Abstract

Two-phase cross-flow exists in many shell-and-tube heat exchangers. The U-bend region of nuclear steam generators is a prime example. Testing in two-phase flow simulated by air-water provides useful results inexpensively. However, two-phase flow parameters, in particular surface tension and density ratio, are considerably different in air-water than in steam-water. A reasonable compromise is testing in liquid-vapor Freon, which is much closer to steam-water while much simpler experimentally. This paper presents the first results of a series of tests on the vibration behavior of tube bundles subjected to two-phase Freon cross-flow. A rotated triangular tube bundle of tube-to-diameter ratio of 1.5 was tested over a broad range of void fractions and mass fluxes. Fluidelastic instability, random turbulence excitation, and damping were investigated. Well-defined fluidelastic instabilities were observed in continuous two-phase flow regimes. However, intermittent two-phase flow regimes had a dramatic effect on fluidelastic instability. Generally, random turbulence excitation forces are much lower in Freon than in air-water. Damping is very dependent on void fraction, as expected.

1.
Axisa, F., Boheas, M. A., and Villard, B., 1985, “Vibration of Tube Bundles Subjected to Steam-Water Cross-Flow: A Comparative Study of Square and Triangular Arrays,” 8th International Conference on Structural Mechanics in Reactor Technology, Brussels, Belgium, Paper No. B 1/2, Aug.
2.
Carlucci
L. N.
, and
Brown
J. D.
,
1983
, “
Experimental Studies of Damping and Hydrodynamic Mass of a Cylinder in Confined Two-Phase Flow
,”
ASME Journal of Vibration, Stress and Reliability in Design
, Vol.
105
, pp.
83
89
.
3.
McQuillan
K. W.
, and
Whalley
P. B.
,
1985
, “
Flow Patterns in Vertical Two-Phase Flow
,”
International Journal of Multiphase Flow
, Vol.
11
, pp.
161
175
.
4.
Pettigrew, M. J., and Gorman, D. J., 1973, “Experimental Studies on Flow-Induced Vibration to Support Steam Generator Design, Part III: Vibration of Small Tube Bundles in Liquid and Two-Phase Cross-Flow,” Paper 424, presented at the International Symposium on Vibration Problems in Industry, Keswick, U.K., April 10–12; also, published as AECL Research Report AECL-5804, 1977.
5.
Pettigrew, M. J., and Knowles, G. D., 1992, “Some Aspects of Heat Exchanger Tube Damping in Two-Phase Mixtures,” ASME International Symposium on Flow-Induced Vibration and Noise, Vol. 1, Anaheim, CA, pp. 141–160.
6.
Pettigrew
M. J.
, and
Taylor
C. E.
,
1994
, “
Two-Phase Flow-Induced Vibration: An Overview
,” Survey Paper,
ASME JOURNAL OF PRESSURE VESSEL TECHNOLOGY
, Vol.
116
, pp.
233
253
.
7.
Pettigrew
M. J.
,
Taylor
C. E.
, and
Kim
B. S.
,
1989
a, “
Vibration of Tube Bundles in Two-Phase Cross-Flow—Part 1: Hydrodynamic Mass and Damping
,”
ASME JOURNAL OF PRESSURE VESSEL TECHNOLOGY
, Vol.
111
, pp.
466
477
.
8.
Pettigrew
M. J.
,
Kim
B. S.
,
Taylor
C. E.
, and
Tromp
J. H.
,
1989
b, “
Vibration of Tube Bundles in Two-Phase Cross-Flow—part 2: Fluidelastic Instability
,”
ASME JOURNAL OF PRESSURE VESSEL TECHNOLOGY
, Vol.
111
, pp.
478
487
.
9.
Pettigrew, M. J., Taylor, C. E., and Yasuo, A., 1994, “Vibration Damping of Heat Exchanger Tube Bundles in Two-Phase Flow,” Welding Research Council Bulletin No. 389, New York, NY, pp. 1–41.
10.
Rogers, R. G., Taylor, C., and Pettigrew, M. J., 1984, “Fluid Effects on Multi-Span Heat Exchanger Tube Vibration,” ASME PVP Conference, San Antonio, TX, ASME Publ. H00316, Topics in Fluid Structure Interaction, pp. 17–26.
11.
Taylor, C. E., 1992, “Random Excitation Forces in Tube Arrays Subjected to Two-Phase Cross-Flow,” ASME International Symposium on Flow-Induced Vibration and Noise, Vol. 1, Anaheim, CA, pp. 89–107.
12.
Taylor
C. E.
,
Pettigrew
M. J.
,
Axisa
F.
, and
Villard
B.
,
1988
, “
Experimental Determination of Single and Two-Phase Cross Flow Induced Forces on Tube Rows
,”
ASME JOURNAL OF PRESSURE VESSEL TECHNOLOGY
, Vol.
110
, pp.
22
28
.
13.
Taylor
C. E.
,
Pettigrew
M. J.
,
Currie
I. G.
, and
Kim
B. S.
,
1989
, “
Vibration of Tube Bundles in Two-Phase Cross-Flow—Part 3: Turbulence Induced Excitation
,”
ASME JOURNAL OF PRESSURE VESSEL TECHNOLOGY
, Vol.
111
, pp.
488
500
.
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