| 
					h0: A high axial bearing stiffness, 
					self-aligning capability and the minimal flow is obtained 
					with small film thickness. The minimal value of the film 
					thickness is limited by bearing deflections and flatness of the 
					bearing surface and is usually related to the bearing size. 
					δ, h2: The volume of the pocket must be as 
					small as possible to make the bearing less sensitive to 
					instability. The pocket however is needed to get a smooth 
					pressure distribution in the circumference and secondly to 
					realize simple orifice compensation. The pressure 
					distribution in the groove is assumed to be homogenous which 
					is a good approximation for a large groove depth. Numerical 
					calculations are required to calculate the effect of the 
					pressure drop in shallow grooves. Ac: 
					The restrictor can become inherent with shallow grooves and 
					Ac must therefore be checked. The pressure drop over passage 
					A1 of the simple orifice restrictor is more than four times 
					higher than that over the annulus area A2 when Ac>1 (Fig 
					12.2 of the book). |