Wdn model with multiple emitter exponents

Hi,
I would like to know if anyone has implemented a pressure driven water distribution model with multiple emitter exponents (Epanet has a coefficient emitter for each node but it is possible to use only an emitter exponent). I wrote the equations system in matlab with a different emitter exponent for each node but , the system is often unbalanced and a solution is not found.(not always, probably depending on the values I give to the exponents).
Can you help me?

Daniele

We’ve successfully implemented a system with two emitters at each node using exponents of 0.5 and 1.5 respectively. This is not quite what you are doing, but our paper may be useful:

Kabaasha, A.M., Piller, O., and Van Zyl, J.E. (2018). “Incorporating the modified orifice equation into pipe network solvers for more realistic leakage modeling.” Journal of Hydraulic Engineering , 44 (2) 1-8.

Can you see a pattern of when the system becomes unstable?