Optimal Pressure Management in Water Distribution Systems Using an Accurate Pressure Reducing Valve Model Based Complementarity Constraints

Abstract

Water loss according to water leakages in water distribution systems (WDSs) is a challenging problem worldwide. An inappropriate operation of the WDS leads to unnecessarily high pressure distribution in the WDS and thus a large amount of water leakage exists. For this reason, optimal pressure management in WDSs through regulating operations of pressure reducing valves (PRVs) is priority for water utilities. The pressure management can be accomplished in a hierarchical control scheme with high level and low level controllers. While the high level controller is responsible for calculating pressure set points for critical nodes, the task of a low level controller is to regulate the pressures at the critical nodes to the set points. The optimal pressure management in the high level controller can be casted into a nonlinear programing problem (NLP) where PRV models are crucial and determine proper operation of the WDS and quality of overall pressure control. PRV models having been used until now either describe two operating modes (active and open modes) or three operating modes (active, open and check valve modes) with parameter dependence. Such models make the formulated NLP unsuitable for the case PRVs work in check valve modes or resulted in inaccurate NLP solution with unexpected operation modes of PRVs, respectively. Therefore, this paper proposes an accurate PRV model based on complementarity constraints. The new PRV model is parameter-less dependence and is capable of describing complete operation modes of PRVs in practice. As a result, the formulated NLP is general and provides accurate NLP solution. The efficiency of our new PRV model is demonstrated on numerous case studies for optimal pressure management of WDSs.

Modeling and optimization of pressure and water age for evaluation of urban water distribution systems performance

“…This means that the distribution system could experiences bursts and leakages in the area with high pressure ( Awe et al., 2020 ). This high water losses can cause service interruptions, energy losses, and pollutant ingress ( Dai, 2021 ). Here, pressure reducing valves and zoning are very important to minimize such problems.…”

“…There are two types of water losses in water distribution systems (WDSs): real and apparent losses. Leaks at network fittings, pipe joints, breaks and/or bursts in pipes are the main causes of real losses, whereas apparent losses are caused by inaccurate meters and/or unauthorized consumption ( Dai, 2021 ; Lambert A.O., 2002 ; Puust et al., 2010 ). Due to low or even negative pressure situations, high water losses can cause service interruptions, energy losses, and pollutant ingress ( AL-Washali et al., 2020 ; Dai, 2021 ; Kouchi et al., 2017 ).…”

“…Leaks at network fittings, pipe joints, breaks and/or bursts in pipes are the main causes of real losses, whereas apparent losses are caused by inaccurate meters and/or unauthorized consumption ( Dai, 2021 ; Lambert A.O., 2002 ; Puust et al., 2010 ). Due to low or even negative pressure situations, high water losses can cause service interruptions, energy losses, and pollutant ingress ( AL-Washali et al., 2020 ; Dai, 2021 ; Kouchi et al., 2017 ). With increased retention time in the water distribution system, water quality will decline, resulting in problems such as disinfection by-product generation, disinfectant decay, corrosion, taste, and odor ( Cheng et al., 2015 ).…”

Modeling and Control of Pipeline Networks Supplied by Automated Irrigation Channels

“…Nonlinear models for the control of pipeline networks are presented in Kaltenbacher et al (2017Kaltenbacher et al ( , 2018; De Persis and Kallesoe (2011). Control strategies for regulating hydraulic networks using pressure reducing valves are presented in Prescott and Ulanicki (2008); Bermúdez et al (2021a); Dai (2021); Galuppini et al (2020); Bermúdez et al (2021b). Flow control of fluid in pipelines using torsional actuator placed on a motor pump is presented in Razvarz et al (2020).…”

Appraising the Impact of Pressure Control on Leakage Flow in Water Distribution Networks

“…However, the type of the PRVs and the control strategy to be used may need to be carefully selected, given that the laboratory tests in [15] showed some pressure oscillation when using the piston-actuated PRVs. Furthermore, it was shown in [16] that model formulation of the said PRVs bears relevance in the solution of the nonlinear programming (NLP) formulated for pressure control.…”