The dynamic stability behavior of a typical pilot-operated relief valve has been investigated both numerically and experimentally. The valve piston equation of motion has been solved in connection with the conservation equations of the oscillating flow in the attached riser. The boundary condition at the riser tip is of a choked flow type and had to be given special attention in oscillatory flows. Pertinent quasi-steady flow equations have been formulated to describe the different phases of relief along the piston lift. A model describing the process of pressure relief is described briefly, followed by a parametric study of the effects of various factors on the oscillation levels and characters. Field measurements were taken on an NFS 8 pilot-operated dual-outlet relief valve mounted on a riser assembly of L/D = 15 in a natural gas compressor station.

Issue Section:
Research Papers
Topics:
Pipeline risers, Risers (Casting), Valves, Flow (Dynamics), Pistons, Relief valves, Boundary-value problems, Compressors, Dynamic stability, Equations of motion, Manufacturing, Natural gas, Oscillations, Pressure
1.
Benedict, R. P., 1971, “Generalized Contraction Coefficient of an Orifice for Subsonic and Supersonic Flows,” ASME Journal of Basic Engineering, pp. 99–120.
2.
Bloxsidge
G. J.
,
Dowling
A. P.
, and
Langhorne
P. J.
,
1988
, “
Reheat buzz: An Acoustically Coupled Combustion Instability—Pert 2. Theory
,”
Journal of Fluid Mech.
, Vol.
193
, pp.
445
–
473
.
3.
Botros, K. K., and Petela, G., 1994, “Use of Method of Characteristics & Quasi-Steady Approach in Transient Simulation of Compressor Stations,” ASME Fluids Engineering Division Summer Meeting, Advances in Computational Methods in Fluid Dynamics, Lake Tahoe, Nevada, U.S.A., FED-Vol. 196, pp. 325–338.
4.
D’Netto
W.
and
Weaver
D. S.
,
1987
, “
Divergence and Limit Cycle Oscillations in Valves Operating at Small Openings
,”
Journal of Fluids and Structures
, Vol.
1
, pp.
3
–
18
.
5.
Dunn, G., 1991, “Safety Relief Valve Damage During Testing,” NGTL Internal Report.
6.
Emerson, G. B., 1966, “Safety Valve Operational Stability,” Anderson/Green wood & Co., Internal Report No 2–0089.
7.
Follmer, B., 1980, “Oscillating Functioning of Safety Relief Valves Generated by Their Inlet Geometry,” Flow Visualization 2, Proceedings of the 2nd International Symposium, Sept. 9–12, New York, pp. 203–208.
8.
Foy, C. E., Kiel, D. E. Jungowski W. J., 1993, “The Effect of Pressure Pulsation and Pilot Setting on the Performance of Pressure Relief Valves,” Society of Petroleum Engineers, Eastern Regional Meeting, SPE 26907, pp. 183–196.
9.
Krivosheev, A. G., 1988, “Stability of Steady State Operation of Safety Relief Valves,” UDC 621.646.4.001.5, pp. 81–84, Translated from Khimichskoe
10.
Munjal, M. L., 1987, Acoustics of Ducts and Mufflers, John Wiley, New York.
11.
MacLeod
G.
,
1985
, “
Safety Valve Dynamic Instability: An Analysis of Chatter
,”
ASME Journal of Pressure Vessel Technology
, Vol.
107
, pp.
172
–
177
.
12.
Masuda, F., 1985, “Dynamic Response Analysis of a Safety Valve With Transients of a Fluid System,” Transactions of the 8th International Conference on Structural Mechanics in Reactor Technology, Brussels, F1-(F2), pp. 53–58.
13.
Myers
M. K.
, and
Callegari
A. J.
,
1977
, “
On the Singular Behavior of Linear Acoustic Theory in Near-Sonic Flows
,”
Journal of Sound & Vibration
, Vol.
51
(
4
), pp.
517
–
531
.
14.
Nayfeh
A. H.
,
Shaker
B. S.
, and
Kaiser
J. E.
,
1980
, “
Transmission of Sound Through Non Uniform Circular Ducts with Compressible Mean Flows
,”
AIAA Journal
, Vol.
18
, No.
5
, pp.
515
–
525
.
15.
Nayfeh
A. H.
, and
Bouguerra
H.
,
1990
, “
Non-Linear Response of a Fluid Valve
,”
International Journal of Non-Linear Mechanics
, Vol.
25
, pp.
433
–
449
.
16.
Powell, W. W., 1971, “A Study of Resonant Phenomena in Pilot-Operated Safety Relief Valves,” Anderson Greenwood & Co., Internal Report #2-0175-51.
17.
Semeniuk, T., 1995, “Relief Valve Failure,” NGTL Internal Metallurgical Report.
18.
Thomann, H., 1976, “Oscillations of a Simple Valve Connected to a Pipe—Parts I, II and III,” Journal of Applied Mathematics and Physics (ZAMP), Vol. 27.
19.
Watton, J., 1983, “Dynamic Characteristics of a Single Stage Pressure Rate Controlled Relief Valve With Directional Damping,” ASME Winter Annual Meeting, Paper 83-WA/DSC-40, pp. 1–8.
20.
Watton, J., 1990, “The Stability and Response of a Two Stage Pressure Rate Controllable Relief Valve,” Journal of Fluid Control, pp. 50–66.
This content is only available via PDF.
Copyright © 1997
 by The American Society of Mechanical Engineers
You do not currently have access to this content.