Abstract

Transient conjugate two-phase heat transfer during depressurization of pipelines containing flashing liquids is examined in this paper. A numerical model for transient flashing liquid flow in a pipe is formulated. The model takes into account the transient radial heat conduction and the forced convection effects. Numerical simulation of flashing two-component (propane and butane) flow is performed in order to investigate the effect of wall friction on the heat transfer conditions in the pipe. The simulation results are compared with predictions of the model that are based on a new formulation of energy equation proposed by the author in an early study. A comparison of the results obtained allows one to determine the range of applicability of the new energy equation formulation. A procedure is proposed for choosing an appropriate model for predicting transient conjugate two-phase heat transfer during releases of flashing liquids from pipes. A criterion of thermodynamic similarity for flashing liquids flows in pipes or channels is formulated. The proposed criterion provides the basis for selecting model fluids and for constructing experimental models of systems containing flashing (volatile) liquids with scaled thermodynamic conditions. An example of its use is given. [S0022-1481(00)02001-6]

1.
Sucec
,
J.
,
1975
, “
Unsteady Heat Transfer Between a Fluid With Time Varying Temperature and a Plate: An Exact Solution
,”
Int. J. Heat Mass Transf.
,
18
, pp.
25
34
.
2.
Sucec
,
J.
,
1981
, “
An Improved Quasi-Steady Approach for Transient Conjugated Forced Convection Problems
,”
Int. J. Heat Mass Transf.
,
24
, pp.
1711
1722
.
3.
Lin
,
Y. K.
,
Yin
,
C. P.
, and
Yan
,
W. M.
,
1991
, “
Transient Laminar Mixed Convective Heat Transfer in a Flat Duct
,”
ASME J. Heat Transfer
,
113
, pp.
384
390
.
4.
Lin
,
Y. K.
, and
Kuo
,
J. C.
,
1988
, “
Transient Conjugated Heat Transfer in Fully Developed Laminar Pipe Flows
,”
Int. J. Heat Mass Transf.
,
31
, pp.
1093
1102
.
5.
Chen
,
J. C.
,
1966
, “
Correlation for Boiling Heat Transfer to Saturated Liquids in Convective Flow
,”
Int. Eng. Chem. Process Design Development
5
, pp.
322
333
.
6.
Klimenko
,
V. V.
,
1988
, “
A Generalized Correlation for Two-Phase Forced Flow Heat Transfer
,”
Int. J. Heat Mass Transf.
,
31
, pp.
541
552
.
7.
Shah
,
M.
,
1976
, “
A New Correlation for Heat Transfer During Boiling Flow Through Tubes
,”
ASHRAE Trans.
,
82
, pp.
66
72
.
8.
Fairuzov
,
Y. V.
,
1998
, “
Blowdown of Pipelines Carrying Flashing Liquids
,”
AIChE J.
,
44
, pp.
245
254
.
9.
Fairuzov
,
Y. V.
,
1998
, “
Numerical Solution for Blowdown of Pipeline Containing Flashing Liquid
,”
AIChE J.
,
44
, pp.
2124
2128
.
10.
Richardson, S. M., and Saville, G., 1991, “Blowdown of Pipelines,” Proceedings of Offshore Europe 91, Aberdeen, U.K., SPE Paper No. 23070.
11.
Wallis
,
G. B.
,
1980
, “
Critical Two-Phase Flow
,”
Int. J. Multiphase Flow
,
6
, pp.
97
112
.
12.
Chen
,
J. R.
,
Richardson
,
S. M.
, and
Saville
,
G.
,
1995
, “
Modelling of Two-Phase Blowdown from Pipelines-II. A Simplified Numerical Method for Multi-Component Mixtures
,”
Chem. Eng. Sci.
,
50
, pp.
2173
2187
.
13.
Solorzano
,
M.
,
Barraga´n-Arroche
,
F.
, and
Bazua-Rueda
,
E.
,
1996
, “
Comparative Study of Mixing Rules for Cubic Equations of State in the Prediction of Multicomponent Vapor-Liquid Equilibria
,”
J. Phase Equilib.
,
122
, pp.
99
106
.
14.
McAdams
,
W. H.
,
Woods
,
W. K.
, and
Heroman
,
L. C.
,
1942
, “
Vaporization Inside Horizontal Tubes. II-Benzane-Oil Mixtures
,”
Trans. ASME
,
64
, pp.
193
200
.
15.
Collier, J. G., 1981, “Multicomponent Boiling and Condensation,” Two-Phase Flow and Heat Transfer in the Power and Process Industries, Bergels, A. E., Collier, J. G., Delhaye, J. M., Hewitt, G. F., and Mayinger, F., eds., Hemisphere, Washington, D.C., pp. 520–557.
16.
Stephan
,
K.
, and
Korner
,
M.
,
1969
, “
Calculation of Heat Transfer in Evaporating Binary Liquid Mixtures
,”
Chem. Ing. Technik.
41
, pp.
409
417
.
17.
Ransom, V. H., and Trapp, J. A., 1978, “RELAP5 Progress Summary,” PILOT Code Hydrodynamic Model and Numerical Scheme, Idaho National Engineering Laboratory Report No. CD-AP-TR-005.
18.
Patnakar, V. S., 1980, Numerical Heat Transfer and Fluid Flow, Hemisphere, Washington, D.C.
19.
Tam, V. H. Y., and Cowley, L. T., 1988, “Consequences of Pressurised LPG Releases: The Isle of Grain Full-Scale Experiments,” Proceedings of GASTECH 88, 13th International LNG/LPG Conference, Kuala Lumpur, pp. 2–25.
20.
Richardson
,
S. M.
, and
Saville
,
G.
,
1996
, “
Blowdown of LPG Pipelines, Process Environmental Protection
,”
Trans. Inst. Chem. Eng.
,
74
, pp.
235
245
.
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