Measuring the relative humidity of dry kiln air above 100°C

摘要: Normal measurement techniques for determining the relative humidity of air cannot be used all high temperature and conditions. For additional requirements such as reliability, low maintenance simple operation hardly any suitable instruments exist. The principle method described here is to branch-off a small stream from sampling point cool it boiling water. A commercial psychrometer made below 100°C then measure dry- wet-bulb cooled air, i.e. partial vapour pressure branched-off measured. In addition, dry bulb also measured thus enabling calculation its humidity.