Calculating U - in heat transfer
Calculating U - in heat transfer
(OP)
Until now I look up a vendor catalogue and search for U for a heat medium and process conditions - its usually a range. I take the lowest and find the corresponding area required for heat transfer. Is this the best way of doing it? Load of thanks





RE: Calculating U - in heat transfer
I2I
RE: Calculating U - in heat transfer
thanks
RE: Calculating U - in heat transfer
choose heat exchanger and pick the calculation that you want.
Regards
RE: Calculating U - in heat transfer
rmw
RE: Calculating U - in heat transfer
What about factors such as type of exchanger, pressure and temperature ranges (process and mechanical effects), geometry details, fluid allocation ("tube" or "shell" side), flow arrangement (e.g., parallel, crossflow or counterflow), number of passes, possible fouling effects, safety and corrosion considerations, unit physical location, etc.?
Selecting a unit just on the estimated U values could only serve to make ballpark preliminary cost estimates, surely not to design and rate it.
RE: Calculating U - in heat transfer
Sicne starting this thread I figured out that U is inverse of resistance. When asked to confirm a heat exchange 'A' I would take the lowest of the U and calculate 'A' to see if it is in the ball part of lowest U - this ensures in a worst case scenario that exchanger will still perform.
thanks
RE: Calculating U - in heat transfer
I2I
RE: Calculating U - in heat transfer
RE: Calculating U - in heat transfer
regards
RE: Calculating U - in heat transfer
from LUDWIG handbook as a guide
then calculate heat transfer coefficients of each side
then overall U from HEAT TRANSFER handbooks
with consideration of accuracy of relations
and fouling.
RE: Calculating U - in heat transfer