Subcooled Enthalpy Values?

[Calvin Becker]

Does anyone know where I can find liquid subcooling enthalpy values in excel format? We need this too complete our Visual Monitoring PCB that we use to measure fridge efficiency in KW/TON.

Calvin Becker
http://www.visualmonitoring.com

[Prof Sporlan]

One can use saturated liquid enthalpy values at the subcooled liquid temperature and obtain adequate accuracy. If one wishes to calculate subcooled liquid enthalpy values as accurately as possible, many of the equations of state developed for the various refrigerant are valid in the compressed liquid region. As the Prof recalls, these equations of state must conform closely to the Maxwell criteria.

Another approach is to interface your Excel file with the NIST RefProp DLL. The VBA code necessary to do this may be a bit of a chore, but the Prof has successfully done this in C++.

It is worth noting that one can write theromdynmaic property calculations in VBA that can be easily called in an Excel spreadsheet.

[shogun7]

Just curious if this might be of interest to you>
http://www.ornl.gov/~webworks/cppr/y2003/rpt/117000.pdf

[Calvin Becker]

Thanks for the above paper.. very good.

[Erik Detroit]

Calvin,
Which refrigerant, and what kind of accuracy are you trying to achieve in the calculations?