Temperature lines of the dry bulb are highlighted in green and Dry bulb temperature axis is highlighted( red).Here temperatures are numbered by 5 by 5 and Bottom line of the graph indicate temperature values of the dry bulb.So we cannot use this psychrometric chart to find relativeĭry bub axis includes in the bottom of the chart.
The total pressure and psychrometric chart design pressure is not same. The total pressure in the room is 0.89214 * 10 5 Pa. And you are said to find relative humidity of a You are provided a psychrometric chart which is designed for 1.01325 * 10 5 Pa. Total pressure is also called as barometric pressure.ĭesign pressure ( total pressure of air, P T) is the sum of dry air pressure (P da) and partial pressure of Is 1.01325 * 10 5 Pa, we can only read values related to that pressure. If design pressure (total pressure) of psychrometric chart The defined pressure is displayed on the psychrometric chart. Total pressure of air is changed in place to place. Psychrometric chart is designed for a defined pressure (total pressure). Locations of axes, we look to do several examples and problems to understand psychrometric chart exactly. Properly study axes of psychrometric chart with figures and get an idea, where different axes are located. In this tutorial we first study axes of psychrometric chart, then questions and examples are discussed. NOTE: Before understanding the psychrometric chart, you should have a good knoledge Psychrometric charts are extensively used in air-conditioningĮxample: When dry bulb temperature and wet bulb temperature of air are known, we can calculate absolute humidity, relative humidity and enthalpy.Temperature lines, constant enthalpy lines and constant specific volume lines. Furthermore, it also illustrates the constant relative humidity curves, constant wet-bulb.
Wet-bulb temperature scale is indicated on the saturated curve (relative humidity