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[kkala]

Godfish fillets originially at 10 degree celcius are packed to a thickness of 102 mm. Ice is packed on both sides of the fillets and wet-strength paper separates the ice and fillets. The surface temperature of the fish can be assumed as essentially 0 degree celcius. Calculate the time for the center of the fillets to reach 2.22 degree celcius and the temperature at this time at a distance 25.4mm from the surface. k=0.571 W/mK, rho=1052 kg/m3, and Cp=4.02kJ/kgK
So my question is... what is the heat transfer coeffcient for this problem??
I'm guessing that I have to make some kind of assumption for the heat transfer coefficient and my best guess is that the heat transfer coefficient is a really large number relative to the thermal conductivity so k/hx1 is essentially zero.
If I find out what the heat transfer coefficient is then I know how to solve the rest of the problem so... please help me!!

My understanding is same as yours: mentioned heat transfer coefficient is assumed very large, and this is clearly indicated by the text of the problem saying "surface temperature of the fish can be assumed as essentially 0 oC", that is same temperature as of melting ice. The separating "wet strength" paper does not affect heat transfer coefficient (at least this is the assumption instructed by the text), but ascertains that codfish does not contact resulting water, which would have complicated the case.
So the problem is reduced to one of unsteady state one dimensional conduction (m=0, per Perry 7th ed, sect 5, p. 5-11), with 0 oC surface temperature at both sides of the slab.

Edited by kkala, 14 February 2010 - 05:02 AM.