In vertically oriented machines with journal bearing, there are no predefined static radial loads, such as dead weight for horizontal\r\nrotor. Most of the commercial software is designed to calculate rotordynamic and bearing properties based on machines with\r\na horizontally oriented rotor; that is, the bearing properties are calculated at a static eccentricity. For tilting-pad bearings, there\r\nare no existing analytical expressions for bearing parameters and the bearing parameters are dependent on eccentricity and load\r\nangle. The objective of this paper is to present a simplified method to perform numerical simulations on vertical rotors including\r\nbearing parameters. Instead of recalculating the bearing parameters in each time step polynomials are used to represent the bearing\r\nparameters for present eccentricities and load angles.Numerical results are compared with results fromtests performed in a test rig.\r\nThetest rig consists of two guide bearings and a midspan rotor.Theguide bearings are 4-pad tilting-pad bearings. Shaft displacement\r\nand strains in the bearing bracket are measured to determine the test rig�s properties. The comparison between measurements and\r\nsimulated results shows small deviations in absolute displacement and load levels, which can be expected due to difficulties in\r\ncalculating exact bearing parameters.
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