Bulk Temperature for Bodies of Various Shapes

Let us compare the approximate dependence (4.2.15) with some well-known exact results on heat exchange for nonspherical bodies. 

we consider a parallelepiped with sides L, L2, and L3. The solution of the corresponding three-dimensional problem (4.2.1)-(4.2.3) can be constructed by separation of variables and results in the following formula for bulk temperature [277]  

Comparison of exact and approximate values of bulk temperature (T) for bodies of various shape 

Mass and Heat Exchange Between Particles of Various Shape and a Stagnant Medium 

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