Design And Characteristics Of Aerostatic Thrust Bearing For Antenna Gravity Compensation

In the field of space to ground wireless connection,the space borne deployable antenna plays an important role.The performance and requirements of its on orbit deployment reliability,array flatness accuracy and connection reliability are important factors for the reliable operation of the antenna and even the success or failure of the whole satellite.Therefore,a large number of simulation experiments need to be carried out on the ground to improve the deployment reliability of the space borne deployable antenna Etc.The deployable antenna is in microgravity state in space,and the high and low temperature environment in space also has a certain i MPact on the deployment of the antenna.At home and abroad,gravity compensation methods such as suspension method and air suspension method are often used to simulate microgravity environment.In this project,only normal temperature and low temperature conditions(-90℃)are considered,and air suspension method is used to simulate microgravity.Air suspension microgravity simulation system is mainly composed of air source,antenna gravity compensation device,air flotation platform and air supply pipe,and antenna gravity compensation device mainly includes Aerostatic thrust bearing,supporting mechanism,adjusting mechanism and measuring mechanism,among which aerostatic thrust bearing is an important part of gravity compensation device.The research objective of this thesis is to design a kind of aerostatic thrust bearing which can be used in antenna gravity compensation device and meet the load requirements of normal temperature and low temperature(-90℃),and analyze its static characteristics.In this thesis,the initial design of aerostatic thrust bearing in antenna gravity compensation device is completed by using engineering design method,considering normal temperature and low temperature(-90℃),then the static characteristic parameters of the bearing are simulated and analyzed by FLUENT software,and the pressure distribution,velocity distribution,temperature distribution and density distribution in the bearing film are obtained.The curves of the static characteristic parameters of the bearings calculated by the two methods have a high degree of agreement,which also verifies the correctness of the two methods.The bearing capacity under two working conditions is co MPared and analyzed.The analysis shows that the bearing capacity will be reduced under low temperature environment.Based on the parameterization of fluid grid generation,the influence of different bearing structural parameters on the static characteristic parameters(bearing capacity,stiffness and consumption flow)of the bearing is analyzed by FLUENT software,and the influence rule of different bearing structural parameters on the static characteristic of the bearing is obtained.The analysis shows that the maximum bearing capacity of the aerostatic thrust bearing mainly depends on the radius of the bearing and the radius of the distribution circle of the orifice;the diameter of the orifice has the greatest influence on the stiffness of the bearing;the diameter and number of the orifice have a great influence on the flow consumption of the bearing.The static characteristic parameters of the aerostatic thrust bearing designed in this thesis are simulated and analyzed when it is in the state of roll and cross slot.When the bearing is in the state of roll,the bearing capacity is improved;when the bearing is in the state of cross slot,the bearing capacity loss is serious.This thesis analyzes the compensation method of bearing capacity(structural glue filling the platform gap),and points out that in the actual situation,the groove formed by structural glue should be avoided,which provides a certain reference value for the ground microgravity simulation of the satellite borne deployable antenna.