Evaluation of hydrodynamic lubrication performance of textured surface from the perspective of skewness and kurtosis

2018 ◽  
Vol 70 (5) ◽  
pp. 829-837 ◽  
Author(s):  
Xia He ◽  
Wenling Liao ◽  
Guorong Wang ◽  
Lin Zhong ◽  
Mengyuan Li
Keyword(s):  
Cross Section ◽  
Reynolds Equation ◽  
Hydrodynamic Lubrication ◽  
Numerical Approach ◽  
Textured Surface ◽  
Content Type ◽  
Lubrication Performance ◽  
Texture Type ◽  
Negative Skewness ◽  
Skewness And Kurtosis

Purpose The purpose of this study is to investigate the influence of texture on hydrodynamic lubrication performance of slide surface from the perspective of skewness and kurtosis. Design/methodology/approach Hydrodynamic lubrication theoretical model of textured surface was established based on two-dimensional Reynolds equation, and finite difference algorithm was used as the numerical approach in the paper. Skewness and kurtosis of surface were obtained by discrete calculation. Findings Numerical analysis results show that the influence law of texture types on skewness, kurtosis and hydrodynamic lubrication was the more negative skewness and higher kurtosis, the better hydrodynamic lubrication performance when texture cross section contour and geometric parameters were the same. Similarly, the same influence law of skewness, kurtosis and hydrodynamic lubrication performance by texture cross-section contour was observed. However, it was unable to evaluate the effect of texture angle on hydrodynamic lubrication performance of textured surface from the perspective of skewness and kurtosis. Originality/value This paper confirms the feasibility of evaluating influence of texture types and texture cross-section contour on hydrodynamic lubrication performance from the perspective of skewness and kurtosis and provides a way to optimize texture type and texture cross section.

Effectiveness of multi-shape laser surface texturing in the reduction of friction under lubrication regime

2016 ◽  
Vol 68 (1) ◽  
pp. 116-124 ◽  
Author(s):  
Dawit Zenebe Segu ◽  
Pyung Hwang
Keyword(s):  
Hydrodynamic Lubrication ◽  
Surface Texturing ◽  
Laser Surface ◽  
Laser Surface Texturing ◽  
Textured Surface ◽  
Content Type ◽  
Laser Ablation Process ◽  
Specific Formula ◽  
Steel Surfaces ◽  
Lubrication Conditions

Purpose – The purpose of this paper is to investigate and discuss the effect of multi-shape laser surface texturing (LST) steel surfaces on tribological performance. Design/methodology/approach – The textured surface with some specific formula arrays was fabricated by laser ablation process by combining patterns of circles and triangles, circles and squares and circles and ellipses. The tribological test was performed by a flat-on-flat tribometer under dry and lubrication conditions, and results were compared with that of untextured surface. Findings – The results showed that the textured surface had better friction coefficient performance than the untextured surface due to hydrodynamic lubrication effect. Through an increase in sliding speed, the beneficial effect of LST performance was achieved under dry and lubrication conditions. Originality/value – This paper develops multi-shape LST steel surfaces for improving the friction and wear performance under dry and lubrication conditions.

Effect of laser-textured micro dimples on inhibition of stick-slip phenomenon of sliding guideway

2022 ◽  
Vol ahead-of-print (ahead-of-print) ◽  
Author(s):  
Yonghong Fu ◽  
Jie Yang ◽  
Hao Wang ◽  
Yuyang He
Keyword(s):  
Hydrodynamic Lubrication ◽  
Textured Surface ◽  
Stick Slip ◽  
Content Type ◽  
Speed Range ◽  
Lubrication Condition ◽  
Micro Dimples ◽  
Pin On Disk ◽  
Micro Dimple ◽  
Slip Phenomenon

Purpose This study aims to investigate the efficacy of micro dimple in inhibiting stick-slip phenomenon on the sliding guideway. Design/methodology/approach In this study, micro-dimples were fabricated by laser on surfaces of steel disk and guideway. The disks and guideways were respectively performed pin-on-disk tribological tests and working condition experiments to study differences in lubrication condition and friction stability between textured and untextured surfaces. Findings Micro-dimples help reduce critical sliding speed that allows contact surfaces to enter in hydrodynamic lubrication regime. This increases hydrodynamic lubrication range and narrows speed range where stick-slip phenomenon can occur, enhancing sliding guideway’s adaptability for broader working conditions. Furthermore, friction stability on the textured surface improved, lowering the occurrence possibility of stick-slip phenomenon. Finally, difference between static and kinetic frictions on the textured surface is lower relative to the untextured surface, which decreases the critical velocity when the stick-slip phenomenon occurs. Originality/value The results indicate that laser-textured micro-dimples are significantly conducive to inhibit stick-slip phenomenon, thus providing smoother movement for the guideway and eventually increasing precision of the machine.

Numerical simulation of lubrication performance on chevron textured surface under hydrodynamic lubrication

2021 ◽  
Vol 154 ◽  
pp. 106704
Author(s):  
Zihan Shen ◽  
Fengchao Wang ◽  
Zhiguo Chen ◽  
Xiaopeng Ruan ◽  
Hanghang Zeng ◽  
...  
Keyword(s):  
Numerical Simulation ◽  
Hydrodynamic Lubrication ◽  
Textured Surface ◽  
Lubrication Performance

Effect of piston clearance on the lubrication performance in axial piston pump

2019 ◽  
Vol 72 (1) ◽  
pp. 146-150
Author(s):  
Bora Lee ◽  
Yonghun Yu ◽  
Yong-Joo Cho
Keyword(s):  
Reynolds Equation ◽  
Design Method ◽  
Contact Region ◽  
Content Type ◽  
Piston Cylinder ◽  
Leakage Flow Rate ◽  
Lubrication Performance ◽  
Secondary Motion ◽  
Lubrication Characteristics ◽  
Axial Piston

