A subsynchronous vibration problem with a large water injection pump was solved in 1974 by modifying the discharge piping transition to a long taper configuration. This paper describes a quantitative theory based upon the dynamic modeling of the pump rotor and piping system. The model successfully duplicates the experimental results of the pump instability and reproduces the subsynchronous vibration described in the original paper. The analysis results in a log decrement of the system that is dependent upon the time delay of the acoustic pulsation. It shows that the system can be driven unstable for acoustic path lengths that are much less than the quarter wavelength. The analysis also shows the log decrement is minimized when the time delay is equivalent to exactly that of one eighth wavelength of the resonant frequency of the pump.

Benade, A. H., 1973, “The Physics of Brasses,” Scientific American, Vol. 229, No.1.
Bolleter, U., Buehlmann, E., Eberl, J., and Stirnemann, A., 1992, “Hydraulic and Mechanical Interactions of Feedpump Systems,” TR-100990, Research Project 1884-10, Electric Power Research Institute.
D. W.
, “
Dynamic Analysis of Turbulent Annular Seals Based on Hirs’ Lubrication Equation
ASME Journal of Lubrication Technology
, Vol.
, pp.
Corley, J. E., 1978, “Subsynchronous Vibration in a Large Water Flood Pump,” Proc. 7th Turbomachinery Symposium, Texas A&M University, College Station, TX.
Pierce, A., 1989, Acoustics—An Introduction to Its Physical Principles and Applications, Acoustical Society of America.
Schwartz, R. E., and Nelson, R. M., 1984, “Acoustic Resonance Phenomena in High Energy Variable Speed Centrifugal Pumps,” Proc. 1st International Pump Symposium, Texas A&M University, College Station, TX.
Sparks, C. R., and Wachel, J. C., 1976, “Pulsations in Liquid Pumps and Piping Systems,” Proc. 5th Turbomachinery Symposium, Texas A&M University, College Station, TX.
Tao, L. N., and Donovan, W. F., 1955, “Through-flow in Concentric and Eccentric Annuli of Fine Clearance With and Without Relative Motion of the Boundaries,” Transactions of the ASME, Vol. 77.
“TUTSIMTM Block Diagram Simulation Language,” 1999, Tutsim Products, Palo Alto, CA.
This content is only available via PDF.
You do not currently have access to this content.