The pressure drop across the inlet and outlet connectors is computed according to a turbulent friction model, i.e. is proportional to the squared velocity of the fluid. The friction coefficient can be specified directly, or by giving an operating point, or as a multiple of the kinetic pressure. In the latter two cases, the correction coefficient Kfc can be used to modify the friction coefficient, e.g. to fit some experimental operating point.

A small linear pressure drop is added to avoid numerical singularities at low or zero flowrate. The wnom parameter must be always specified; the additional linear pressure drop is such that it is equal to the turbulent pressure drop when the flowrate is equal to wnf*wnom (the default value is 1% of the nominal flowrate).

Modelling options

The following options are available to specify the friction coefficient:


Name Description


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