| 摘要 |
PURPOSE:To detect even a small amount of leakage by estimating the pressure at a certain point from pressures at measurement points upstream and downstream it and detecting a leakage from the estimated value and the actual measured value. CONSTITUTION:The liquid pressure is measured for a small sampling time or continuously at measurement points of a fluid transferring pipeline 1 and sent from pressure transmitters 4 to a computer 9. The pressure at a certain measurement point P0 at time (t) when no leakage is present is calculated from the measured value at a measurement point P1 upstream and apart from the point P0 by DELTAx1 at t-DELTAx1/a and the measured value at a measurement point P2 downstream and apart from the point P0 by DELTAx2 at t-DELTAx2/a to determine the estimated value, where (a) is the speed of sound in the pipeline 1. A leakage can be detected by comparing the estimated value with the actual measured value at the point P0 at time (t). |
