functionbasicFlowFunction_m_flow_der

1st derivative of function that computes pressure drop for given mass flow rate

Extends from Modelica.Icons.Function (Icon for functions).

Information

Function that implements the first order derivative of Buildings.Fluid.BaseClasses.FlowModels.basicFlowFunction_m_flow, assuming a constant flow coefficient.

When called with m_flow_der=der(m_flow), this function returns the time derivative of dp. When called with m_flow_der=1, this function returns the derivative of dp with respect to m_flow.

Inputs

TypeNameDefaultDescription
Modelica.Units.SI.MassFlowRatem_flowMass flow rate in design flow direction
RealkFlow coefficient, k=m_flow/sqrt(dp), with unit=(kg.m)^(1/2)
Modelica.Units.SI.MassFlowRatem_flow_turbulentMass flow rate where transition to turbulent flow occurs
Realm_flow_derDerivative of mass flow rate in design flow direction

Outputs

TypeNameDefaultDescription
Realdp_derDerivative of pressure difference between port_a and port_b (= port_a.p - port_b.p)

Revisions

  • January 4, 2019, by Michael Wetter:
    Set `Inline=false`.
    See #1070.
  • May 1, 2017, by Filip Jorissen:
    Revised implementation such that Buildings.Fluid.BaseClasses.FlowModels.basicFlowFunction_m_flow is C2 continuous. See #725.
  • July 29, 2015, by Michael Wetter:
    First implementation to avoid in Dymola 2016 the warning "Differentiating ... under the assumption that it is continuous at switching".