AIR- SEA INTERA('TIONS
399
E
N
t 075 050025 O,, OM O, , O,, Ow, 0, O8 0 7 0, 0 3 O4 0,
0,
(F-Fo)/(F,,,- F,)
I-ici 7 Evolution of dimenaionle5s humidity profile\
Average evaporalion Nusselt numbers determined in that way (for the large
facility) art' plotted in Fig. 8 as a function of length Reynolds numbers,
together with results obtained in the small facility and in other laboratories
(Lai and Plate. 1969; Delvaux, 1967). Although these data are very preliminary, they gather themselves reasonably well, in log-log coordinates, around a
line with equation
Nu = 0.0X Re"''.
Use has dso been made of isotopic techniques to investigate the evaporative process i n the small facility. The measured fractionation rates of various
isotopes tend to confirm the previously proposed dependence of the eddy
mass diffusivity coefficient, as varying with the one-half power of the molecular diffusivity coefficient (Merlivat and Coantic, 1972).
Fici. X. Averngc cvirporiltlon Nusselt numbers. Nu = j,)L;p!/ At. as a function ot'length
Reynolds nurnberb. Re = IsL'r..