Effect of Nanoparticle Additives on Journal Bearing Lubricated with Non-Newtonian Carreau Fluid

2015 ◽  
Vol 751 ◽  
pp. 137-142 ◽  
Author(s):  
W. Gunnuang ◽  
C. Aiumpornsin ◽  
Mongkol Mongkolwongrojn
Keyword(s):  
Carrying Capacity ◽  
Reynolds Equation ◽  
Energy Equation ◽  
Journal Bearing ◽  
Research Work ◽  
Load Carrying Capacity ◽  
Static Characteristics ◽  
Carreau Fluid ◽  
Load Carrying ◽  
Nanoparticle Additives

This research work presents the influence of Al2O3 nanoparticle additives on the performance characteristics of a journal bearing. Non-Newtonian fluid based on Carreau viscosity model was represented for SAE10W50 oil blended with Al2O3 nanoparticles in this work. Reynolds equation and energy equation have been formulated and solved numerically using finite difference method and multigrid multilevel techniques with boundary conditions. The static characteristics of the journal bearing under isothermal and adiabatic conditions were examined. The results show that the addition of Al2O3 nanoparticles improve load-carrying capacity of the journal but almost no change on film temperature due to good thermal property of Al2O3 nanoparticles.

Steady-state performance of a circular journal bearing lubricated with a non-Newtonian fluid considering the elastic deformation of the liner

2019 ◽  
Vol 233 (9) ◽  
pp. 1389-1396
Author(s):  
Boualem Chetti ◽  
Hamid Zouggar
Keyword(s):  
Friction Coefficient ◽  
Elastic Deformation ◽  
Power Law ◽  
Carrying Capacity ◽  
Reynolds Equation ◽  
Journal Bearing ◽  
Load Carrying Capacity ◽  
Static Characteristics ◽  
Load Carrying ◽  
Power Law Index

In this work, a numerical study of the effect of elastic deformation on the static characteristics of a circular journal bearing operating with non-Newtonian fluids obeying to the power law model is presented. The modified Reynolds equation has been derived taking into consideration the effect of non-Newtonian behavior of the fluids. To obtain the pressure distribution, the Reynolds equation has been solved using finite difference technique with appropriate iterative technique incorporating Reynolds boundary conditions. The static performance characteristics for finite-width journal bearing in terms of the load-carrying capacity, the attitude angle, friction coefficient, and the side leakage have been studied for various values of the non-Newtonian power law index n and the elastic coefficient. The results show that the increase of the power law index produces a higher load-carrying capacity, a higher side leakage, a lower attitude angle, and a lower friction coefficient. From this study, it can be concluded that the elastic deformation has an important influence on the static characteristics of the journal bearing lubricated with a non-Newtonian fluid, and this influence is more significant for the journal bearing operating at larger values of the eccentricity ratio.

Static characteristics of misaligned multiple axial groove water-lubricated bearing in the turbulent regime

2016 ◽  
Vol 231 (3) ◽  
pp. 385-398 ◽  
Author(s):  
Ravindra Mallya ◽  
Satish B Shenoy ◽  
Raghuvir Pai
Keyword(s):  
Reynolds Number ◽  
Friction Coefficient ◽  
Carrying Capacity ◽  
Journal Bearing ◽  
Load Capacity ◽  
Turbulent Regime ◽  
Load Carrying Capacity ◽  
Static Characteristics ◽  
Load Carrying ◽  
Turbulence Effects

The static characteristics of misaligned three-axial water-lubricated journal bearing in the turbulent regime are analyzed for groove angles 36° and 18°. Ng and Pan’s turbulence model is applied to study the turbulence effects in the journal bearing. The static parameters such as load-carrying capacity, friction coefficient, and side leakage are found for different degree of misalignment (DM). The change in flow regime of the lubricant from laminar to turbulent and the increase in misalignment, improved the load capacity of the bearing. For lightly loaded bearings, the friction coefficient of the bearing increased with the increase in Reynolds number.

Theoretical Analysis of Externally Pressurized Air Journal Bearing

1970 ◽  
Vol 12 (2) ◽  
pp. 123-129 ◽  
Author(s):  
B. C. Majumdar
Keyword(s):  
Experimental Data ◽  
Carrying Capacity ◽  
Reynolds Equation ◽  
Journal Bearing ◽  
Design Parameters ◽  
Load Carrying Capacity ◽  
Load Carrying ◽  
Dimensional Parameters ◽  
Bearing Design

A theoretical investigation is made to predict the performance of an externally pressurized air journal bearing having several pressure sources. The pressure distribution, which leads to the determination of load-carrying capacity and flow requirement, is obtained by solving Reynolds equation numerically. The load and flow, expressed in non-dimensional parameters, are presented for different bearing design parameters (dimensionless). The results predicted by this method are compared with others' experimental data.

