modelEulerReducedSpeed

Validates the Euler number method at reduced mover speed

Extends from Modelica.Icons.Example (Icon for runnable examples).

Information

Similar to Buildings.Fluid.Movers.BaseClasses.Validation.EulerComparison, this model compares the power computed from the Euler number method with measured values. The power data at speeds N=4100, 3400, and 2500 RPM from the power map of Buildings.Fluid.Movers.Data.Fans.Greenheck.BIDW13 (shown below) was used. Note that the pressure curves in the figure do not seem to be independently measured but rather simply scaled from the nominal curve. However, because the Euler number method also does not account for the efficiency degradation along any curve Δp=kV̇2, using the Euler number method has equivalent accuracy to using such power maps.

image

Parameters

TypeNameDefaultDescription
IntegernOrisize(per1.power.V_flow, 1)Number of data points for pressure curve
Modelica.Units.SI.DensityrhoCon1.2Constant density
Buildings.Fluid.Movers.Data.Fans.Greenheck.BIDW13per1Mover performance curves with flow rate, pressure rise, and power
Buildings.Fluid.Movers.Data.Genericper2Mover performance curves at reduced speed N=3400
Buildings.Fluid.Movers.Data.Genericper3Mover performance curves at reduced speed N=2500

Components

TypeNameDefaultDescription
Modelica.Units.SI.Powerpow1Buildings.Utilities.Math.Functions.smoothInterpolation(x = m1_flow.y/rhoCon, xSup = per1.power.V_flow, ySup = per1.power.P, ensureMonotonicity = false)Measured power
Modelica.Units.SI.Powerpow2Buildings.Utilities.Math.Functions.smoothInterpolation(x = m2_flow.y/rhoCon, xSup = per2.power.V_flow, ySup = per2.power.P, ensureMonotonicity = false)Measured power
Modelica.Units.SI.Powerpow3Buildings.Utilities.Math.Functions.smoothInterpolation(x = m3_flow.y/rhoCon, xSup = per3.power.V_flow, ySup = per3.power.P, ensureMonotonicity = false)Measured power
Buildings.Fluid.Movers.BaseClasses.FlowMachineInterfaceeff1Flow machine interface using power characteristic
Buildings.Fluid.Movers.BaseClasses.FlowMachineInterfaceeff2Flow machine interface using power Euler correlation
Buildings.Fluid.Movers.BaseClasses.FlowMachineInterfaceeff3Flow machine interface using power Euler correlation
Modelica.Blocks.Sources.Constanty1Control signal
Modelica.Blocks.Sources.ConstantrhoDensity
Modelica.Blocks.Sources.Constanty2Reduced speed y = 3400/4100 = 0.829
Modelica.Blocks.Sources.Constanty3Reduced speed y = 2500/4100 = 0.610
Modelica.Blocks.Sources.Rampm1_flowMass flow rate
Modelica.Blocks.Sources.Rampm2_flowMass flow rate
Modelica.Blocks.Sources.Rampm3_flowMass flow rate

Revisions

  • March 18, 2022, by Hongxiang Fu:
    First implementation. This is for #2668.