设计了冷水机组用粒子阻尼器,基于离散单元法,对粒子阻尼器参数进行了优化,分析了阻尼粒子的材质、粒径大小以及阻尼器布置方式对冷水机组减振的影响,最终获得阻尼器的最优参数。最后,搭建实验平台,制造并安装了粒子阻尼器,对装有最优参数阻尼器的冷水机组进行减振实验,使其达到指标要求。根据实验结果,机组在安装最优参数的粒子阻尼器后,冷水机组在以额定工况运行时(运行频率386Hz),压缩机机脚各测点的平均减幅为5.49dB;整机机脚各测点平均减幅为8.95dB。机组在以低速工况运行时(运行频率为300Hz),压缩机机脚各测点的平均减幅为5.1dB;整机机脚各测点平均减幅为9.78dB,减幅均超过指标要求,减振效果明显。本文为粒子阻尼技术运用于冷水机组的振动控制提供了重要指导。更多还原

【Abstract】 As a new high efficiency air conditioning technology,centrifugal chiller has attracted much attention in recent years because of its advantages of high energy saving efficiency,excellent load performance and long service life.As the core equipment of air conditioning,chiller is widely used in all walks of life.Centrifugal water chillers,however,in the process of running vibrations will directly affect the safe operation,and after the vibration intensity exceeds a certain value of the unit,will affect the precision of the related equipment,deteriorating equipment structure stress,affect the service life of the equipment,even due to the vibration transmitted to the terminals,vibration damage to the installation environment,reduce the working environment of comfort.So,it is very necessary to research the vibration reduction of centrifugal air conditioning chiller.The vibration of the chiller can be controlled effectively by the damping effect formed by the fracture and recombination of the force chains between the damping particles by installing a particle damper on the chiller.The particle damper is flexible,insensitive to temperature and environmental changes,suitable for use in harsh environment,high reliability.At the same time,the particle damper can work in multiple directions and a wider frequency range,with little modification to the original structure,suitable for use in narrow Spaces such as water chillers.In this paper,first of all,vibration analysis of the chiller,vibration test of the whole unit,analysis of the vibration source of the unit,compressor,pipeline,raft frame specific analysis,the vibration transmission path of the unit.Then the modal harmonious response of the unit was analyzed to obtain the modal sensitive area and displacement response of the unit,and finally the vibration sensitive area of the whole unit was obtained,and the installation position of the particle damper was determined.After that,the particle damper for chiller was designed.Based on discrete element method,the arguments of the particle damper were optimized,and the influence of the material,particle size and the arrangement of the damper on the vibration reduction of chiller was analyzed.Finally,the optimal parameters of the damper were obtained.In the end,the test platform was built,the particle damper was manufactured and installed,and the vibration reduction experiment was carried out on the chiller equipped with the optimal parameter damper to make it meet the requirements of the index.According to the experimental results,after the installation of the particle damper with optimal parameters,the average amplitude reduction of each measuring point of the compressor foot is 5.49dB when the chiller runs at rated operating condition(operating frequency 386Hz).The average amplitude reduction of each measuring point of the machine foot is 8.95dB.When the unit is running at low speed(running frequency is 300Hz),the average amplitude reduction of each measuring point of the compressor foot is 5.1 dB.The average amplitude reduction of each measuring point of the machine foot is 9.78dB,which exceeds the requirement of the index,and the effect of vibration reduction is obvious.This paper provides important guidance for the adhibition of particle damping technology in vibration control of chiller.更多还原