Additively Manufactured Hydrostatic Tilting Pad Journal Bearings: Measurements of Static Load Characteristics with Liquid Nitrogen

Abstract

In recent years, additive manufacturing (AM) has received extensive attention [1, 2] due to its reliability in integrating multiple orifices into hybrid tilting pad journal bearings. Prior studies have evaluated the performance of hydrostatic journal bearings and hydrostatic thrust bearings fabricated using AM [3-7]. In this study, comprehensive measurements are presented for the static load characteristics of additively manufactured hydrostatic tilting pad journal bearings (AMHB). Additionally, a procedure for Direct Metal Laser Melting (DMLM) fabrication is detailed. AMHB features multiple orifices, angled injections, and compliant dampers to improve rotordynamic stability. The static load characteristics of AMHB are estimated by measuring cryogenic fluid liquid nitrogen pressurized into the test bearings. The focus of this work is on comparing the static load characteristics of AMHB and hydrostatic journal bearings, which have similar diameters and lengths. The work highlights the potential of using AM for the fabrication of hydrostatic tilting pad journal bearings that improve rotordynamic stability, thus advancing the application of additive manufacturing to fluid journal bearings.