M. Pakdemirli, CONVENTIONAL AND MULTIPLE DECK BOUNDARY-LAYER APPROACH TO 2ND AND 3RDGRADE FLUIDS, International journal of engineering science, 32(1), 1994, pp. 141-154
A general analysis of boundary layers of second and third grade fluids
are made in which the conventional as well as the multiple deck struc
tures are investigated. It is shown that for second grade fluids only
conventional two deck structure exists and a multiple deck boundary la
yer is impossible. For the third grade fluids, three conventional boun
dary layers are formulated. In the first one, we retain all the terms
whereas in the second one the viscous, and in the third one, second gr
ade terms come out to be negligible compared to other terms. A similar
ity solution is presented for the third case. Under some restricted co
nditions, it is shown that quadruple decks exist for the third grade f
luids. For the lower deck equations to be matched with the middle deck
equations, a decaying solution should exist, and this further require
s that 2alpha1 + alpha2 = 0 where alpha1 and alpha2 are the material m
oduli for third grade fluids.