Webel: Mathematica: CONVENTION: A prefix '$doc' indicates a documentation String for each primary variable/quantity (argument or output)

$doc$psy$mDot$a = vDoc[
 "mDot$a",
 "Mass flow rate of the dry air component (constant between states under steady state)."
];

$doc$psy$mDot$wat$i$g = vDoc[
 "mDot$wat$i",
 "Mass flow rate of water VAPOUR (gas) added TO the humid air mixture."
];

$doc$psy$w1 = vDoc[
 "w1",
 "Humidity ratio of State1 (initial)."
];

$doc$psy$w2 = vDoc[
 "w2",
 "Humidity ratio of State2 (final)."
];

Note how the documentation String is generated via a utility method vDoc that formats the variable name and documentation String (or Strings) thus:

$doc$psy$mDot$a

- mDot$a: Mass flow rate of the dry air component (constant between states under steady state).

This convention works together with: