| 摘要 |
<p>The method involves using temperature sensors, which consist of fibre optical cables, installed as continuous loops in vertical (6) and horizontal (7) holes drilled into a dam, dyke or reservoir. This enables leak detection from the changes in the temperature in the region around the leak. The cables are fitted into vertical hydraulic pipes (12) or hoses, and in pipes fitted into horizontal ducts. The ratio of the horizontal to vertical lengths of the cable is preferably between 1 and 10. To allow a larger bend radius for the optical fibres the ends of the vertical holes, typically 15 to 150 mm in diameter, are enlarged to a greater diameter.</p> |
