| 摘要 |
<p>A gas flow correction sensor for producing an output signal proportional to the ratio between line pressure and line temperature for gas flowing in a line (10), for use in correcting the output of a volumetric flow meter connected in the line (10), comprises a sealed chamber (14) containing a fixed mass of a reference gas. The sealed chamber (14) includes a bellows portion (15) subjected to line pressure, thus maintaining the reference gas at line pressure. Additionally, the sealed chamber (14) is thermally insulated and includes at least a portion disposed in a thermowell immersed in the line (10), so as to maintain the reference gas at line temperature. A vibrating quartz density sensor (101) is also mounted in the thermowell, so as to produce an output signal whose frequency is proportional to the density of the reference gas, which can be shown also to be proportional to the desired line pressure to line temperature ratio.</p> |
