Novel nano bearings constructed by physical adsorption

Abstract

The paper proposes a novel nano bearing formed by the physical adsorption of the confined fluid to the solid wall. The bearing is formed between two parallel smooth solid plane walls sliding against one another, where conventional hydrodynamic lubrication theory predicted no lubricating effect. In this bearing, the stationary solid wall is divided into two subzones which respectively have different interaction strengths with the lubricating fluid. It leads to different physical adsorption and slip properties of the lubricating fluid at the stationary solid wall respectively in these two subzones. It was found that a significant load-carrying capacity of the bearing can be generated for low lubricating film thicknesses, because of the strong physical adsorption and non-continuum effects of the lubricating film.

Relative Slip Amount Dependent on the Interfacial Shear Strength in a Nano Channel

“…It was shown that the relative slip amount is constant in the inlet zone of the channel, where the interfacial slippage occurs. This substantiates the assumption made in the analysis of this kind of channel as shown in the study by Zhang (2015). It was also shown that with the increases of the channel height or the fluidwall interfacial shear strength, the interfacial slippage is reduced.…”

“…In the study by Zhang (2015), an analysis was presented for a nano bearing formed between two parallel smooth solid planes respectively considering the fluid-wall interfaical slippage in the bearing inlet and outlet zones, by using the parameter of the relative slip amount ( s  ). In that analysis (Zhang, 2015), it was assumed that the relative slip amounts were respectively constant in the bearing inlet and outlet zones, and it was also phrased that the relative slip amount should be dependent on the fluid-wall interfacial shear strength.…”

“…In that analysis (Zhang, 2015), it was assumed that the relative slip amounts were respectively constant in the bearing inlet and outlet zones, and it was also phrased that the relative slip amount should be dependent on the fluid-wall interfacial shear strength.…”

“…One of its advantage is the convenience of the analysis, particularly when it can be assumed as constant as done in the study by Zhang (2015). This parameter is obviously related to the interfacial slipping velocity (Zhang, 2015).…”

A concentric hydrodynamic journal bearing with the boundary slippage

“…3. Plots of f w against φ tot for given ψ φ values (Zhang, 2015a) When φ tot = 2π, the dimensionless load is:…”