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errors. In view of this, one can obtain Eq.(75) by substituting Eq.(70)<br />

into Eq.(74)<br />

EHCpp N<br />

This equation can be rewritten as<br />

7q w<br />

(T - T )S-1/7y-6/7,(75)<br />

w cct<br />

T-<br />

wE<br />

T<br />

.7 ------7qw1/7 y6/7(76)<br />

HCpp t<br />

For the case of Pr = 1, the turbulent diffusivity of heat, EH, can be app-<br />

roximated by the turbulent diffusivity of momentum, c., that is,<br />

From Eqs.(73),(76) and (77), one obtains<br />

EH = EM •(77)<br />

T- T= 33.82 u Cpw-------Re°*2 (St)1/7(78)<br />

wco co pv<br />

Under steady state condition and .Pr = 1, thermal boundary layer has appro-<br />

ximately same thickness as velocity turbulent boundary layer, then (St/S v)<br />

= 1. Therefore, Eq.(78) gives, of course, the same result as Reynolds<br />

analogy.<br />

Substituting Eqs.(60) and (61) into Eq.(3) and integrating,from 0 to<br />

t, one obtains,<br />

8/7<br />

2(T S ) + ua(T -------t)clw(79)<br />

8 3t' w t 72ax wS1/7C<br />

pp ,<br />

v In Eq.(3), thermal diffusivity, a, should be replaced by (a+EH). However,<br />

in the limit of y -> 0, one obtains,<br />

lim (a +EH)(<br />

y<br />

40pp<br />

131<br />

80)

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