| 摘要 |
<P>PROBLEM TO BE SOLVED: To precisely measure the hydrogen concentration (nitrogen concentration) in a three-component gas mixture comprising water vapor, hydrogen, and nitrogen, using an ultrasonic wave gas concentration meter. <P>SOLUTION: An enlarged part 9 having a larger internal diameter is formed at the upstream side of a sound wave measuring tube 1. Water is stored at the bottom of the enlarged part 9 to keep a sound velocity measuring section at a saturated vapor state through the evaporation of the stored water. Regarding that a gas to be measured is in a saturated vapor state, the concentration of water vapor is calculated from a temperature measured by a temperature measuring instrument 30 and a pressure measured by a pressure gage 52, and the concentration of hydrogen (concentration of nitrogen) is determined on the basis of a sound velocity C measured using ultrasonic wave receiver/transmitter 4a, 4b. <P>COPYRIGHT: (C)2005,JPO&NCIPI |