Elastic Deformation Effects on the Thermo-Hydrodynamic Aspect of Porous Journal Bearings

2014 ◽  
Vol 353 ◽  
pp. 275-279
Author(s):  
S. Boubendir ◽  
Salah Larbi ◽  
R. Bennacer
Keyword(s):  
Elastic Deformation ◽  
Carrying Capacity ◽  
Reynolds Equation ◽  
Maximum Pressure ◽  
Load Carrying Capacity ◽  
Static Characteristics ◽  
Governing Equations ◽  
Load Carrying ◽  
Variation Parameter ◽  
Viscosity Variation

In this paper, the effects of porous bush elastic deformation on the static characteristics of finite porous journal bearing are investigated using Darcy’s law. The modified Reynolds equation applied to thermo-hydrodynamic problems is modified by considering the viscosity variation along the film thickness. The film pressure distribution and other characteristics such as the load carrying capacity and attitude angle are obtained by solving the governing equations numerically. Obtained results showed that deformation is considerable in the maximum pressure zone, and the elastic deformation will decrease the load carrying capacity. The viscosity variation parameter tends also to decrease the load carrying capacity.

scholarly journals Theoretical investigation of porous hydrostatic journal bearing under micropolar fluid lubrication

2020 ◽  
Vol 234 (1-2) ◽  
pp. 11-18
Author(s):  
Biplab Bhattacharjee ◽  
Prasun Chakraborti ◽  
Kishan Choudhuri
Keyword(s):  
Carrying Capacity ◽  
Micropolar Fluid ◽  
Reynolds Equation ◽  
Journal Bearing ◽  
Low Flow ◽  
Load Carrying Capacity ◽  
Static Stiffness ◽  
Design Charts ◽  
Hydrostatic Bearings ◽  
Load Carrying

The features of micropolar fluid (a non-Newtonian fluid)–lubricated short single-layered porous hydrostatic journal bearing are analyzed theoretically by an iterative method. To investigate hydrostatic journal bearing characteristics, a modified Reynolds equation in the case of micropolar fluid is derived and solved numerically. The obtained results in this work are validated by comparing the same with previously published results with Newtonian and non-Newtonian lubricants in the form of design charts. The static stiffness and load-carrying capacity of the investigated bearing are 80% and 75% higher than conventional hydrostatic bearings. The porous hydrostatic journal bearing exhibits more economical performance as it requires 40% low flow rate and low pump power, and it generates 50% less heat in contrast with other hydrostatic bearings.

Elastohydrodynamic Analysis of an Offset Journal Bearing Lubricated with Couple Stress Fluid

2010 ◽  
Vol 2 ◽  
pp. 53-62
Author(s):  
B. Chetti
Keyword(s):  
Elastic Deformation ◽  
Couple Stress ◽  
Reynolds Equation ◽  
Journal Bearing ◽  
Journal Bearings ◽  
Load Carrying Capacity ◽  
Static Characteristics ◽  
Large Molecules ◽  
Couple Stresses ◽  
Load Carrying

This work is an investigation of the performance characteristics of an offset journal bearing lubricated with a fluid with couple stresses taking into consideration the elastic deformation of the liner. The couple stresses might be expected to appear in noticeable magnitudes in liquids containing additives with large molecules. The modified Reynolds equation has been solved using the finite difference method. Load carrying capacity, attitude angle, side leakage and friction coefficients are determined for various values of couple stress parameter of a rigid and deformable bearing. It is found that, the static characteristics of journal bearings lubricated with couple stress fluids are improved compared to journal bearings lubricated with Newtonian fluids. It is concluded that, the elastic deformation of the bearing has significant influence on the bearing characteristics.

Preload effects on the static characteristics of three-lobe journal bearings lubricated with a couple stress fluid

2019 ◽  
Vol 71 (10) ◽  
pp. 1136-1143 ◽  
Author(s):  
Boualem Chetti ◽  
Wael Ahmed Crosby
Keyword(s):  
Friction Coefficient ◽  
Carrying Capacity ◽  
Couple Stress ◽  
Journal Bearing ◽  
Significant Rise ◽  
Couple Stress Fluid ◽  
Load Carrying Capacity ◽  
Static Characteristics ◽  
Content Type ◽  
Load Carrying

