A javascript library for psychrometric calculations. See the viewer here.
Psychrometry is a field of engineering for determining the properties of gas-vapor mixtures. This is a concern when designing ventilation systems; especially for industrial paint application processes, where providing air at the proper temperature and humidity is vital for achieving the proper finish. Psychrometric Charts are extremely useful tools that give a visual representation of how changing a single property of the mixture affects other properties. Psych.js powers an elevation-adjusted Psychrometric Chart Viewer for this purpose.
psych.js is composed of 4 main components: calculations, points, point builders, and mixed flows.
These are all calculations needed to determine different properties of moist air. Calculations are based on ASHRAE IP equations and were originally written by Jim Pakkala, PE in VBA and were then translated into this javascript library by David Jackson.
Psychrometric points are points on the psychrometric chart that contain the following psychrometric properties:
- Elevation
- Atmospheric Pressure
- Dry bulb temperature
- Wet bulb temperature
- Humidity Ratio
- Relative Humidity
- Enthalpy
- Dew point temperature
Point builders are simple builders that are used to create points. There are only three properties needed to calculate the rest of the psychrometric properties: elevation and any two of the other point properties.
Currently there is no implementation for calculating a point given the wet bulb temperature and enthalpy, this feature still needs to be developed.
Still under development