finally, as depicted in Fig. la, when we consider pumps with fixed-speed drives, for each discharge pressure, we are allowed to pump only one given flow. Thus, we can write that,
where p„ is the head characteristic of the pump พ, well-approximated by a quadratic function of q5j)P„, and M is an upper threshold on Pjj.
Our modeling leads to a mixed-integer quadratic constrained program, encoded using Python language and the Gurobi solver [7], While the time of resolution is acceptable for small networks, it is too long for the real-time instrumentation of a large network, typically a pumping station with 6 pumps and 20 water towers. With the aim of reducing the time of resolution, the full paper will present a heuristic based on a continuation method.