School of Civil Engineering, Dalian University of Technology, Dalian 116024, China.
Sensors (Basel). 2013 Jan 24;13(2):1490-509. doi: 10.3390/s130201490.
A scour monitoring system for subsea pipeline based on active thermometry is proposed in this paper. The temperature reading of the proposed system is based on a distributed Brillouin optical fiber sensing technique. A thermal cable acts as the main component of the system, which consists of a heating belt, armored optical fibers and heat-shrinkable tubes which run parallel to the pipeline. The scour-induced free span can be monitored through different heat transfer behaviors of in-water and in-sediment scenarios during heating and cooling processes. Two sets of experiments, including exposing different lengths of the upper surface of the pipeline to water and creating free spans of various lengths, were carried out in laboratory. In both cases, the scour condition was immediately detected by the proposed monitoring system, which confirmed the system is robust and very sensitive. Numerical study of the method was also investigated by using the finite element method (FEM) with ANSYS, resulting in reasonable agreement with the test data. This brand new system provides a promising, low cost, highly precise and flexible approach for scour monitoring of subsea pipelines.
本文提出了一种基于主动测温法的海底管道冲刷监测系统。该系统的温度读数基于分布式布里渊光纤传感技术。热缆作为系统的主要组成部分，由加热带、铠装光纤和与管道平行的热缩管组成。通过在加热和冷却过程中，不同的水内和泥沙内传热行为，可以监测冲刷引起的自由跨度。在实验室中进行了两组实验，包括暴露管道上表面的不同长度到水中和创建不同长度的自由跨度。在这两种情况下，冲刷状态都被所提出的监测系统立即检测到，这证实了系统是坚固且非常敏感的。还通过使用 ANSYS 的有限元法 (FEM) 对该方法进行了数值研究，结果与测试数据吻合较好。这种全新的系统为海底管道的冲刷监测提供了一种有前途的、低成本、高精度和灵活的方法。
