J. Krysa et Aa. Wragg, FREE CONVECTIVE MASS-TRANSFER AT UP-POINTING PYRAMIDAL ELECTRODES, International journal of heat and mass transfer, 40(15), 1997, pp. 3717-3727
A limiting current technique was used for the measurement of the free
convective mass transfer rate at entire upward pointing pyramids. The
mass transfer rate at a single inclined pyramidal surface was correlat
ed by the equation: Sh(L) = 0.828(Ra-L,Ra-theta)(0.25) for the Ra-L,Ra
-theta range 1 x 10(7) to 2 x 10(11). It was found that the mass trans
fer rate for the combination of all inclined faces was lower than that
for the single inclined surface. The down-pointing horizontal base su
rface has a strong influence on the total mass transfer rate for entir
e upward pointing pyramids. The experimental total mass transfer data
were correlated using a method which includes an interference factor t
aking account of the fact that the three inclined triangular faces are
exposed to fluid which has already been depleted in copper ions as it
flows upward from the base. The dependence of the interference factor
on the aspect ratio of the pyramid (L/b) was not so strong as for ver
tical cylinders or down-pointing pyramids. (C) 1997 Elsevier Science L
td.