For the return pipe our minimum pressure constraint is
Php,s - ∑ ∆Ps, j - ρs gz - ∆Phe,i - ∆Pcv,i - ∑ ∆Pr, j ≥ Px,sat + Psaf.
And at the inlet to the pump located at the heating plant, we have two constraints
Php,r ≥ PNPSH
Php,r ≥ Pa+ Pasa.
Now we have identified all of the constraints on the multiple consumermultiple
pipe solution and derived mathematical expressions for each one. In the next
chapter, we will examine a method of finding an optimal solution that satisfies all
of the constraints.