MEASUREMENTS OF WATER-VAPOR CONCENTRATION DEPENDENCY OF APPARENT DIFFUSION COEFFICIENT OF FIBER ASSEMBLY USING A SIXTEEN-FOLD BEAM INFRARED HYGROMETER
We have proposed a simple method for measuring water-vapor permeability of fiber assembly using water-vapor counter diffusion in a sample between the upper moist air layer and the lower dry-air layer. Comparing the measured humidity change by optical fiber infrared hygrometer with the numerical ones the water-vapor permeability is to determine as apparent diffusion coefficient. In the present paper, a new sixteen-fold beam infrared hygrometer is developed and is installed in a new measurement apparatus to make the system more compact and to measure the water-vapor concentration change more precisely. Three types of thickness of fiber assembly (15TH-145) are tested with a new system under the condition of the moist air in the upper chamber 3, of which is changed at the dew-point of 20℃, 22.5℃, 25℃ and 27.5℃, respectively. From these measured results the apparent diffusion coefficients are estimated, respectively. These show that the water-vapor concentration dependency of apparent diffusion coefficient is also confirmed but these values are slightly low and weak dependency. Using a rough liner model of the water-vapor concentration dependency, new numerical calculations are attempted for some examples case and these results are nearly agreed with both the measured and the previous numerical ones.
Hiroshi Tanaka Kazuhiko Simoirisa
Department of Intelligent Mechanical Engineering Fukuoka Institute of Technology Fukuoka811-0295, Ja Graduate School of Intelligent Mechanical Engineering Fukuoka Institute of Technology Fukuoka811-029
国际会议
The Ninth Asian Thermophysical Properties Conference(第九届亚洲热物理性能会议 ATPC 2010)
北京
英文
605-609
2010-10-19（万方平台首次上网日期，不代表论文的发表时间）