Research on Static and Dynamic Characteristics of Gas-lubricated Microbearings for Microfluidic Devices

Abstract

Aerodynamic journal microbearings with microtribological phenomena significantly influence the operating stability of microfluidic devices. The modified Reynolds equations including different rarefaction models are derived and are solved by the partial derivative method and relaxation iteration algorithm. The effects of Knudsen number and bearing parameters on the static and dynamic characteristics of microbearings are investigated in detail. The results show that the rarefaction effect plays a crucial role in the ultra-thin gas film lubrication. The maximum film pressure of Fukui–Kaneko (FK) model is lowest and the result in Boltzmann model is largest in small Knudsen number regions. As the Knudsen number increases further, the curve of FK model is coincident with that of the Boltzmann model in the transition regime. The direct stiffness coefficients of Boltzmann model increase with the increase of eccentricity ratio and aspect ratio, whereas the effect of Knudsen number on the damping coefficients yields a relatively complicated trend.

Influence of Temperature Effect on the Static and Dynamic Performance of Gas-Lubricated Microbearings

“…Due to its lower calculation cost and higher precision, the FK model had been applied in various cases. In recent years, by using the FK model, some scholars [16,17] have found that the rarefaction effect has a large influence on the load capacity and attitude angle of MEMS bearing compared with those in the continuous model.…”

Review of Wind Power Bearing Wear Analysis and Intelligent Lubrication Method Research

“…Due to the wind power bearings mainly work in the plateau, grassland air thinning, and other areas, studying the gas lubrication micro-bearing microfluidic control device can provide a reliable research basis for wind power bearings. WU et al [194] modeled the journal micro-bearing (Figure 14), derived the modified Reynolds equation for the sparse model under different conditions, and carried out a detailed study on the parameters of the micro-bearing and the Knudsen number to conclude that when the Knudsen number is less than 0.325, the sparse gas can form a thin lubrication film on the surface of the non-stop-running journal micro-bearing, which can reduce the friction coefficient and bear the bearing load significantly. Due to the wind power bearings mainly work in the plateau, grassland air thinning, and other areas, studying the gas lubrication micro-bearing microfluidic control device can provide a reliable research basis for wind power bearings.…”

“…Bearing gas lubrication structure diagram and three-dimensional view. (a) Schematic view; (b) 3D graphical representation[194].…”