The Response of a Spherical Journal Bearing to Rotor Unbalance

In high speed, high load fluid-film bearings, the laminar-turbulent flow transition can lead to a considerable reduction of the maximum bearing temperatures, due to a homogenization of the fluid-film temperature in radial direction. Since this phenomenon only occurs significantly in large bearings or at very high sliding speeds, means to achieve the effect at lower speeds have been investigated in the past. This paper shows an experimental investigation of this effect and how it can be used for smaller bearings by optimized eddy grooves, machined into the bearing surface. The investigations were carried out on a Miba journal bearing test rig with Ø120 mm shaft diameter at speeds between 50 m/s–110 m/s and at specific bearing loads up to 4.0 MPa. To investigate the potential of this technology, additional temperature probes were installed at the crucial position directly in the sliding surface of an up-to-date tilting pad journal bearing. The results show that the achieved surface temperature reduction with the optimized eddy grooves is significant and represents a considerable enhancement of bearing load capacity. This increase in performance opens new options for the design of bearings and related turbomachinery applications.

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Properties of Journal Bearing Materials That Determine Their Wear Resistance on the Example of Aluminum-Based Alloys

Materials ◽

10.3390/ma14030535 ◽

2021 ◽

Vol 14 (3) ◽

pp. 535

Author(s):

Alexander Mironov ◽

Iosif Gershman ◽

Eugeniy Gershman ◽

Pavel Podrabinnik ◽

Ekaterina Kuznetsova ◽

...

Keyword(s):

Mechanical Properties ◽

Wear Resistance ◽

Journal Bearing ◽

Tribological Behavior ◽

Secondary Structures ◽

Magnesium Content ◽

Wear Rates ◽

Relative Extension ◽

Bearing Materials ◽

Antifriction Alloys

Potential relations of tribological characteristics of aluminum antifriction alloys with their compositions and mechanical properties were investigated. In this regard, the properties of eight aluminum alloys containing tin from 5.4% to 11% doped with lead, copper, silicon, zinc, magnesium, and titanium were studied. Mechanical properties such as hardness, strength, relative extension, and impact strength were analyzed. Within the tribological tests seizure load and wear of material were evaluated and secondary structures were studied afterwards. The absence of a definitive correlation between tribological behavior and mechanical properties was shown. It was determined that doping tin over 6% is excessive. The seizure load of the alloys increases with the magnesium content. Secondary structures of the alloys with higher wear rates contain one order less magnesium and tin.

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Numerical investigation of dynamic and hydrodynamic characteristics of the pad in the fluid pivot journal bearing

Proceedings of the Institution of Mechanical Engineers Part J Journal of Engineering Tribology ◽

10.1177/13506501211033045 ◽

2021 ◽

pp. 135065012110330

Author(s):

Tuyen Vu Nguyen ◽

Weiguang Li

Keyword(s):

Computational Models ◽

Journal Bearing ◽

Squeeze Film ◽

Hydrodynamic Characteristics ◽

Hydrodynamic Properties ◽

Squeeze Film Damper ◽

Lubricant Oil ◽

Oil Flow ◽

Flow Through ◽

Bearing System

The dynamic and hydrodynamic properties of the pad in the fluid pivot journal bearing are investigated in this paper. Preload coefficients, recess area, and size gap, which were selected as input parameters to investigate, are important parameters of fluid pivot journal bearing. The pad’s pendulum angle, lubricant oil flow through the gap, and recess pressure which characterizes the squeeze film damper were investigated with different preload coefficients, recess area, and gap sizes. The computational models were established and numerical methods were used to determine the equilibrium position of the shaft-bearing system. Since then, the pendulum angle of the pad, liquid flow, and recess pressure were determined by different eccentricities.

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Analysis of Morton Effect Induced Vibration based on Transfer Function Model: Influence of L/D ratio of Journal Bearing and Rotational speed

Journal of Physics Conference Series ◽

10.1088/1742-6596/1909/1/012079 ◽

2021 ◽

Vol 1909 (1) ◽

pp. 012079

Author(s):

Takafumi Suzuki ◽

Jotaro Chiba ◽

Shota Yabui ◽

Shigeyuki Tomimatsu ◽

Tsuyoshi Inoue

Keyword(s):

Transfer Function ◽

Rotational Speed ◽

Journal Bearing ◽

Transfer Function Model ◽

Function Model ◽

Morton Effect

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