Fuzzy logic for discharge coefficient interpolation in hydraulic transients: experimental analysis

ABSTRACT

Understanding hydraulic transients in real sanitation systems is extremely important, especially when developing expansion and/or adequacy projects in facilities that operate in a transitory regime. The aim of this study is to propose a discharge coefficient (C_d) interpolation model to calibrate hydraulic transients in a pipeline operating in a non-permanent regime (transitory). The proposed methodology comprised the following steps: (1) theoretical foundation; (2) experimental module; (3) discharge coefficient interpolation model called Fuzzy-C_d and (4) calibration and verification. The Fuzzy-C_d model presented the mean absolute percentage error (MAPE) of 26.5% while the Basic Water-hammer Program (BWP) error was 32.8%. The results indicated that the Fuzzy-C_d model presents, in general, advances in relation to the conventional model, especially at moments of non-linear evolution of pressure values during the hydraulic transient.

KEYWORDS:

• Fuzzy sets
• water hammer
• service lines
• uncertainties

Acknowledgments

The authors would like to thank Nobres Water Supplier and Sanitation Company (ESAN – Empresa de Saneamento de Nobres Ltda) for the help/partnership in making the experimental module.

Disclosure Statement

No potential conflict of interest was reported by the authors.