.Buildings.Fluid.Actuators.BaseClasses.der_equalPercentage

Information

This function computes the derivative of the opening characteristics of an equal percentage valve.

The function is the derivative of Buildings.Fluid.Actuators.BaseClasses.equalPercentage.

Interface

function der_equalPercentage
  extends Modelica.Icons.Function;
  input Real y "Valve opening signal, y=1 is fully open";
  input Real R "Rangeability, R=50...100 typically";
  input Real l(min = 0, max = 1) "Valve leakage, l=Kv(y=0)/Kv(y=1)";
  input Real delta "Range of significant deviation from equal percentage law";
  input Real der_y "Derivative of valve opening signal";
  output Real der_phi "Derivative of ratio actual to nominal mass flow rate, dphi/dy";
end der_equalPercentage;

Revisions

• March 30, 2011 by Michael Wetter:
  Removed inputs for which no derivative is implemented from the argument list, and added zeroDerivative keyword in function that calls this function.
• February 4, 2010 by Michael Wetter:
  Fixed implementation of derivative function.
• June 6, 2008 by Michael Wetter:
  First implementation.