functionpower
Flow vs. electrical power characteristics for fan or pump
Extends from Modelica.Icons.Function (Icon for functions).
Information
This function computes the fan power consumption for given volume flow rate, speed and performance data. The power consumption is
P = rN3 s(V̇/rN, d),
where P is the power consumption, rN is the normalized fan speed, V̇ is the volume flow rate and d are performance data for fan or pump power consumption at rN=1.
Implementation
The function s(·, ·) is a cubic hermite spline. If the data d define a monotone decreasing sequence, then s(·, d) is a monotone decreasing function.
Inputs
| Type | Name | Default | Description |
|---|---|---|---|
| Buildings.Fluid.Movers.BaseClasses.Characteristics.powerParameters | per | Pressure performance data | |
| Modelica.Units.SI.VolumeFlowRate | V_flow | Volumetric flow rate | |
| Real | r_N | Relative speed | |
| Real[:] | d | Derivatives at support points for spline interpolation | |
| Real | delta | Small value for switching implementation around zero speed |
Outputs
| Type | Name | Default | Description |
|---|---|---|---|
| Modelica.Units.SI.Power | P | Power consumption |
Revisions
-
February 26, 2014, by Filip Jorissen:
Changed polynomial to be evaluated atV_flow/r_Ninstead ofV_flowto properly account for the scaling law. See #202 for a discussion and validation. -
September 28, 2011, by Michael Wetter:
First implementation.