Abstract: A sensitivity testing device and method calibrates the distributed optic-fiber temperature sensing (DOFTS) system for inflow and infiltration (I/I) identification in drainage pipeline. A temperature-adjustable water supply tank is provided with a heating rod and a high-accuracy physical water temperature sensor and is electrically connected with a centralized programmable logic controller (PLC) system; the temperature-adjustable water supply tank is connected with a water inlet of a water pump through a first connecting pipe; a water outlet of the water pump is communicated with a water inlet of an experimental pipeline through a second connecting pipe; and a water outlet of the experimental pipeline is communicated with the temperature-adjustable water supply tank through a third connecting pipe.

Abstract: A sewer pipe inflow and infiltration diagnosis method based on a distributed fiber-optic temperature measurement system is provided. The inflow and infiltration diagnosis method includes the following steps: S1: transmitting, by an optical time-domain reflectometer, an original optical signal to a temperature sensing fiber-optic cable provided in a sewer pipe; S2: feeding back, by the temperature sensing fiber-optic cable, a modulated optical signal to the optical time-domain reflectometer due to a temperature effect; S3: subjecting the modulated optical signal to photoelectric conversion, so as to acquire binary information; S4: converting the binary information into decimal information; S5: drawing a spatiotemporal map of a water temperature; and S6: eliminating a background noise value, identifying an abnormal water temperature point, determining an inflow and infiltration point of the sewer pipe, and determining an abnormal inflow and infiltration point of the sewer pipe.

Abstract: A sewer pipe inflow and infiltration diagnosis method based on a distributed fiber-optic temperature measurement system is provided. The inflow and infiltration diagnosis method includes the following steps: S1: transmitting, by an optical time-domain reflectometer, an original optical signal to a temperature sensing fiber-optic cable provided in a sewer pipe; S2: feeding back, by the temperature sensing fiber-optic cable, a modulated optical signal to the optical time-domain reflectometer due to a temperature effect; S3: subjecting the modulated optical signal to photoelectric conversion, so as to acquire binary information; S4: converting the binary information into decimal information; S5: drawing a spatiotemporal map of a water temperature; and S6: eliminating a background noise value, identifying an abnormal water temperature point, determining an inflow and infiltration point of the sewer pipe, and determining an abnormal inflow and infiltration point of the sewer pipe.

Abstract: A grid-based source-tracing method and system for sewage outfalls and a storage medium are provided. The method specifically includes the steps of: dividing a river into multiple reaches; determining monitoring sites according to the divided reaches; acquiring on-line monitoring data of each of the monitoring sites, and calculating soft measurement data; determining a river reach with sewage outfalls according to upstream and downstream soft measurement data; and intensively arranging monitoring sites in the river reach with sewage outfalls to subdivide the river reach with sewage outfalls, thereby determining a position of a sewage outfall. The method divides the river into multiple reaches and performs the grid-based source-tracing for the sewage outfall of the river gradually. In real practice, with online conductivity and water level monitoring data, the method can effectively determine the river reach with sewage outfalls using soft measurement.