Effect of shape/size and distribution of microgeometries of textures on tribo-performance of crankpin bearing

Abstract

The effect of the shape/size and distribution of microgeometries of textures on improving the tribo-performance of crankpin bearing is proposed. Based on a combined model of the slider-crank mechanism dynamic and hydrodynamic lubrication, the distribution density, area density, and shape of spherical textures, square-cylindrical textures, wedge-shaped textures, and a hybrid between spherical texture and square-cylindrical texture on the crankpin bearing's tribo-performance are investigated under different operating conditions of the engine. The tribological characteristic of the crankpin bearing is then evaluated via the indexes of the oil film pressure p, asperity contact force, friction force, and friction coefficient of the crankpin bearing. The research results show that the distribution density with n = 12 and m = 6, and area density with α = 30% of various microtextures have an obvious effect on ameliorating the crankpin bearings tribo-performance. Concurrently, at the mixed lubrication region, the shape of the square-cylindrical texture on improving the tribo-performance is better than the other shapes of the spherical texture, wedge-shaped texture, and spherical and square-cylindrical texture. Particularly, all the average values of the asperity contact force, friction force, and friction coefficient with a square-cylindrical texture are significantly reduced by 14.6%, 19.5%, and 34.5%, respectively, in comparison without microtextures. Therefore, the microtextures of the spherical texture applied on the bearing surface can contribute to enhance the durability and decrease the friction power loss of the engine.

Effect of the micro-textured piston on the performance of a hermetic reciprocating compressor

“…32,33 In the literature, there are many studies on computational fluid dynamics to observe the lubrication oil flow over microtextures. [34][35][36] However, the majority of the work performed with micro-texturing is experimental due to its complexity under boundary/mixed or starved conditions. An experimental study was carried out by Surya et al 37 to study the tribological benefits of various laser surface textures under realistic operating conditions of starved lubrication by measuring the friction coefficient.…”

A Comprehensive Numerical Study of a Wedge-Shaped Textured Convergent Oil Film Gap

“…The current paper focuses on a comprehensive study of such a texture on a convergent oil film gap. In [19,20], a wedge-shaped texture, among others, was examined under mixed lubrication. In contrast to van Liem et al [19], who focused on the size and distribution of textures in mixed lubrication, Maier et al [20] concentrated on the wear simulation of wedge-shaped surfaces.…”

“…In [19,20], a wedge-shaped texture, among others, was examined under mixed lubrication. In contrast to van Liem et al [19], who focused on the size and distribution of textures in mixed lubrication, Maier et al [20] concentrated on the wear simulation of wedge-shaped surfaces. In both publications, specific geometries were chosen and analyzed.…”

“…This leads to the question of the influence that the geometric parameters of a wedge-shaped texture have and which geometry will best enhance the performance. As in many technical applications, full-film lubrication is present, and this was not determined for wedge-shape textures by [19,20]. In this study, such a lubrication regime will be analyzed.…”

“…determined for wedge-shape textures by [19,20]. In this study, such a lubrication regime will be analyzed.…”