Investigation into the flow-induced instability of high-pressure rotors or large steam turbines

Thesis/Dissertation · Fri Jan 01 00:00:00 EST 1988

OSTI ID:5268327

Thomas, J P

The flow-induced instability of high-pressure rotors of large steam turbine generators has been a world-wide problem, and the subject of some controversy regarding the primary phenomena and major influencing parameters. In this study a simple one-dimensional model for the flow in a labyrinth seal was developed and solved for the linear dynamic coefficients. Dimensional analysis was employed to identify the major influencing parameters. The theoretical values for the dynamic coefficients were compared with published test data and found to be in qualitative agreement. Parametric studies were performed on typical sealing geometries to provide insight into the influence of the major design parameters on the aerodynamic excitation forces affecting rotor-system instability. A computer program utilizing the finite-element method was developed for considering the effect of the flow-induced forces on the damped natural frequencies and linear stability of complex rotor systems. System damping was calculated for several high-pressure rotor designs and results compared with actual operating experience. The importance of the various system components (i.e. seals, blading, bearings, etc.) with regard to the overall system stability was evaluated by means of the relative energy per cycle.

• Research Organization: Pennsylvania Univ., Philadelphia, PA (USA)
• OSTI ID: 5268327
• Resource Relation: Other Information: Thesis (Ph. D.)
• Country of Publication: United States
• Language: English

Related Subjects

20 FOSSIL-FUELED POWER PLANTS
42 ENGINEERING
ROTORS
INSTABILITY
STEAM TURBINES
COMPUTER CODES
DAMPING
DESIGN
FINITE ELEMENT METHOD
FLOW MODELS
HIGH PRESSURE
PARAMETRIC ANALYSIS
MACHINERY
MATHEMATICAL MODELS
NUMERICAL SOLUTION
TURBINES
TURBOMACHINERY
200104* - Fossil-Fueled Power Plants- Components
420200 - Engineering- Facilities
Equipment
& Techniques