Purpose The purpose of this paper is to present the effect of the preload on the static characteristics of three-lobe bearings lubricated with a fluid blended with high polymer additives modeled as a couple stress fluid. Design/methodology/approach Based on the micro-continuum theory, the modified Reynolds equation for couple stress fluids is solved using a finite difference method to obtain the distribution of the pressure, the load-carrying capacity, the attitude angle, the friction coefficient and the side leakage for various values of the couple stress parameter and the preload factor. Findings The results show that the presence of a couple stress in the lubricants improves the static characteristics of this type of bearing compared to those lubricated with Newtonian fluids for any value of the preload factor. Thus, it is found that the preload significantly affects the performance of the three-lobe journal bearing lubricated with a couple stress fluid or a Newtonian fluid. Moreover, the investigation showed that increasing the preload factor exhibits an increase in the load carrying capacity and the attitude angle, but it decreases the friction coefficient and the side leakage especially at a lower preload factor. Furthermore, using a couple stress fluid and a higher preload factor led to a significant rise in the load carrying capacity and a significant reduction in the friction coefficient. Practical implications This study helped improve the performance characteristics of the three-lobe journal bearing. Originality/value The presence of couple stress in the lubricants improves the static characteristics of this type of bearing compared to those lubricated with Newtonian fluids for any value of the preload factor. The usage of the couple stress fluid and the higher preload factor led to a significant rise in the load carrying capacity and a significant reduction in the friction coefficient.

scholarly journals Effect of Viscosity Variation on the Micropolar Fluid Squeeze Film Lubrication of a Short Journal Bearing

2013 ◽  
Vol 2013 ◽  
pp. 1-7 ◽  
Author(s):  
N. B. Naduvinamani ◽  
Archana K. Kadadi
Keyword(s):  
Carrying Capacity ◽  
Micropolar Fluid ◽  
Reynolds Equation ◽  
Journal Bearing ◽  
Closed Form Solution ◽  
Squeeze Film ◽  
Load Carrying Capacity ◽  
Load Carrying ◽  
Viscosity Variation ◽  
Modified Reynolds Equation

A theoretical study of the effect of the viscosity variation on the squeeze film performance of a short journal bearing operating with micropolar fluid is presented. The modified Reynolds equation accounting for the viscosity variation in micropolar fluid is mathematically derived. To obtain a closed form solution, the short bearing approximation under constant load is considered. The modified Reynolds equation is solved for the fluid film pressure and then the bearing characteristics, such as obtaining the load carrying capacity and the squeeze film time. According to the results evaluated, the micropolar fluid as a lubricant improves the squeeze film characteristics and results in a longer bearing life, whereas the viscosity variation factor decreases the load carrying capacity and squeezes film time. The result is compared with the corresponding Newtonian case.

Study on Lubrication Simulation and Capability of Three-Lobe Journal Bearing

2014 ◽  
Vol 709 ◽  
pp. 210-214
Author(s):  
Kun Qian ◽  
Wei Gang Guo
Keyword(s):  
Carrying Capacity ◽  
Reynolds Equation ◽  
Journal Bearing ◽  
Rotation Speed ◽  
Load Carrying Capacity ◽  
Load Carrying ◽  
Bearing Load ◽  
The Stability ◽  
Eccentric Distance

The lubrication state of three-lobe bearing is simulated by using Reynolds equation. It concluded that the load-carrying capability of three-lobe bearing increases with the eccentric distance between the centers of axis and bearing with a nonlinear way. The largest bearing load-carrying capacity occurs in the eccentric direction of 30 °and making sure the eccentric direction can improve the stability of the system. To improve the rotation speed of the axis is beneficial to promote the load-carrying capacity.

scholarly journals Comparative study of spherical dimple and bump effects on the tribological performances of journal bearing

2018 ◽  
Vol 233 (1) ◽  
pp. 139-157 ◽  
Author(s):  
Chao Gui ◽  
Fanming Meng
Keyword(s):  
Friction Force ◽  
Carrying Capacity ◽  
Reynolds Equation ◽  
Journal Bearing ◽  
Hydrodynamic Pressure ◽  
Load Carrying Capacity ◽  
Transform Method ◽  
Cavitation Effect ◽  
Fast Fourier Transform Method ◽  
Load Carrying

In the present study, tribological performances of journal bearings with the representative spherical dimples and bumps are compared numerically. In doing so, the hydrodynamic pressure of the lubricant is solved by the Reynolds equation considering the lubricant cavitation effect. Meanwhile, the elastic deformation is calculated by the continuous convolution fast Fourier transform method. The enhanced load-carrying capacity and the reduced friction force occur only when the dimples are located at pressure rising part of the bearing. The bumps located at the pressure falling part can enhance the load-carrying capacity but increase the friction force. The above dimple and bump effects change at the varied feature sizes and intervals.

Sign in / Sign up

Export Citation Format

Share Document