Improvement of CETIAT humidity generator for dew/frost-point in a range from - 80 °C up to + 15 °C

Résumé et principaux résultats

Article présenté au 4° congrès mondial d'Hygrométrie ISHM à Taipei (Taiwan), en 16-19 septembre 2002

The humid air generator designed by CETIAT for the range between - 80 °C and + 15 °C has been upgraded. The design of the generator is based on the definition of the dew-point temperature, the chamber acting as a closed system containing water and moist air in equilibrium. The reference temperature is measured by a Pt25 ohms, leading to temperature measurement uncertainties less than 4 mK (in term of one standard uncertainty). At the same time, analysing the system in transient regime shows influence of frost formation on homogeneity. Reduction of uncertainties on temperature measurement and homogeneity leads us to be able to separate several components of the uncertainties, thus increasing the knowledge of the generator.

Thème

Méthodes et matériels de mesure

Mots-clés

Etalonnage, Mesure, Mesure d'humidité des gaz

Auteurs

BLANQUART Bertrand, CRETINON Bernard