Hi,
I'm working with a model which has pump model, mass exchanger model  water - water, and pressure drop model, the problem i keep receiving an error says
(ERROR: Failed to solve non-linear system using Newton solver.
To get more information: Turn on Simulation/Setup/Debug/Nonlinear solver diagnostics/Details
Solution to systems of equations not found at time = 5.62273E-008
   Nonlinear system of equations number = 16
   Infinity-norm of residue = 0.00173054
   Iteration is not making good progress.
   Accumulated number of residue calculations: 446
   Last values of solution vector:
pump.N = 0.0289816
   Last values of residual vector:
{ -0.00173054 })

Note: once i set the the pressure drop model on 0 the simulation going well,
Do have an idea about this error and how to fix it?

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