Cylindrical general differential equation of conduction

amish99
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Homework Statement


Desperate help needed on the derivation of the differential equation on conduction on a clyinder, i have come close to the answer and working with the co-ordinates scale of T(r,0,z).


I am sure that i have made a simple mistake but am blind to it right now, i have derived the equation for a square no problem and when i sub in the values for that of a cylinder i get into difficulties, any help would be appreciated
 
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You cannot use the equation for a rectangle when considering a cylinder; use the corresponding expressions in cylindrical coordinates instead. Solutions to the first are sines and cosines, the other are Bessel functions. (Hint: take a look in the text for your class.)

Edit: clean up wording
 
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