Session: Poster Session

Paper Number: 162878

Revamping of a High-Speed Rotordynamic Test Rig for Cryogenic Hydrostatic Bearings 

Cryogenic fluid film bearings are recognized as critical components for rocket engine turbopumps in reusable launch vehicles. However, experimental studies on rotor systems supported by such bearings are quite rare. This study presents improvements to an existing experimental facility designed to measure the dynamic behavior of a rotating shaft system supported by cryogenic liquid nitrogen fluid film bearings. The facility was originally developed to investigate the rotordynamic characteristics of an electric pump. The shaft, designed to simulate the characteristics of the electric pump rotor, was driven by a 1.7 kW electric motor up to approximately 10 krpm. Due to inappropriate experimental procedures, the system experienced persistent pneumatic hammer instability, resulting in damage to the shaft and bearings. To expand its experimental capabilities, the facility underwent several improvements, including repair of the damaged components. The original electric motor was replaced with a 160 kW permanent magnet synchronous motor. Additionally, procedures for cooling the apparatus and supplying liquid nitrogen were revised to minimize pneumatic hammer instability. Twenty temperature sensors were added to continuously monitor the temperature of the housing, and bearing temperatures are now acquired using four T-type temperature sensors. Furthermore, the addition of four cryogenic accelerometers enables reliable vibration analysis. Future work will experimentally investigate the effects of various operating parameters of cryogenic fluid film bearings on the characteristics of the rotor system.

Presenting Author: Kyuman Kim Hanyang University

Presenting Author Biography: Graduate Research Assistant at Hanyang University

Authors:

Kyuman Kim Hanyang University
Keun Ryu Hanyang University