KURENAI : Kyoto University Research Information Repository

a
j* 99 =jagOp1/4(3) 2
pg
where a, g and Op are the surface tension, acceleration due to the
gravity, and difference between the gas and liquid densities,
respectively. In Eq. (2), CK must be determined from experimental data.
However, it has been found that the value of CK depends on the distance
from the interface. Although Eq. (2) shows the effects of velocity and
pressure on Efg, it does not give any information on the effect of height,
which is important in the momentum controlled region.
Sterman [40] correlated the experimental data of entrainment for
steam water systems at pressures from 0.1 MPa to 18 MPa, and proposed a
dimensionless correlation. His correlation depends on the average void
fraction in the pool, therefore, he has also proposed several void
fraction correlations applicable to the problem. For a reasonably large
vessel satisfying the condition given by
*MO*2(4)
D> 260 ,
where the dimensionless diameter of vessel DH is given by
DH = DH RI-76 4)-g(5)
the Sterman correlation can be simplified to
fg = 6.09 x 10jh(6) 9*2.76*-2.3 (PyO.26 '2.21.1E
Here the dimensionless height h* is given by
h= h/'l-----a90p(7)
Y and the liquid viscosity number Nuf based on liquid viscosity of is given
by
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