The following parameters must be
supplied by the user
ANfin Number of fins per unit length
FINOD Fin outer diameter
FINT Fin thickness
Nrow Number of tube rows
Pl Lateral
pitch of the tube arrangement
Pt Transverse
pitch of the tube arrangement
TTin Tubeside inlet temperature
Tain Airside inlet temperature
Wair Mass flow rate of air.
Wtube Mass flow rate of tube-side fluid
Calculation
steps (single phase)
1. Estimate the heat duty Q
Let Cpair = Heat capacity of air at the air inlet
temperature
Let Cptube = Heat capacity of tubeside fluid at the tube
inlet temperature
Let Cmin = Minimum of WairCpair and WtubeCptube
Q = 0.7Cmin (TTin - Tain) (1)
2. Estimate the outlet temperatures
3. Estimate the airside and tubeside outlet
temperatures of each CV
By
linear interpolation from the outlet temperatures leaving the air cooler.
4. Estimate the pressure drop of each CV
- By using the known velocity,
temperature at the inlet to each CV
5. Calculate the overall heat transfer
coefficient at each CV
- Calculate air side heat transfer
coefficient
- Calculate tubeside heat transfer
coefficient
- Calculate the overall heat transfer coefficient
6. Calculate the airside and tubeside
outlet temperatures of each CV
- By using the energy balances on
each CV
7. Calculate the pressure drop of each CV
- By using the momentum and
materials balances.
8. Repeat steps 5-7 until the temperatures
converge
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