Purpose This paper aims to provide a reliable and efficient numerical piston–cylinder design method and assess the effect of clearance on the piston-cylinder lubrication. Design/methodology/approach Numerical analyses of lubrication characteristics were performed for the piston–cylinder interface. The axial piston was numerically modeled, and the film pressure was calculated using the unsteady two-dimensional Reynolds equation. The behavior of the piston was analyzed by calculating the eccentricity satisfying the force and moment balance. Findings The secondary motion of the piston included numerically simulated several cycles until the piston behavior converged, and contact with the inner wall of the cylinder and friction region was estimated. Results showed that the piston–cylinder clearance affected the contact force, length of the contact region and leakage flow rate. Originality/value This result improves the understanding of the piston–cylinder lubrication and suggests considerations in terms of lubrication in clearance design.

Behaviour of two-lobe hole-entry hybrid journal bearing system under the combined influence of textured surface and micropolar lubricant

2017 ◽  
Vol 69 (6) ◽  
pp. 844-862 ◽  
Author(s):  
Chandra B. Khatri ◽  
Satish C. Sharma
Keyword(s):  
Design Methodology ◽  
Reynolds Equation ◽  
Journal Bearing ◽  
Numerical Technique ◽  
Surface Texturing ◽  
Textured Surface ◽  
Performance Parameters ◽  
Content Type ◽  
Fluid Theory ◽  
Bearing System

Purpose The aim of the present paper is to study the combined influence of textured surface and micropolar lubricant behaviour on the performance of two-lobe hole-entry hybrid journal bearing system. The bearing performance parameters of the textured circular/two-lobe hole-entry hybrid journal bearing system have been computed against the constant vertical external load supported by the bearing. Design/methodology/approach In this work, Eringen’s micropolar fluid theory has been used to derive the governing Reynolds equation. The consequent solution of the governing Reynolds equation has been obtained by using finite element method (FEM) numerical technique. Findings The present study indicates that the use of the textured surface, two-lobe profile of bearing and micropolar lubricant, significantly enhances the bearing performance as compared to non-textured circular journal bearing. Originality/value The present study concerning the influence of surface texturing on the behaviour of the two-lobe hole-entry hybrid journal bearing lubricated with micropolar lubricant is original. The theoretically simulated results of the present study will be useful to design an efficient journal bearing system.

Optimization of hydrodynamic lubrication performance based on a heterogeneous slip/no-slip surface

2019 ◽  
Vol 71 (6) ◽  
pp. 772-778
Author(s):  
Zhenpeng Wu ◽  
Xianzhong Ding ◽  
Liangcai Zeng ◽  
Xiaolan Chen ◽  
Kuisheng Chen
Keyword(s):  
Friction Coefficient ◽  
Liquid Film ◽  
Bearing Capacity ◽  
Slip Surface ◽  
Hydrodynamic Lubrication ◽  
Slip Zone ◽  
Content Type ◽  
Starting Point ◽  
Lubrication Performance ◽  
Residual Space

Purpose This paper aims to use the method of curve splicing to combine the slip zone and the no-slip zone to further improve the lubrication performance of the liquid film. The combination of the slip zone and the no-slip zone of an existing heterogeneous surface is still a single line stitching method so that a very large residual space at the surface of the friction pairs remains present, necessitating further improvement of the joining scheme between the slip zone and the no-slip zone in heterogeneous surfaces. Design/methodology/approach A set of discrete sinusoids is used as the splicing track for both the slip zone and the no-slip zone, the starting point and amplitude of the curve are introduced as the simulation variables and the effects of these variables on the bearing capacity and friction coefficient of the liquid film are comprehensively analyzed. Findings The results show that the method of selecting the sinusoidal curve as the slip zone and the no-slip zone trajectory, which is based on the existing method of linear stitching, can further enhance the bearing capacity and reduce the friction coefficient of the liquid film. Originality/value This method can further enhance the bearing capacity and reduce the friction coefficient of the liquid film.

Effect of percolation on hydrodynamic lubrication of rough bilayer porous bearing with circular contact

2019 ◽  
Vol 72 (1) ◽  
pp. 109-115
Author(s):  
Guotao Zhang ◽  
Baohong Tong ◽  
Shubao Yang ◽  
Liping Shi ◽  
Yanguo Yin
Keyword(s):  
Hydrodynamic Lubrication ◽  
Structural Parameters ◽  
Single Layer ◽  
Polar Coordinates ◽  
Root Mean Square Roughness ◽  
High Porosity ◽  
Content Type ◽  
Porous Bearing ◽  
Lubrication Performance ◽  
Filtering Technique

Purpose The purpose of this paper was to study the hydrodynamic lubrication of rough bilayer porous bearing to reveal the effect of percolation. Design/methodology/approach The seepage lubrication model of the circular bilayer porous bearing was established in polar coordinates. The digital filtering technique and Darcy’s law were used to simulate the rough surface and the percolation characteristic of the oil bearing, respectively. The influence of the structural parameters on the lubrication performance was analyzed. Findings Compared with the ordinary monolayer oil bearing with high porosity, the bilayer bearing can reduce the whole porosity, prevent oil infiltrating into the porous medium and have better lubrication performance. The lubrication performance of bilayer oil bearing is better than that of the single-layer oil bearing which has a higher porosity. With increasing root-mean-square roughness or decreasing surface porosity, the lubrication performance of the bilayer bearing improves. The lower the porosity of the surface layer, the better the lubrication performance. Originality/value This research provides a theoretical basis for clarifying the lubrication mechanism and influence the mechanism of the bilayer oil bearing.

Sign in / Sign up

Export Citation Format

Share Document