Buildings.Fluid.Utilities

Package Content

Name	Description
EfficiencyCurves	Package with functions for efficiency curves
extendedPolynomial	Polynomial that is linearly extended at user specified values
polynomial	Polynomial, used because OpenModelica 1.4.3 does not expand the sum() into a scalar
Examples	Collection of models that illustrate model use and test models
BaseClasses	Library with base classes for utility functions

Buildings.Fluid.Utilities.extendedPolynomial

Information

y = ∑_i=1ⁿ c_i x^i-1

Extends from Modelica.Icons.Function (Icon for a function).

Inputs

Type	Name	Default	Description
Real	c[:]		Polynomial coefficients
Real	x		x value
Real	xMin		Minimum x value for polynomial
Real	xMax		Maximum x value for polynomial

Outputs

Type	Name	Description
Real	y	y value

Modelica definition

function extendedPolynomial 
  "Polynomial that is linearly extended at user specified values"
  annotation(derivative=BaseClasses.der_extendedPolynomial);
  extends Modelica.Icons.Function;
  input Real[:] c "Polynomial coefficients";
  input Real x "x value";
  input Real xMin "Minimum x value for polynomial";
  input Real xMax "Maximum x value for polynomial";
  output Real y "y value";
protected 
 Integer N = size(c,1) "Number of coefficients";
algorithm 
if x < xMin then
   y := c[1];
   for i in 2:N loop
     y := y + xMin^(i - 1)*c[i] + (x - xMin)*(i - 1)*xMin^(i - 2)*c[i];
   end for;
  elseif x < xMax then
   y := c[1];
   for i in 2:N loop
     y := y + x^(i - 1)*c[i];
  end for;
  else
     y := c[1];
     for i in 2:N loop
       y := y + xMax^(i - 1)*c[i] + (x - xMax)*(i - 1)*xMax^(i - 2)*c[i];
    end for;
  end if;
end extendedPolynomial;

Buildings.Fluid.Utilities.polynomial

Information

Function that computes

y = ∑_i=1ⁿ c_i x^i-1

Extends from Modelica.Icons.Function (Icon for a function).

Inputs

Type	Name	Default	Description
Real	c[:]		Coefficients
Real	x		Independent variable

Outputs

Type	Name	Description
Real	y	Dependent variable

Modelica definition

function polynomial 
  "Polynomial, used because OpenModelica 1.4.3 does not expand the sum() into a scalar"
  extends Modelica.Icons.Function;
  input Real[:] c "Coefficients";
  input Real x "Independent variable";
  output Real y "Dependent variable";
algorithm 
 y := c[1];
 for i in 2 : size(c,1) loop
   y := y + x^(i-1) * c[i];
 end for;
end polynomial;