Example 01: Values from 'tdb' and relative humidity 'r'

The answers (where available) from the worked example problem are given in the 3rd column in the custom table at the top of the slide image in IP units. It is assumed in this trail that:

In the course PDF for 'CED Engineering: Air Conditioning Psychrometrics (A.Bhatia)' the term "enthalpy (h)" usually refers to the mass-specific enthalpy per dry air (in CoolProp notation 'Hda')

In the custom table at the top, where the specific enthalpy conversions from SI units to IP have been deliberately naively performed (as a counter example) using a simple scaling factor - instead of considering the reference offset between SI specific enthalpy and IP specific enthalpy - the values are indicated in the 1st column with an orange warning frame, and depart significantly from the correct answers. This is explained further under:

GOTCHA: Mathematica: Specific enthalpy conversion J/kg to Btu/lb: Does not consider a possible "total" enthalpy reference offset vs 0 °C or 0 °F respectively

The Webel Psy library has functions for more accurate conversion from SI specific enthalpy to IP specific enthalpy, however, be aware that there are lots of different variations of British Thermal Units in use!

Webel: Psy/MPsy: Psychrometrics for Mathematica: For Imperial Units (IP), International British Thermal Units (Btu) are assumed

Below the custom table, the same values generated automatically by a Webel MPsy object (via the CoolProp wrapper for Mathematica) are shown, and then the state position on psychrometric charts in both °F and °C.

An option $opt$psy$doShowAsIP specifies whether the chart should use Imperial Units (°F):

Webel: Psy/MPsy: Psychrometrics for Mathematica: Convention: Option variable names are prefixed with '$opt$psy'

The example uses a Mathematica virtual function Map &/@ over option values {True,False} to output the charts both in °F and °C.

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Example 02: Values from dry bulb temperature 'tdb' and wet bulb temperature 'twb' (sling psychrometer)

Notes

[COMPLICATION, GOTCHA, TIP]{INFORMATIVE} GOTCHA: Mathematica: Specific enthalpy conversion J/kg to Btu/lb: Does not consider a possible "total" enthalpy reference offset vs 0 °C or 0 °F respectively

[CONVENTION]{STRICT} Webel: Psy/MPsy: Psychrometrics for Mathematica: For Imperial Units (IP), International British Thermal Units (Btu) are assumed

[ASSERTION, GOTCHA, WARNING]{INFORMATIVE} In the course PDF for 'CED Engineering: Air Conditioning Psychrometrics (A.Bhatia)' the term "enthalpy (h)" usually refers to the mass-specific enthalpy per dry air (in CoolProp notation 'Hda')

[TIP] TIP: If your browser can't zoom in on large tutorial trail slide images in the tutorial trail image viewer, open the slide image in a separate tab then zoom in there

[NAMING, PATTERN, POLICY]{STRICT} Webel: Psy/MPsy: Psychrometrics for Mathematica: Convention: Option variable names are prefixed with '$opt$psy'

Snippets (quotes/extracts)