| 摘要 |
<p>A system (10) and methods of use for determining the level of a body of liquid (16) in a storage tank, irrespective of the specific gravity of that liquid. The system (10) comprises a pressure transducer (22) and an elongated tubular, flexible sheath (24). An operating liquid (26) of lower specific gravity than the body of liquid (16) is disposed within the sheath (24). The transducer (22) is also disposed within the sheath adjacent the bottom end. The sheath (24) is immersed in the body of liquid (16) so that its top end (28) is above the surface of the liquid. The pressure applied to the sheath (24) by the liquid (16) causes the sheath to collapse to a reduced internal cross sectional area. whereupon the operating liquid migrates up the sheath to form a very thin column (44). The operating liquid forming a pool (46) is located at the top of the very thin column (44). Thus the sheath expands outward adjacent the surface (16A) of the body of liquid to retain that pool. The pressure transducer provides a signal representing the pressure applied thereto by the combined height of the operating liquid column (44) and the operating liquid pool (46). This signal may be used to calculate the height of the body of liquid (16). An air vent (52) may be provided to vent the transducer to compensate for atmospheric pressure changes. <IMAGE></p> |
