112 FEM MODELLING AND CHARACTERISTICS RESEARCH OF CYLINDRICAL JOURNAL BEARING FOR CONE INERTIAL CRUSHER /KID - 300/ Petko NEDYALKOV Technical University of Sofia, Bulgaria Abstract. This article presents finite element modeling and simulation analysis of vertical cylindrical journal bearing for cone inertial crusher (KID-300). The research is done through changing different technical and constructive bearing parameters. There is obtained results about pressure distribution and power losses in the bearing. Throughout analysis of those results, determinates the most suitable working regime for the bearing according to minimization of the power loses in the bearing. The presented research methodic is suitable for examination of bearing behavior in different working regimes of the crusher. Keywords: cylindrical journal bearing, simulation study, finite element modelling 1. Introduction In previous work [3] is developed and described a methodic for analytical calculations of basic bearing parameters for vertical cylindrical journal bearing used in cone inertial crusher (KID 300). Cone inertial crusher [2] is a stone crusher for middle to fine size crushing of mineral materials with dynamical excitation. The vertical journal bearing is a problematic assembly of the crusher through different speed and force regimes of the crusher. According to analytical methodic [3] in this paper is presented the simulation methodic for research ad analysis of different bearing regimes. The results of FEM simulation is processed and analyzes with statistical instruments and it is developed a mathematical model described those parameters. 2. Research parameters and factors The research is focused over the following parameters: - pressure distribution in the cylindrical bearing; - mechanical power loses in the cylindrical bearing according to the sliding friction. Those bearing parameters depend on the changing the following factors: - angular velocity - ωd [rad/s] - of the bearing bush witch holds the unbalanced excitator of the crusher. Angular velocity is changed in the different working regimes of the crusher; - dynamical viscosity - µ [N⋅s/m 2 ] - of the lubrication oil. Dynamical viscosity of bearing is temperature dependent and with the heating of the machine it is changing; - lubrication system mass flow capacity - Qm [kg/s]. This parameter is changing through oil filters contamination, oil contamination and inappropriate oil pump regulation. Simulated regimes corresponds with the analytical research [3, 4, 5] and also there is accounted the factors concerning ordinary usage of the crusher and bearing assembly, as following: - surface roughness - ε [µm]. This factor is changing due to improper exploitation of the bearing assembly, usage with contaminated oil and usage of unsuitable oil and also due to starting regimes with unstable oil lubrication in the journal. There is used the sand grain roughness equivalency parameter noted with ε. Connection between sand grain roughness ε and average peak roughness Rz according [1] is ε = 0.978⋅Rz [µm]. - bearing clearance - s, mm. This parameter is changing due to bearing damage and repair through moving in the different repair dimensions. 3. FEM model setup and creation Figure 1 presents axial section of the cylindrical journal bearing with flow boundaries and geometrical parameters - the bush length and clearance. Figure 1. Cylindrical bearing situation and boundaries