This model is similar to Buildings.Fluid.FixedResistances.HydraulicDiameter except for the modifications below which allow to use this model for computing the hydraulic diameter at initialization, based on the pressure drop per pipe length at nominal flow rate.
v_nominal is computed based on the nominal flow rate.
dp_nominal = fac*dpStraightPipe_nominal is
solved at initialization for the hydraulic diameter dh.
dp_nominal is assigned a value that does not need
to be computed at initialization.
This is required per Modelica specification because
the structural parameter computeFlowResistance
depends on dp_nominal and must be evaluated at compile time.
start attribute for parameter dh changed to 0.01.min attribute for parameter dh changed to 0.001.