calc_overallheattransfercoefficient_fromNTU

pychemengg.heattransfer.heatexchangers.calc_overallheattransfercoefficient_fromNTU(NTU=None, area=None, Cmin=None)

To compute overall heat transfer coefficient (U) from NTU

Parameters

NTUint or float

Number of transfer units of heat exchanger.

areaint or float

Surface area of heat transfer for exchanger.

Cmin: `int or float`

Minimum heat capacity rate.

Returns

Overall heat transfer coefficient (U)int or float

See also

pychemengg.heattransfer.heatcommonmethods.calc_overallheattransfercoefficient

Notes

The following formula is used.

\[U = \frac {NTU \hspace{2pt} C_{min}} {A_{surfacearea}} \]

where:

NTU = number of transfer units for the heat exchanger

\(C_{min} = \dot{m} c_p\) = smaller of the two capacity rates for the two fluids in the heat exchanger

\(\dot{m}\) = mass flow rate of the fluid

\(c_p\) = specific heat of the fluid

\(A_{surfacearea}\) : Heat transfer surface area of the exchanger

U = overall heat transfer coefficient

References

[1] Yunus A. Cengel and Afshin J. Ghajar, “Heat And Mass Transfer Fundamentals and Applications”, 6th Edition. New York, McGraw Hill Education, 2020.

Examples

First import the module heatexchangers.

>>> from pychemengg.heattransfer import heatexchangers as hx 
>>> hx.calc_overallheattransfercoefficient_fromNTU(NTU=0.651, Cmin=5.02e3, area=5.11)
639.5342465753424