Humidification of high and low temperature humidity chamber

High and low temperature humidity test chamber is able to achieve humidity control function through the humidification and dehumidification,The following introduction is currently used in the high and low temperature test chamber:

At the beginning, the humidification method is to spray water to the wall of the high and low temperature test chamber, and the saturated pressure of the water surface is controlled by controlling the water temperature. The water on the surface of the chamber wall forms a larger surface, in which the relative humidity in the test chamber is increased by adding water vapor pressure to the chamber by diffusion. This method appeared in the early 1950s. Because the control of humidity at that time was mainly based on the simple switch quantity adjustment of mercury electric contact guide meter, the control adaptability of water temperature of large lag hot water tank was poor, so the transition process of control was longer. More importantly, when spraying the wall, water droplets inevitably pollute the sample to varying degrees. At the same time, there are certain requirements for drainage in the climatic chamber.

But this method still has some advantages. Although its control transition process is longer, the humidity fluctuation is small after the system is stable, so it is more suitable to do constant humid heat test. In addition, water vapor does not increase the extra heat in the system during humidification. Also, when the spray water temperature is controlled below the test point temperature, the spray water is dehumidified

This method was quickly replaced by steam humidification and shallow water disc humidification, both are the most commonly used humidification method for temperature humidity test chamber today.