How to measure Wet-bulb temperature in Cooling Tower Process

Most engineers measure wet bulb temperature with the help of sling psychrometer. The wet bulb

temperature is measured by causing air to move across a thermometer whose bulb is encased in a wetted muslin cloth, As the air moves across the wetted bulb, moisture is evaporated and sensible heat is transferred to the wick, cooling the mercury and causing equilibrium to be reached at the wet-bulb temperature.

For perfect result, the velocity of the air across the wick must be approx 1000 fpm. And, the water used to wet the wick should be as close as possible to the wet-bulb temperature. Engineers recommend distilled water for wetting of the wick. 

For detailed information and updates on cooling tower industry, contact engineers at CASE.