TourTourAerostatic thrust bearing with porous restrictor
 Diameter bearing 2R0   10-3 m
 Diameter restrictor 2R1   10-3 m
 Fly height h0   10-6 m
 Supply pressure pS   106 Pa
 Ambient pressure pA   106 Pa
 Pressure factor β  
 Permeability kp   10-15 m2
 Restrictor pressure pR  
 Load capacity F*  
 Effective bearing area Ae/A  
 Flow rate M   10-6 kg/s
 Thickness porous cylinder s   10-3 m
 Load capacity F   N
 Axial stiffness S=-dF/dh   10 6 N/m
 Flow rate Q   l/min

2R1: The size of the pocket must be as small as possible to make the bearing less sensitive to instability. The minimal value of R1 is limited by Ac.

h0: A high axial bearing stiffness, self-aligning capability and the minimal flow is obtained with small fly height. The minimal value of the fly height gap is limited by bearing deflections and flatness of the bearing surface and is usually related to the bearing size.

Permeability: This material constant determines the thickness of the porous surface required to get the right pressure drop from pS to pR. The permeability can be reduced by impregnating the porous material.