Vibration Analysis And Control Of Stirling Cryocooler

Stirling cryocooler is mainly used in infrared system, its key role is to providelow-temperature environment for the focal plane detector installed in the cold head.Stirling cycle refrigeration is used by Stirling cryocooler, the driving force comesfrom the linear motor, but it brings reciprocating movement along the refrigerantaxial, thus causing the axial vibration of the stirling crycooler. When the vibrationexceeds a certain amplitude, it could seriously affect the imaging effects of thefocal plane,which cause the focal plane detector working badly. Therefore,thiskind of vibration must be controlled in order to improve its performance.This paper mainly carry out preliminary studies and analysis of thecryocooler vibration control of an engineering company， some correspondingsolutions have been achieved. Firstly, the theoretical analysis of cryocoolervibration is carried out in order to find out the possible reasons of the vibration.Secondly, the vibration of cryocooler under different working status is tested, andthe actual vibration situation of cryocooler is obtained. Cryocooler vibrationcontains fundamental frequency of60Hz and a large number of harmoniccomponents. Compared whit the fundamental frequency, harmonic componentsoccupy a small proportion relative, but harmonic vibration must be consideredwhen the vibration control requirements reach a certain level. Aimed at controllingthe vibration of60Hz, the dynamic vibration absorber has been designed andoptimized by using the finite element analysis of workbench, and it works very well.Additionally, harmonic vibration control has been researched preliminarily, and aspecific program for the twice harmonic control is proposed.The periodicity goal of this study has accomplished, the cryocooler vibrationanalysis and design process of the dynamic vibration absorber have some certainsignificance for practical engineering applications.