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Performance Characteristics for Hydrostatic Thrust Bearing of a Saw Blade

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Abstract

A semi-analytical solution is presented to obtain the pressure distribution, the load capacity, the frictional moment and the lubricant flow rate for a laminar flow, hydrostatic bearing with its axis offset from thee axis of the saw blade. The general equations are developed and solved for a variable film thickness due to plate vibrations. It was found that the load, friction and lubricant flow rate are strong functions of film thickness variations ϵ, bearing number λ and the bearing offset from the rotation axis

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... The available studies in literature clearly reveals that consideration of both lubricant behavior as well as tilt is very important to generate the realistic design data [7,26,30,31]. No study in the literature has yet been reported that demonstrates the behavior of thrust bearing operation with Rabinowitsch lubricant with tilt consideration. ...
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The performance characteristics of capillary compensated tilted pad hydrostatic bearing operating with Newtonian lubricant and cubic law lubricant are studied numerically considering the flexibility of pad. The two-dimensional Reynolds equation coupled with three-dimensional equilibrium equations governing the deformation of thrust pad has been solved by using finite element method. The results indicate the influence of tilt parameter and bearing deformation on bearing performance characteristics parameters. In the analysis, four different types of recess shapes such as rectangular, circular, elliptical, and square have been chosen for the analysis. The results show that the consideration of bearing pad deformation significantly increases the value of fluid-film stiffness coefficient and decreases the value of fluid-film damping coefficient. The fluid-film pressure distributions also compared for circular, elliptical, square, and rectangular bearing.
... Under non-axisymmetric condition, cavitations may occur due to wedge action generated by shaft rotation. Safar (1980) worked on the performance of circular step hydrostatic thrust bearing under non-axisymmetric condition of operation by assuming full film condition and did not investigate on the cavitations effect. ...
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