| The SailRail system is a compliant, air-lubricated linear thrust bearing, which is capable of achieved coefficients of sliding friction as low as 0.2%. Development of this system has been done on a trial-and-error basis over the last 30 years; the present work is aimed at understanding the theory of operation of the bearing. Two avenues are explored: a simplified-geometry model of the bearing is designed and used to study the effects of material properties on air-bearing action. Also, a representative configuration is used to investigate nozzle geometry on effective friction. Results show the current compliant material, cellulose tissue, exhibits better performance than cast urethane or sheet polyethylene; in addition, tissue exhibits excellent moment-recovery properties. A new radial nozzle geometry, simpler than the currently-used one, is shown to not have an adverse effect on performance; in some cases, performance is enhanced. |
