| OCR Text |
Show 2.1.12 flow rates generated on and inside the core k, k R dR C"(r) = - E p c (-V - ^ , R,<r<R, , (23) n=K g n g n r dt k k which includes the water vapour generated on the core T=373 K (if T <373 K) and the volatiles generated on different cores. By substituting the result (23) into the equation (22) we obtain in dimensionless form the equation that describes the temperature distribution between two successive moving cores k(*r H» + fk(Fo>H • xk<x<xk+i ,(24) k - dX where f, (Fo) = I G ,X - - , G , =p c ao/A. . The solution is k _, nk n ,_, nk gn gn k n=K dFo * ^ 6 - ek = (ek+rek) F k (FO'x)' Xk<x<\+1 (25) 1 - exp{-f (Fo)g (x)} where F (Fo,x) = (26) 1-exp{-fk(Fo)gk(Xk+1)} x 1 where g (x) = / -=- dx X, x k = x-X, , when r = 0 for a plate = ln(x/X, ), when r = 1 for a cylinder 1_ 1 k ' x ' when r=2 for a sphere X If there is no flow of volatiles or steam between the cores Xk and XR + 1 , fR(Fo)=0 and gk( x) gk(Xk+1 Fk(Fo,x) = - (27) The equation (25) (or (27)) is of the same form as the stationary temperature distribution between two surfaces that are kept at temperatures 6k and 6 and have a gas flow between them, but now the surfaces are moving. |
