Design Theory And Experiment Of Circular Thrust Bearings In High Supply Pressure

Gas bearing has the advantages of high rotation precision,low coefficient of friction,high positioning accuracy,minimal frictional wear and long service life,but the traditional externally pressurized gas bearing also has the disadvantages of low supply pressure,capacity and stiffness,it can be only used for light load and precision support.However,the development of modern advanced industrial technology needs the gas lubricated bearing which has high pressure and heavy load urgently.The capacity of the gas bearing depends on the flow state in the bearing clearance,also the flow state in the clearance is closely related to the bearing structure.Referring to the design theory of contraction cone of wind tunnels,a new type of high pressurized circular thrust bearing with disymmetric contraction cone is proposed,with the structural design of flow channel,the internal flow field of the bearing can be improved,and the limitation of supply pressure can be eliminated.The main research contents of this paper are as follows:1.A mathematical model for the flow of the disymmetric contraction cone based on the incompressible potential flow is established,with the results of the characteristics of outlet flow field in the contraction cone calculated by MATLAB,the feasibility of the proposed design method is preliminary verified.2.The internal flow field of high pressurized circular thrust bearing with disymmetric contraction cone is simulated by Fluent based on compressible turbulent model,with the comparison between the results of the characteristics of outlet flow field in the contraction cone simulated by Fluent and the results calculated by MATLAB,the feasibility of the proposed design method is verified further.3.The characteristics of internal flow,the distribution of the pressure,the Reynolds number,the mass flow and the load capacity of high pressurized circular thrust bearing with disymmetric contraction cone are analyzed and compared in different structures and operating conditions.The theoretical and numerical results show that: under the conditions of highsupply pressure and large bearing clearance,there is a steady and uniform flow field in the clearance of the high pressurized circular thrust bearing with disymmetric contraction cone,and the shortcoming that the capacity of bearing is limited to the supply pressure can be overcame,and the capacity can be increased linearly with the supply pressure.