| 摘要 |
An electromagnetic flow meter apparatus (1) for measuring flow rate of a fluid passing therethrough comprises a conduit (3), an insert (5) for positioning within the conduit which defines a fluid inklet (7), a fluid outlet (9) and a measuring section (10). The flow meter insert also comprises a single coil (17) for generating a magnetic field across the measuring section and electrodes (14) for detecting induced electrical potential due to the fluid passage. The flow meter insert also includes restriction means for conditioning the flow through the measuring section. The combination of the single coil and the flow restriction means provides a flow meter with a desired level of accuracy. In a further embodiment the single coil and the electrodes are arranged so that the integral of a weight function, which defines the sensitivity of the flow meter to fluid velocity through different parts of the measuring section, over the first half of a measuring section closest to the coil is between 0.4 and 1.3 times the integral of the weight function over the other half of the measuring section. |
