| 摘要 |
Detection of leaks and hydraulic characteristics in a section of oil pipeline involves sealing the section at each end, and measuring the oil temperature profile using temperature sensors linked to a control center by a fibre optic cable. The profile is evaluated using a heat transport model, which takes the pipe's local position and arrangement into account. Prior to the leak detection process, calibration measurements are made to profile the surrender of heat from the pipe, and the local geological conditions. The calibration is repeated at different seasons and/or under different weather conditions. The temperatures measured are used as pump parameters. A dynamic heat transport model is used which employs variables including local geology and current weather conditions. A leak is detected by balancing the quantities of incoming and outgoing oil, in conjunction with the oil temperature profile along the pipe. The process excludes errors arising from a switch to a supply of different temperature from a different tank or batch. In the model, the oil temperature profile transverse to the direction of flow is a constant, and the temperature gradient in the plane transverse to the direction of flow is assumed to be much greater the axial direction. The process complements information derived from prior art real- time simulation of hydraulic pipeline systems.
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