Research On Loading Characteristics Of Hybrid Gas Thrust Bearing

Hybrid gas thrust bearing is a new type of bearing based on hydrodynamic bearing and hydrostatic bearing. It combines the advantages of hydrodynamic bearing and hydrostatic bearing, but overcomes the disadvantages of them to a large extent. Before the rotor starts, compress gas into the bearing gap through the restrictor, resulting hydrostatic bearing capacity. When the rotor starts on high speed, dynamic pressure effect brings dynamic pressure bearing capacity, and provides gas membrane force with hydrostatic bearing capacity. It’s effective to avoid solid contact friction and prolong the life of the bearing, and reduce continuing high pressure gas at the same time.To study the characteristics of hybrid gas thrust bearing, this paper establish the simulation model of spiral grooves s hybrid gas thrust bearing which is based on the previous design through FLUENT. It’s different of hybrid gas thrust bearing and hydrodynamic bearing and hydrostatic bearing in boundary conditions on the simulation, which require a variety of ways to try and determine. Next, this paper compares bearing capacity between hybrid gas thrust bearing and the sum of hydrodynamic bearing and hydrostatic bearing and analyses the reason of decline of hybrid gas thrust bearing’s capacity. According to the simulation results, this paper proposes an assumption that there is pressure leak on the hole.Compared the capacity with each other under different operating conditions, it’s easy to get the curves of carrying capacity, bearing stiffness and inlet flow vary with the gas film thickness. Analysis of the influence of supply pressure, speed and the thickness of the gas film to the characteristics verifies the assumptions of the the pressure relief phenomenon. It is necessary to avoid this phenomenon, because under this condition the the bearing have large stiffness but poor carrying capacity, and it can’t achieve better load carrying characteristics.Finally, building the hydrodynamic thrust bearing bench, this paper studies the affect of supply pressures, speed and gas film thickness to the bearing capacity by experimental methods, and compares and verifies the experimental results with that of the simulation. The characteristics curve of hydrodynamic thrust bearing bearing in this paper may provide some reference.