DEVELOPMENT OF AERODYNAMIC FOIL JOURNAL BEARINGS FOR A HIGH-SPEED CRYOGENIC TURBOEXPANDER

The research presented in this paper is aimed at the development of ae rodynamic foil journal bearings applying to a small high speed cryogen ic turboexpander. A small high speed cryogenic turboexpander is design ed. Attention has been paid to the study of the effect of foil stiffne ss on the vibration performance of bearings. From rotation tests, it i s clear that, with the proper choice of foil stiffness, the foil beari ng presented here can possess sufficiently high stability. The maximum rotational speed obtained is greater than 230 000 rpm. Therefore, owi ng to its simplicity and high performance, this type of foil journal b earing can hopefully be applied to a small high speed cryogenic turboe xpander. (C) 1997 Elsevier Science Ltd.