Dry and wet bulb structure

Dry wet bulb, is a kind of measuring the temperature and absolute humidity instrument. There are two same dry wet bulb thermometer, one of the inductive part doesn't pack gauze, dry bulb thermometer, it shows the air temperature; Induction part of another package with icy gauze soaked with water or have, according to wet bulb, because of the wet gauze ball evaporation heat, the former shows the degrees in unsaturated air is always higher than the latter. From the difference of the two with specialized meteorological tables found to absolute humidity. Psychrometer in free air circulation within the screen, or by artificial ventilation methods make the air flow freely, the latter such as ventilation dry wet bulb or call assmann ventilation psychrometer and hand dry wet bulb, of the psychrometer is often used in the field work. The size of the dry wet bulb difference, mainly related to the air humidity. The smaller the humidity, moisture evaporates faster on the surface of the wet ball, wet bulb temperature drop, the more the greater the dry wet bulb temperature difference; On the other hand, the humidity is big, wet ball slow evaporation, wet bulb temperature decrease less, dry wet bulb temperature difference is small. Dry wet bulb temperature table, of course, the size of the difference also with other factors, such as wet ball near the ventilation velocity, pressure, wet ball size, and the wet way.