PSYCHROMETRIC CHART :- 

Psychrometry deals with the determination of the thermodynamic properties of moist air and the utilization of these properties in the analysis of conditions and processes involving moist air.

The basic coordinate grid lines of the chart are enthalpy, which slopes up to the left, and the humidity ratio (or specific humidity) which runs horizontal. Dry-Bulb temperature is illustrated by vertical lines uniformly spaced. Wet-Bulb lines slope similarly to enthalpy lines, but the slope increases as the temperature increases. Note that wet-bulb line is not parallel to an enthalpy line; this is because of the heat added to the air mixture by the moisture, as it changes from dry to saturated air. Relative humidity lines are curved, with the saturation line defining the upper boundary of the chart.

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