Session: 23-08 Annular Seals

Paper Number: 151421

Analysis of a Self-Contained ISFD With Circumferential Arc-Grooves Being Used As Oil Flow Restrictors 

Roller bearings are widely used in rotating machinery for easy installation and low maintenance costs. However, because roller bearings do not provide enough damping, the speed of a roller-bearing supported shaft is limited to under the first critical speed. If the design requires the shaft to run above the critical speed, an external damping source, such as a squeeze film damper (SFD), is often used. Most SFDs need a few liters per minute of oil to fill the damper clearance and often share the same oil circulation system with other mechanical components such as fluid film bearings, gears, etc. However, some applications require oil-free conditions, where an oil circulation system is not available. In such a case, the lubricant must be self-contained, and the SFD needs to be hermetically sealed. This paper introduces a new concept for a sealed SFD using circumferential arc grooves as oil flow restrictors. The new design is similar to that of an integral squeeze film damper (ISFD) featuring four circumferentially arranged individual fluid film lands and two end plates to enhance the generation of fluid film dynamic pressure. Each end plate of the new SFD is sealed by two O-rings installed on the damper end face but at different radius. The adjacent damper lands are connected by a shallow circumferential arc groove, which is used as an oil flow restrictor during dynamic operation conditions. Dynamic load tests and CFD analysis show that the new sealed SFD produces a similar amount of damping compared to that of a conventional lubricated ISFD of the same size.

Presenting Author: Tingcheng Wu Air Products

Presenting Author Biography: Dr. Tingcheng Wu is currently the manager of Mechanical and Systems Depart at Rotoflow (An Air Products business). He leads the mechanical design, project execution, and system packaging teams in Rotoflow (Air Products) Before that, he was a Senior Rotordynamic R&D Engineer in Siemens Research and Development Department. He provides expertise in rotordynamic related research and development projects, as well as diagnose and support filed vibration problems. Dr. Wu is also responsible for reviewing and approving the rotordynamic analysis for all new equipment. He got his Ph.D. degree from Texas A&M University, where he worked for the Turbomachinery Laboratory for four and a half years. His research focuses on the rotordynamics/vibrations of turbomachines (compressors, pumps, turbines).

Authors:

Xueliang Lu Hunan SUND Technological Corporation
Tingcheng Wu Air Products
Su Zheng Hunan SUND Technological Corporation
Yabin Zhang Hunan SUND Technological Corporation