抄録
A simple method is required for measuring humidity in a wide range of conditions from room air to superheated steam for several hours. In this study, we applied the theory of a psychrometer to develop a humidity monitoring system by using cylindrical porous ceramic media as a sensing element. This system contains a section for supplying/discharging water. We tested the performance of this system in terms of its measurement accuracy and response time. At a gas flow rate of 1 m/s and a gas temperature less than 310℃, the error of the steam mole fraction was observed to be less than 10%. In addition, a response time was reduced as a sensing element diameter was smaller. The system had a 90% response time of less than 60 s at a gas temperature of 200℃, a gas flow rate of 1 m/s, a flow rate of supplied water of 0.01 g/s and a water temperature of 25℃ when a sensing element diameter was 9mm.
