Presentation Information
[9a-E202-1]Extension to Lower Air Temperature Range in a Humidity Measurement Method Using a Heat Pipe
〇Naoya Ishiwata1, Hisashi Abe1 (1.AIST)
Keywords:
environmental test,thermoelectric module,moisture condensation
Environmental tests are used in many industries and are often conducted under high-temperature and high-humidity conditions. Humidity sensors installed in environmental-test chambers should be robust to such harsh conditions. However, those in commercial chambers have several challenges such as drift due to degradation. To tackle these challenges, a new hygrometric method based on the heat balance at the region of moisture condensation on the heat pipe has been developed. The authors previously developed a new instrument to improve some properties of the method, such as response speed. However, the applicable air temperature range of the sensor was limited to avoid condensation on the heat-pipe temperature control unit because the unit temperature falls below the ambient dew point under low air temperature conditions. In this study, we investigated the performance of the sensor under lower air temperature conditions including those around room temperature, which are also used for environmental tests. Reducing humidity around the control unit with dry-air purging enabled the expansion of the sensor’s applicable temperature range to 25 °C.