KURENAI : Kyoto University Research Information Repository

=
2
uR
(NFr)R=A ,RR= 1 .(96)
(Nf)Rd (ft) Rai(a0)2
R =l'(97)
ao2
(No)R = KRa i R= 1 .(98)
The drift flux number can be automatically satisfied-, if tiie contribution
/of the local slip is small in comparison with the slip due to the transverse
velocity and void profiles. When the local slip, i.e., the second term on
R.N.S. of Eq. (90), is the dominant factor for the relative motion, the sim-
ilarity requirement is uR = 1 which is a rather severe restriction. Hence
from (Nd)R = 1 one obtains,
Distribution Controlled Slip ~ Automatically Satisfied
Local Slip Controlled -} uR = 1
For most ,cases the first condition applies. Even in the second case, the distortion
of the velocity will introduce limited changes in the void-quality
relation. Therefore, in the following analysis the first condition will be
assumed.
From Eqs. (92) to (93), it is evident that basically the similarity in
terms of the vapor quality is satisfied. Thus
xR = 1 .(100)
And from Eq. (99) this implies that the void similarity also exists,
aR = 1 .(101)
Hence, excluding the friction similarity conditions, it is required that
355
•
(99)