functionpowerLinearized
Power function that is linearized below a user-defined threshold
Extends from Modelica.Icons.Function (Icon for functions).
Information
Function that approximates y=xn where 0 < n so that- the function is defined and monotonically increasing for all x.
- dy/dx is bounded and continuous everywhere (for n < 1).
For x < x0, this function replaces y=xn by a linear function that is continuously differentiable everywhere.
A typical use of this function is to replace T = T4(1/4) in a radiation balance to ensure that the function is defined everywhere. This can help solving the initialization problem when a solver may be far from a solution and hence T4 < 0.
See the package Examples for the graph.
Inputs
| Type | Name | Default | Description |
|---|---|---|---|
| Real | x | Abscissa value | |
| Real | n | Exponent | |
| Real | x0 | Abscissa value below which linearization occurs |
Outputs
| Type | Name | Default | Description |
|---|---|---|---|
| Real | y | Function value |
Revisions
-
February 3, 2011, by Michael Wetter:
First implementation.