- freely available
Appl. Sci. 2017, 7(1), 2; doi:10.3390/app7010002
2. Unburied Pipe Tests
2.1. Experimental Setup and Tests
- The non-leaking state (referred to as NL), set by stopping all the leaks with the repair clamps;
- Water leaking from the j-th active leak (Lk-j), a condition set by temporarily removing the corresponding repair clamp (Figure 2a);
- All the leaks activated simultaneously (Lk-123).
- Total amount of Hits per acquisition, which coincide with the number of AE events for the adopted setup, where only one sensor is installed for measurements;
- Cumulative Counts, computed by summing the Counts of all Hits related to one acquisition;
- Cumulative Amplitude, computed by adding together the Amplitude values of all Hits related to one acquisition.
2.2. Results and Discussion
3. Buried Pipe Tests
3.1. Experimental Setup and Tests
- acquisitions in non-leaking state (referred to as NLb hereafter), set by deactivating all the leaks with the repair clamps, to assess the environmental noise;
- water leaking against backfill soil from the j-th active leak (Lk-jb), a condition set by temporarily removing the corresponding repair clamp (Figure 8b).
- trend of three AE parameters, namely Hits, Cumulative Counts, and Cumulative Amplitude;
- distribution of AE events in an AF versus RA value diagram.
3.2. Results and Discussion
Conflicts of Interest
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|Leak (Buried Pipe)||Distance (m)||Flow Rate (L/h)|
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