| 摘要 |
PURPOSE:To improve isothermal property in sampling gas by sealably containing an evaporable and condensable fluid into a closed hollow chamber outside a sampling tube extending from a gas sampling port to the outer wall of a gas passage surrounding the tube. CONSTITUTION:A closed hollow chamber 8 is provided outside a sampling tube 4 from near a gas sampling port 5 to near the outer wall of a gas passage 1 and an evaporable and condensable fluid 10 is sealed thereinto 8. The fluid 10 evaporates in the hollow chamber 8 heated by a high temperature gas to be measured, moving upward and condensed at an upper part of the chamber 8 radiating heat. The fluid 10 returned to liquid lowers by a gravity and through a capillary path 9 provided in the hollow chamber 8 due to capillary phenomenon. Such a phenomenon makes the inside of the hollow chamber 8 to be maintained at an almost even temperature equal to that of the gas being measured. The hollow chamber 8 of the sampling tube 4 is maintained at a very even temperature by heat of the gas being measured surrounding it. |
