Sling psychrometer

Definition

A thermometer wrapped in a water-soaked cloth and spun through the air to maximize evaporation, used to measure wet-bulb temperature.

Spinning the wetted thermometer drives evaporation from the cloth, cooling the bulb until it reads the wet-bulb temperature. The reading reflects the air’s remaining evaporative cooling potential. It is the field instrument behind tower approach and capacity assessments.

Related concepts

Approach (cooling tower) · Wet-bulb temperature · Dry-bulb temperature

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Part of The Blueprint of Water · 📏 measurement