Holistic Diagnosis of Pipeline System with Impedance Method

Abstract

In this study, a diagnosis potential of impedance method implementing several unsteady friction models for a pipeline system with or without leakage. The development based on impedance approach provides a feasible and flexible modelling environment that can address not only for various fundamental system properties, but also for dynamic variables in transient generation. Calibration parameters cover conventional diagnostic parameters such as friction parameters and leakage, steady and transient condition parameters such as the initial flow rate and valve closure duration, and system characteristics such as pipeline length and wave propagation speed. Based on the perspective of the impedance for system definition, corresponding response functions in the frequency domain approach were derived. Time domain responses of pipeline systems were integrated into the genetic algorithm for inverse transient analysis. Unsteady models addressed both frequency-dependent friction and acceleration-based frictions. Parameter calibrations with experimental data have shown that the impedance-based approach provides a versatile and feasible optimization structure via the objective fitting function of the pressure head variation. The performance of the integrated optimization examples demonstrates the robustness of the impedance-based approach for a representation of a real-life system, a diagnosis of system abnormality and a configuration of system characteristics.