Energy equation of aerostatic thrust bearing under the effect of inertia force

To simplify the mathematical model of gas thrust bearing with larger clearance,the energy equation of three-dimensional gas thrust bearing under the effect of inertia force was derived by using dimensional analysis method,and the relation between temperature and Mach number was obtained.It is demonstrated from the relation that the temperature in gas film is relevant to Mach number when the wall temperature is constant.The temperature in the film drops quickly with Mach number increasing sharply while the temperature goes up fast with Mach number decreasing rapidly.The lowest temperature in the passage is 20% lower than the wall temperature when Mach number is 1.The gas temperature lowers down only a bit though the increase of gas velocity leads to the decrease of its temperature when the gas flow in the passage is sub-sonic,and thus the change of its temperature can be neglected when the dynamic and static parameters are approximately calculated.The CFD software was used to calculate pressure distribution,temperature distribution and Mach number distribution in the film with larger clearance,and the results show that the theoretical values matches well with the experimental values.