Theoretical Characteristics of Hydrodynamic Journal Bearings lubricated with Air Helium Mixture
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Abstract
This paper presents the theoretical hydrodynamic lubricating characteristics of air-helium gas mixture in journal bearings under a steady-state condition. The method is using Finite Difference Method and Newton Raphson Method to solve the Modified Reynolds equation without considering the temperature change effect of the lubricant film on the surface of the round shaft. From the simulation results, it was found that when the air-helium gas mixture ratio and the shaft rotation speed increased, the maximum film pressure and the maximum eccentricity decreased as a consequence while the minimum film thickness and the angle position at the minimum film thickness increased. On the contrary, when reducing the air-helium gas mixture ratio and the rotational speed of the shaft, the maximum film pressure and maximum eccentricity increased while the minimum film thickness and the angle position at the minimum film thickness decreased. When increasing the load on the shaft, the maximum film pressure increased while the minimum film thickness decreased giving the same results as when using air and air-helium gas mixtures as lubricants.
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