The thesis addresses the dimensioning of journal bearings, the influence of geometrical optimization with added axial grooves, and a comparison with the basic dimensioned bearing with the aim of achieving minimal friction and load. In the first part of the thesis, the theoretical background of journal bearings and the technological requirements for bearing applications are covered. Following that, we geometrically dimensioned the bearing using the Raimondi-Boyd procedure for dimensioning journal bearings, determining all the necessary parameters to minimize friction, as we are ultimately interested in the journal bearing's lifetime and efficiency. This was achieved by determining the appropriate fit between the bearing and the shaft, which defines the proper radial clearance. After the analytical determination of the parameters and maximum pressure, we performed a CFD numerical analysis to evaluate the adequacy of the analytical solutions, demonstrating that the same procedure can yield desired results even with changes in geometry. We also introduced FSI numerical analysis to monitor the loads on the bearing. The process was applied to a calculated model which resulted from the dimensioning, a practical model that is available for implementation in the final product, and an optimized model, represented by the axial groove designs. By comparing the results, we found that the optimized design positively impacts fluid pressure, resulting in lower pressures, reduced bearing stress, decreased friction, and a longer service life.
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