Prediction of the minimum oil film thickness and the maximum temperature on the surface of the bearing pad is crucial in the design and dimensioning of bearings. Friction loss, oil bath temperature and pad deflection are other parameters of interest. Depending on the desired information a numerical model requires different levels of detail. The two dimensional Reynolds equation for pressure in the oil film can be solved isothermally or considering viscosity variations in two or three dimensions, requiring solution of the equations for thermal equilibrium in oil and pad. Knowing the temperature distribution the deflection of the pad due to pressure and thermal bending can be calculated using a flat plate approximation. At the five free sides of the pad heat transfer can be modelled. The temperature distribution at the inlet to the pad can be calculated through equilibrium of thermal energy for the groove between pads and the oil bath temperature from energy equilibrium for the entire bearing. The main theoretical contribution of this paper is the elaboration and comparison of 7 different mathematical models of increasing complexity. The results are compared to experimental data for steady-state operation of a 228 mm outer diameter bearing. It is found that for the given bearing a two dimensional model is sufficient to estimate the minimum oil film thickness and the maximum temperature on the pad surface. Three dimensional modelling does not improve the quality of the results.
|Title of host publication||Proceedings of the 18th International Congress of Mechanical Engineering (Cobem 2006), Ouro Preto, Brazil, 6-11 November|
|Publication status||Published - 2005|
|Event||18th International Congress of Mechanical Engineering (Cobem 2006) - Ouro Preto, Brazil|
Duration: 6 Nov 2005 → 11 Nov 2005
Conference number: 18
|Conference||18th International Congress of Mechanical Engineering (Cobem 2006)|
|Period||06/11/2005 → 11/11/2005|