Analysis of the coated and textured ring/liner conjunction based on a thermal mixed lubrication model

Abstract

For the ring/liner conjunction, well-designed surface texturing has been regarded as a potential means to improve its tribological performance, as well as the application of coating. However, so far most researchers focused on the one of these aspects. In this study, the combined effect of coating and texturing on the performance of ring/liner conjunction is numerically investigated. A thermal mixed lubrication model is presented. The effects of the coating's thermal and mechanical properties on the tribological performance are studied under the cold and warm engine operating conditions. Along with the increasing coating thickness, the effects of the coating's thermal properties on friction loss are found to be significant, as well as the effects of the coating's mechanical properties. It is also found that a soft coating with a lower thermal inertia has a greater ability to reduce the friction loss of the textured conjunction.

A review of recent advances in tribology

“…In order to improve the properties of coatings and accelerate the innovation of materials, Chen et al [267][268][269] investigated the coating formation mechanism from a more microscopic perspective, including the particle in-flight status and droplet spreading process. Gu et al [270] analyzed the coated and textured ring/liner conjunction based on a thermal mixed lubrication mode. High velocity oxygen-fuel (HVOF) and high velocity air-fuel (HVAF) spraying techniques were used to deposit FeVCrCbased coatings to increase wear resistance of metals, and these coatings exhibited very low sliding wear rates [271].…”

Investigation on the Frictional Performance of Surface Textured Ring-Deformed Liner Conjunction in Internal Combustion Engines

“…In these works [13][14][15][16][17], the lubrication condition of the RLC was assumed to be fully flooded, and an isothermal condition was also considered. By considering that the oil film thermal effect caused by friction and the prevalent starved lubrication condition in an RLC, Meng and his coworkers [18][19][20] studied the effects of surface texture on the frictional characteristics of an RLC. Their results showed that surface texture can reduce the friction of an RLC significantly, even if the lubrication condition was starved.…”

“…Their results showed that surface texture can reduce the friction of an RLC significantly, even if the lubrication condition was starved. In the works of Meng et al [18][19][20], an ideal circular liner was considered to evaluate the frictional characteristics of a surface textured RLC.…”

“…ε is the cavity fraction, and more discussion on the cavity fraction ε is provided in the work of Gu et al [32]. p c is the cavity pressure, and it was assumed to be zero according to the reported works [2,20,23]. φ x and φ y are the pressure flow coefficients in the x and y directions, φ s and φ c are the coefficients of shear flow and contact flow; they can be calculated by using the classic P and C (Patir and Cheng) method [33,34] and W and Z (Wu and Zheng) method [35], respectively.…”

“…φ x and φ y are the pressure flow coefficients in the x and y directions, φ s and φ c are the coefficients of shear flow and contact flow; they can be calculated by using the classic P and C (Patir and Cheng) method [33,34] and W and Z (Wu and Zheng) method [35], respectively. These methods have been widely used in the simulation of RLCs with rough surfaces because they have the advantages of low cost in computation time and easy realization [20,36]. According to the P and C method and the W and Z method, the pressure flow, shear flow, and contact flow coefficients can be written as follows:…”