The analysis of thermal effects is of expressive importance in the context of rotordynamics to evaluate the behavior of hydrodynamic bearings because these effects can influence their dynamic characteristics under specific operational conditions. For this reason, a thermohydrodynamic model is developed in this work, in which the pressure distribution in the oil film and the temperature distribution are calculated together. From the pressure distribution, the velocity distribution field is determined, as well as the viscous dissipation, and consequently, the temperature distribution. The finite volume method is applied to solve the Reynolds equation and the energy equation in the thermohydrodynamic model (THD). The results show that the temperature is higher as the rotational speed increases due to the shear rate of the oil film. The maximum temperature in the bearing occurs in the overloaded pad, near the outlet boundary. The experimental tests were performed in a tilting pad journal bearing operating in a steam turbine to validate the model. The comparison between the experimental and numerical results provides a good correlation. The thermohydrodynamic lubrication developed in this assignment is promising to consistently evaluate the behavior of the tilting pad journal bearing operating in relatively high rotational speeds. 1. Introduction Aiming to increase profits and improving economic growth, the industries have been seeking for some ways to raise productivity, such as new technologies, system optimization, and consequently, power source increasing. Those factors allow the machines operation in higher speed accelerating the production system. However, the increment of the operational speed, specifically in rotating machinery, is not a simple task, because it can cause serious problems like affecting the safe operational conditions of the machines. The rotation speed increase in rotating machines can completely change its dynamic behavior, turning an initially stable machine into an unstable one. It mainly occurs due to the dynamic characteristics of the bearing, which tends to change significantly with the rotational speed. One of the reasons is the influence of thermal effects in high rotational speed, because of the shear rate in the oil film, increasing consequently the temperature of the lubricant as well. Therefore, special attention must be taken due to the influence of the thermal effects in the hydrodynamic bearings under certain operational conditions. An article of valuable contribution to the development of thermohydrodynamic analysis
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