Model for an air damper whose airflow is proportional to the input signal, assuming
that at y = 1, m_flow = m_flow_nominal. This is unless the pressure difference
dp is too low,
in which case a kDam = m_flow_nominal/sqrt(dp_nominal) characteristic is used.
The model is similar to IBPSA.Fluid.Actuators.Valves.TwoWayPressureIndependent, except for adaptations for damper parameters. Please see that documentation for more information.