Carrier psychrometric chart si units pdf

In practice, this is the reading of a thermometer whose sensing bulb is covered with a wet sock evaporating into a rapid stream of the sample air. Through a constant-pressure, ideal, adiabatic saturation process, that is, after the air has passed over a large surface of liquid water in an insulated channel. Wet-bulb temperature (WBT) is that of an air sample after it has The SI units for temperature are Kelvin other units are Fahrenheit. It is typically the x-axis, the horizontal axis, of the graph.

The thermophysical properties found on most psychrometric charts are: п‚·Дry-bulb temperature (DBT) is that of an air sample, as determined by an ordinary thermometer, the thermometer's bulb being dry. The chart graphically expresses how various properties relate to each other, and is thus a graphical equation of state. This property of air-water vapor systems simplifies drying and cooling calculations often performed using psychrometic relationships.ДЄ psychrometric chart is a graph of the physical properties of moist air at a constant pressure (often equated to an elevation relative to sea level). The psychrometric ratio of air-water vapor mixtures is approximately unity which implies that the difference between the adiabatic saturation temperature and wet bulb temperature of air-water vapor mixtures is small. Mixtures of air and water vapor are the most common systems encountered in psychrometry. The psychrometric ratio is an important property in the area of psychrometrics as it relates the absolute humidity and saturation humidity to the difference between the dry bulb temperature and the adiabatic saturation temperature. Humid heat is the constant-pressure specific heat of moist air, per unit mass of dry air. Ky = convective mass transfer coefficient, kg m-2 s-1 Hc = convective heat transfer coefficient, W m-2 K-1 It may be evaluated with the following equation

Product of mass transfer coefficient and humid heat at a wetted surface. Psychrometric ratio The psychrometric ratio is the ratio of the heat transfer coefficient to The most common system of interest, however, are mixtures of water vapor and air because of its application in heating, ventilating, and air-conditioning and meteorology. The term derives from the Greek psuchron meaning 'cold' and metron meaning 'means of measurement'Д¬ommon applications The principles of psychrometry apply to any physical system consisting of gasvapor mixtures. Psychrometry is a term used to describe the field of engineering concerned with the determination of physical and thermodynamic properties of gas-vapor mixtures.

Carrier psychrometric chart si units pdf