Effect of gas slip on the behavior of the aerostatic guideway

Abstract

Purpose This paper aims to better understand the dynamic characteristics of an aerostatic slider caused by a gas film, and the impact of a gas film slip on the load capacity, stiffness and dynamic stiffness of the guideway is studied. Design/methodology/approach In theory, the Navier velocity slip model is introduced for fluid continuous flow equation to calculate the flow state in the micro-state; in experimental techniques, the stiffness experiment of the guideway by digital inductance meter is performed under different loadings, which are used to inspect the simulation results. Findings The maximum value of bearing stiffness in the condition of considering that the gas slip is larger than that of not considering the gas slip, and the gas film clearance of maximum bearing stiffness in the condition of considering the gas slip is less than that of not considering the gas slip. This is verified by the measurement of the stiffness of the guideway. Originality/value This paper mostly studies the influence of the gas slip effects on the performance of the aerostatic guideway, which will make a certain contribution to the guideway stability and the machining precision of the machine tool.

Research Developments of Aerostatic Thrust Bearings: A Review

“…Chen, D. J. introduced the Navier velocity slip model to improve the theoretical model of the aerostatic guideways. It was found that the first-order velocity slip model was more suitable to predict the performance of aerostatic guideways [21,22]. All the above results show that it is necessary to consider the velocity slip effect in the design of ATBs.…”

Theoretical and Experimental Investigation on Air Film Pressure Field Characteristics of Aerostatic Thrust Bearing

“…Since the air film model contains squirt flow and shear flow, and the Reynolds number Re is small, based on the Wilcox k-ω model, 28 the specific dissipation rate ω is introduced to establish a standard k-ω model. The turbulent kinetic energy k and ω are obtained from the following transport equation ( 5) and (6).…”

“…How to improve their performance has become the focus of many scholars at home and abroad. 3 Chen et al [4][5][6][7][8] studied the coupling effects of velocity slip, rarefaction effect and effective viscosity of the air film on the performance of aerostatic guideway in micro-scale, compared the load capacity and stiffness under different working conditions. Chen et al 9,10 studied the effect of backflow phenomenon and geometric parameters of rectangular grooves on the static performance of aerostatic bearing and made recommendations for bearing design.…”

Electric-Magnetic-Mechanical Coupling in Precision Machines

“…The design and manufacture of highprecision aerostatic guideway made of glass material (Lai et al 2019), metal material (Chen et al 2018a), marble material (Yao et al 2016) can achieve the guideway precision with linearity better than 0.1 μ m through the coupling of linear motor and different types of guideways. In addition to the guide rail material, the guide rail media affects the linear accuracy and rigidity, such as gas (Chen et al 2017), liquid (Liu et al 2019), and other factors, among which the aerostatic guide rail has high accuracy and rigidity and the relative aerostatic guide rail has low accuracy and high rigidity. In the precision machining equipment and process design, the machining object and material removal rate are the main parameters to be considered, as well as the electromagnetic characteristics of the motor itself (Gannel 2019).…”