Psychrometric Chart - Barometric Pressure.
Definition
The barometric pressure is also known as atmospheric pressure. It is treated as a constant throughout an air conditioning plant..
Where it occurs
Psychrometric charts are drawn for a fixed barometric pressure - 1013 mbar for NTP, STP and SATP. Barometric pressure is the sum of the partial pressures of "dry air" and "steam" ( or water vapour).
Special features
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How to set it
A default value of 1013 mbar is set. You can edit the corresponding text box. Remember to set the pressure in mbar - four numbers to the left of any decimal point.
Restrictions, limitations and innaccuracy.
Losses/ gains of total pressure in the plant are ignored.
The theory
NA
Exercises
NA
Links
IAWPS Revised release .
NIST tables .