Scholarly record

THE EXPERIMENTAL BASE FOR DETERMINING THE FORM OF THE AEROSTATIC BEARINGS SEALING GROOVE

Михаил Дербин

Abstract

References to theoretical research of aerostatic bearings and the method of their analysis for choosing options of aerostatic direction are provided. The calculation is done by means of a numerical method based on the field pressure approximation in a gap by means of differential algebraic equations, which takes into account two-dimensionality of the lubrication flow in bearings of various configuration and gives results close to actual ones. With the assumptions made in order to simplify calculations, flow line deviations from the direction perpendicular to fine grooves, when the gap is increasing and when the fine groove cross-section is decreasing, are not taken into consideration, as well as inertial forces in the lubrication flow and the air motion in the groove is taken to be laminar. The scheme of aerostatic bearings with the set parameters, which are the width and the length, is shown. The bearing section includes a closed rectangular fine groove, in the middle part of the lateral sides of which there are ventilation holes. The isolated aerostatic bearing is gridded with the spacing. A special mathematical software for calculating aerostatic bearings was applied to develop a program. In experimental studies in order to evaluate the impact of the sealing grooves on the carrying capacity of aerostatic bearings an aerostatic bearing with certain parameters was taken. The scheme of the working surface of the aerostatic bearings with sealing groove and the layout of aerostatic bearings test bed are shown. The air system of the experimental setup includes a compressor, air manifold consisting of rubber pressure hoses; demister for evacuating mechanical impurities and humidity; needle air valve for air pressure adjustment built in the area variable flow-meter and gas pressure gauge. For experimental studies the electronic variable area flow meter, which has a number of advantages compared to the flow meter with a glass tube, was used. The device description and principle of the flat aerostatic bearings test bed function is shown. In the course of the experimental research grooves of 4 different profiles have been studied. The results of the experimental research have shown different plate lift heights for grooves of different profiles. The research results were taken to draw a conclusion: with all conditions being equal, the maximum plate lift height is reached by an aerostatic bearing of a teardrop profile, which corresponds to the maximum lifting capacity of the aerostatic bearing.

Publication details

Back to publication list