Closure to “Discussion of ‘Investigation of the Effects of Initial Fluid Film Profile on Pumping Ring Operation’” (1983, ASME J. Lubr. Technol., 105, p. 614)

1983 ◽  
Vol 105 (4) ◽  
pp. 614-614
Author(s):  
P. J. Smith ◽  
T. G. Keith
Keyword(s):  
Fluid Film ◽  
Film Profile

Analysis on the steady state performance of a multi pad externally adjustable fluid film bearing

2019 ◽  
Vol 71 (6) ◽  
pp. 803-809 ◽  
Author(s):  
Girish Hariharan ◽  
Raghuvir Pai
Keyword(s):  
Steady State ◽  
Reynolds Equation ◽  
Load Capacity ◽  
Fluid Film ◽  
Finite Difference Approximation ◽  
Difference Approximation ◽  
Content Type ◽  
Bearing Load ◽  
Performance Capability ◽  
Film Profile

Purpose This study aims to investigate the performance characteristics of an externally adjustable bearing with multiple pads in steady state conditions. The proposed adjustable bearing geometry can effectively control the hydrodynamic operation in bearing clearances by adjusting the pads in radial and tilt directions. These pad adjustments have a significant role in improving the bearing characteristics such as load capacity, attitude angle, side leakage, friction variable and Sommerfeld number, which will be analysed in this paper. Design/methodology/approach The adjustable bearing is designed with circumferentially spaced four bearing pads subjected to similar radial and tilt adjustments. Tilt angles are applied along the leading edges of bearing pads. A modified film thickness equation is used to incorporate the pad adjustments and accurately predict the variation in film profile. Finite difference approximation is adopted to solve the Reynolds equation and discretize the fluid film domain. Findings For negative radial and tilt adjustments, higher hydrodynamic pressures are generated in bearing clearances, which increases the bearing load capacity at different eccentricity ratios. From comparative analysis for different pad adjustments, superior bearing performance is observed for bearing pads under negative radial and negative tilt adjustments. Originality/value This research presents a detailed theoretical approach to analyse the performance capability of a four pad adjustable bearing geometry, which is not available in literatures. Improved bearing performances with negative pad adjustments can attract bearing designers to implement the proposed adjustability-bearing concept in rotating machineries.

A Study of the Elastohydrodynamic Problem in Rectangular Elastomeric Seals

1984 ◽  
Vol 106 (4) ◽  
pp. 505-512 ◽  
Author(s):  
E. Prati ◽  
A. Strozzi
Keyword(s):  
Pressure Distribution ◽  
Contact Pressure ◽  
Elastohydrodynamic Lubrication ◽  
Fluid Film ◽  
Hydrodynamic Theory ◽  
Sliding Velocity ◽  
Dry Contact ◽  
Elastomeric Seals ◽  
Film Profile

This paper deals with the study of the elastohydrodynamic lubrication in elastomeric rectangular seals with rounded edges. The photoelastic and the numerical methods are employed in the determination of the dry contact pressure distribution. The existence of two contact pressure peaks near the seal edges is clarified. The influence of the sealed pressure and the sliding velocity on the pressure distribution is examined experimentally. The influence of Poisson’s ratio and constitutive relation on the stress field is studied numerically. The inverse hydrodynamic theory and the numerical method are used in the determination of the fluid film profile. The experimental and numerical fluid film shapes at the inlet are discussed. The influence on the film shape of the sealed pressure is studied experimentally, while the influence of the sliding velocity is examined numerically. The agreement between the experimental and the numerical results for the common cases is satisfactory.

Investigation of the Effects of Initial Fluid Film Profile on Pumping Ring Operation

1983 ◽  
Vol 105 (4) ◽  
pp. 609-614
Author(s):  
P. J. Smith ◽  
T. G. Keith
Keyword(s):  
Pressure Distribution ◽  
Flow Pattern ◽  
Pronounced Effect ◽  
Fluid Film ◽  
Shaft Seal ◽  
Initial Film ◽  
Film Profile

The effect of the initial fluid film profile on the pumping capacity of a pumping ring shaft seal has been investigated numerically. Linear, concave, convex and compound film shapes were considered. It was found that initial film shape has a pronounced effect on both the amount of fluid pumped and on the character of the flow pattern and pressure distribution within the film.

Effect of the fluid film profile on the performance of magnetohydrodynamic bearings

Wear ◽  
1983 ◽  
Vol 84 (1) ◽  
pp. 15-31
Author(s):  
E.A. Salem ◽  
M.F. Khalil ◽  
S.A. Hakim
Keyword(s):  
Fluid Film ◽  
Film Profile

scholarly journals Improvement of Tilting-Pad Journal Bearing Operating Characteristics by Application of Eddy Grooves

Lubricants ◽  
2021 ◽  
Vol 9 (2) ◽  
pp. 18
Author(s):  
Eckhard Schüler ◽  
Olaf Berner
Keyword(s):  
High Speed ◽  
Journal Bearing ◽  
Load Capacity ◽  
Fluid Film ◽  
Operating Characteristics ◽  
Fluid Film Bearings ◽  
Tilting Pad ◽  
Bearing Load ◽  
Bearing Loads ◽  
Tilting Pad Journal Bearing

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.

First Paper: Effect of Under-Lip Temperature on the Lubrication of Rotary Shaft Garter Spring Seals

1966 ◽  
Vol 181 (1) ◽  
pp. 185-190 ◽  
Author(s):  
D. J. Lines ◽  
J. M. Lawrie ◽  
J. P. O'Donoghue
Keyword(s):  
Coefficient Of Friction ◽  
Operating Temperature ◽  
Lubrication Theory ◽  
Fluid Film ◽  
Hydrodynamic Parameter ◽  
Accurate Knowledge ◽  
The Coefficient Of Friction ◽  
Surface Thermocouple ◽  
Sealing Mechanism ◽  
Film Lubrication

Although rotary shaft garter spring seals are widely used throughout industry, very little is known about the sealing mechanism of the lip-shaft interface. It is now generally accepted that some sort of fluid film separates the lip and the shaft. Previous workers have also postulated a relationship between the coefficient of friction and a non-dimensional hydrodynamic parameter, as in standard lubrication theory. This present paper clarifies this relationship, and shows that seals can also operate over the mixed friction, as well as the full film lubrication region. The results were obtained by accurate knowledge of the operating temperature under the sealing lip. Two types of surface thermocouple were developed to do this and these are described in full.

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