Performance Analysis And Rotor Dynamics Analysis Of Liquid Metal Radial Grooved Bearings For CT Ball Tubes

CT as an important medical equipment,X-ray tube is the core component,its function is to produce medical diagnostic X-ray,and its performance directly determines the imaging level of lesions.The service life of traditional CT ball tube is low,and the bearing used is the main factor limiting its service life,and its accuracy and performance also directly affect the imaging,noise and stability of CT equipment.Liquid metal grooved bearing has almost zero wear and good heat conduction effect,so its application in CT tube has become the first research technology in the medical equipment industry.The use of liquid metal grooved bearing can greatly improve the contact area between the bearing bush and the rotating shaft,and greatly improve the efficiency of heat transfer from the anode target plate to the bearing support system.Compared with ball bearings,under the same conditions,liquid metal grooved bearings can improve the heat capacity of the anode assembly by 10% to 20%,and the anode heat dissipation efficiency by about 50%.At present,the research,test and application of liquid metal grooved bearings are mostly concentrated in foreign countries,and are still in the development stage of research in China.On the basis of previous studies,On the basis of previous studies,this paper does the following work:(1)Summarize the development history and future development trend of CT ball tube at home and abroad for more than 100 years,the structure of CT ball tube,and discuss the application of liquid metal grooved bearings in CT ball tube;(2)Aiming at the practical application of liquid metal grooved bearings in CT tubes,the lubrication theoretical model of liquid metal grooved bearings was established in this paper.The gas lubrication equation was discretized by the finite difference method,and the Simpson integral method was used to solve the bearing pressure distribution and capacity.(3)The static and dynamic characteristics calculation model and solving process were established,and the corresponding theoretical calculation program was written based on MATLAB to study the differences of liquid metal grooved bearings compared with ordinary plain bearings.By changing the bearing structural parameters and working conditions,the static and dynamic characteristics of liquid metal grooved bearing under different conditions are analyzed and compared,which provides a feasible reference and optimization direction for bearing design and test.(4)By exploring the solution method of the shafting rotor dynamics equation,the dynamics characteristics of the structure with different coaxial system arrangement are simulated based on XLRotor software,and the rotor dynamics characteristics are studied by analyzing the Campbell diagram and the undamped critical speed diagram of the bearing-rotor system by using the characteristic root solution and unbalance response calculation.It provides theoretical reference for structure design and life evaluation of liquid metal slotted bearings in CT ball tubes.