A New Method on Measuring Moisture Content in Gas

A new method on measuring moisture content in gas with high accuracy is presented. Fibreglass is filled in a filter tube fixed in the sampling pipe. Mist of gas will be intercepted by the fibreglass when the gas flows through the sampling tube filled with fibreglass. Moisture content in gas can be calculated on condition that volume of gas flowing through the sampling pipe at unit time is measured. Collected efficiency increases with fibreglass filling ratio, filling thickness and single fibre collected efficiency while decreases with fibre diameter. Collected efficiency should be more than 99% if suitable diameter fibreglass is selected. The cooling time in the exsiccator must be more than 20 minutes. Purity of the fibreglass has great influence on its stability. For the fibreglass with a purity of 99.5%, Weight loss is 0.1 mg for seven hours in the oven. It can be seen from the comparison experiment of filter method, absorption method and LDV method. Fibreglass filter method has high accuracy, good repeatability and stability. The measuring results are not affected by ambient and gas temperature.