Developpement d’un generateur d’air humide a dilution

Abstract

Abstract. Since more than 20 years the hygrometry laboratory at LNE-CETIAT developed its own calibration facility in order to improve the French national reference in humidity. Facilities are mainly based on humid air generator providing, to hygrometers to be calibrated, humid gas, metrologically controlled. These calibration benches worked with air at atmospheric pressure according to a closed loop circulation. This may lead to some limitation in terms of calibration conditions such as type of gas, working pressure, pressure drop, or time duration for reaching equilibrium state prior to calibration. The LNE-CETIAT started the development of a humid air generator based on dilution principle generation. The aim is to realize a mixture of dry gas and a humid gas by controlling the flow of each type of gas. Thus the final moist air generated is function of each flow, the amount of moisture of the humid gas and the working pressure. This work present the characterization with the very first results obtained with this generator obtained in these working conditions.