Acquisition of a Fiber-Optic Distributed Temperature Sensing for Ecohydrology Education and Research

获取用于生态水文学教育和研究的光纤分布式温度传感

• 批准号: 0824829
• 负责人: Alan Rabideau
• 金额: $ 13.06万
• 依托单位: SUNY at Buffalo
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2009
• 资助国家: 美国
• 起止时间: 2009-01-01 至 2011-12-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0824829&HistoricalAwards=false
• 关键词: Acquisition; Fiber; Optic; Distributed; Temperature

0824829Becker This proposal seeks funding to acquire a fiber optic temperature sensing distributed network for hydrological research and education. The distributed temperature sensing (DTC) system acquires data by tracking the time-of-flight and backscatter from a light pulse sent through a fiber optic cable. These characteristics allow the system to calculate temperature. Different scattering mechanisms are available, but a Raman scattering device is requested. The instrument uses the ratio of anti-Stokes/Stokes backscatter to differentiate the temperature of the cable, which is known to the unknown ?outside? temperature. Two point calibrations are performed before each deployment. Understanding elemental, carbon and contaminant flow in the Great Lakes system requires a better understanding of ground-water and surface water flow regimes and interactions. Understanding non-point-source loadings to the Great Lakes requires better estimates of groundwater recharge. In addition, water use issues (like diversion for other purposes) will have unknown impacts on the Great Lakes hydrology, ecology and environment. By using DTS employments, temperature differentials can be measured as a proxy for stream recharge rates in representative basins of the Great Lakes. These measurements will be higher resolution both in terms of spatial and temporal scales relative to a gauging station approach. The PIs will also perform studies to enhance DTS technology by investigating the relationship between fiber optic cable temperature and groundwater fluid velocity. A cable buried within a permeable reactive barrier at a contaminated site will be used for this investigation. A current will be induced across the cable such that stagnant waters will offer less heat flux ? a proxy for flow. Another application for the fiber optic cable will be to assess the flow regime adjacent to and brought about by large woody debris in riverine and stream systems. Preliminary experiments using artificially-cooled water were able to delineate water masses of differing temperatures. Additionally, the cable will be moored in a ?serpentine? fashion in a near-shore region of Lake Ontario in order to study the development of thermal bars in spring and fall. Thermal bars are important for nutrient and contaminant cycling, yet are understudied in high-resolution. Finally, the cable instrument will be used for understanding wetland restoration and hydroelectric discharge studies. The instrument will be incorporated into an existing group of equipment managed and prioritized by the IGERT steering committee. It will be housed in the Department of Civil, Structural, and Environmental Engineering. Outside IGERT users will be required to pay a usage fee. Cables are fragile and require frequent replacement. Researchers using the system will be required to budget for replacement cabling. Course fees will also help offset cable replacement costs. ***

0824829 Becker该提案旨在获得用于水文研究和教育的光纤温度传感分布式网络的资金。分布式温度传感（DTC）系统通过跟踪通过光纤电缆发送的光脉冲的飞行时间和反向散射来获取数据。这些特性允许系统计算温度。不同的散射机制是可用的，但需要拉曼散射装置。该仪器利用反斯托克斯/斯托克斯反向散射的比值来区分电缆的温度，这是已知的未知？外面吗温度在每次展开前进行两点校准。要了解五大湖系统中的元素、碳和污染物流动，就需要更好地了解地下水和地表水的流动状况和相互作用。了解非点源负荷的五大湖需要更好地估计地下水补给。此外，水的使用问题（如转用于其他目的）将对五大湖的水文、生态和环境产生未知的影响。通过使用温度计，可以测量温差作为代表性的流域的五大湖流补给率的代理。这些测量在空间和时间尺度上都比测量站方法具有更高的分辨率。PI还将通过调查光纤电缆温度和地下水流速之间的关系来进行研究，以提高光纤电缆技术。将使用埋在污染场地可渗透反应屏障内的电缆进行调查。电缆上会感应出电流，这样停滞的沃茨会提供更少的热通量。一个心流的代理光纤电缆的另一个应用将是评估河流和溪流系统中大型木质碎片附近的流动状况。使用人工冷却水的初步实验能够描绘出不同温度的水团。此外，电缆将停泊在一个？蛇形？在安大略湖的近岸地区的时尚，以研究在春季和秋季热酒吧的发展。热棒是重要的养分和污染物循环，但在高分辨率的研究不足。最后，电缆仪器将用于了解湿地恢复和水电流量研究。该仪器将被纳入IGERT指导委员会管理和优先考虑的现有设备组。它将被安置在土木，结构和环境工程系。IGERT以外的用户将被要求支付使用费。电缆易碎，需要经常更换。使用该系统的研究人员将被要求为更换电缆做预算。课程费用也将有助于抵消电缆更换成本。***