慣性気体軸受のCFD解析

（超高速回転時における軸受特性の調査）

抄録

Hydroinertia gas journal bearings have been used for ultra high-speed rotational machines such as those used in solid state nuclear magnetic resonance (NMR) devices. This type of bearing has inherent orifice restrictors and a large radial clearance compared with conventional externally pressurized gas journal bearings. The large radial clearance makes these bearings suitable for use with a rapidly rotation sample tube (shaft) since instabilities are suppressed by the reduction in hydrodynamic effects. These bearings achieve stable operation for ultra high-speed rotation of spiner shaft at several million rpm. However, solid state NMR devices require a further high speed rotation because of improvement of analysis precision. Therefore, a hydroinertia gas bearing with supply holes inclined in the direction of rotation has been presented. In this bearing, viscous frictional loss is thought to be reduced since this mechanism provides gas flow in the rotational direction. This study reseach practical utillty and the characteristics of this bearings by using a a computational fluid dynamics analysis. This report presents the change of dynamic characteristics of bearings for rotation.