4 replies to this topic

[breizh]

HI ,
What is the meaning of partly co current and partly counter current ?

Basic equation on heat transfer : heat transfer on both side ( cold & hot are equal)
1) M*cpcold *( Tcold out - Tcold in) =m*cphot * ( Thot in -Thot out) =Q
overall :
2) Q=U*A*Y*Dt ml(log mean)

from equation 1 you will get Tcold out
from equation 2 you will get A after calculating Dt ml with Y corection factor refering to counter current

Hope it helps
Breizh

[Art Montemayor]

Tshepang:

I haven't read all your calculated answer, but you have made an oversight in not specifically addressing Breizh´s question: what specific pass arrangement(s) do you have on the shell and tube side? Without this specific information, you cannot generate the required "F" factor in order to modify the Log Mean Temperature Difference (LMTD).

You should address the question and supply at least a sketch of the exchanger, clearly showing the passes. The temperature vs. distance curve you supply in your solution is that of a pure counterflow exchanger. I frankly don't have even a vague idea of what you mean by "Reversed, Mixed or Cross-Flow" just like I don't know what "partly co current and partly counter current" flow means. What country are you in or where have you obtained your technology descriptions? This could help us understand what you are trying to describe.