How much do you know dry wet bulb?

Dry wet bulb in areas such as education institutions use more, but there is a question that many people in the use of principle of what it is? Today instrument will give you specific introduction of dry wet bulb, said its structure: first dry wet bulb is a kind of measuring temperature, gas wet a device. It is composed of two same ordinary thermometer, a used to measure temperature, dry bulb thermometer, the other in ball encase with distilled water wet gauze, gauze bottom into distilled water, according to wet bulb. Then what is the principle of it? Two dry foam glass bulb thermometer thermometer exposed to air, shows the air temperature or room temperature: soaked the glass bulb of the thermometer was wet cloth, because evaporation heat water in wet cloth, so wet thermometer readings than dry dip thermometer readings. And on the same day the air is dry, the faster evaporation, heat, the more the greater the difference of the two thermometer readings; On the contrary, the more water vapor in the air of the humidity, the greater the evaporation. The smaller the two thermometer readings of the poor, so the two thermometer readings can response the content of water vapor in the air. At this point, the temperature difference between wet and dry ball and environment relative humidity has a corresponding relationship, but the relationship is nonlinear. Expressed in formula is quite complicated. （ Note: due to the dry wet bulb is the method of indirect measurement of humidity, its equation using the conditions to meet: wet winds reach 2 near the ball. More than 5 m/s. ） According to the dry bulb temperature and wet bulb temperature is measured, check & other; Wet air chart & throughout; , it is known that the state of air temperature, humidity, specific heat, enthalpy, specific volume, water vapor partial pressure, heat, sensible heat and latent heat, etc. The wet air through measured values, the comparison chart can calculate air heating, cooling, humidifying and dehumidifying state changes. Is it for dry wet bulb has a new understanding?