Buildings.Fluid.Chillers.ModularReversible.Validation

Package for model validation

Information

This package contains models that validate the modular reversible chiller models using comparative validation against the Carnot model: Buildings.Fluid.Chillers.Examples.Carnot_y

Extends from Modelica.Icons.ExamplesPackage (Icon for packages containing runnable examples).

Package Content

Name	Description
Carnot_y	Example using the Carnot model approach
ConstantCarnotEffectiveness	Validation case for modular Carnot approach
TableData2D	Validation case for table data approach
TableData2DLoadDep	Test model for chiller electric reformulated EIR
TableData2DLoadDep_AirCooled	Test model for chiller electric reformulated EIR
TableData2DLoadDep_HeatRecovery	Test model for chiller electric reformulated EIR
BaseClasses	Package with partial validation models

Buildings.Fluid.Chillers.ModularReversible.Validation.Carnot_y

Example using the Carnot model approach

Information

Validation case for Buildings.Fluid.Chillers.Carnot_y, duplicate of the example Buildings.Fluid.Chillers.Examples.Carnot_y.

Extends from Buildings.Fluid.HeatPumps.ModularReversible.Validation.Comparative.BaseClasses.PartialComparison (Partial model to allow heat pump and chiller model comparison), Modelica.Icons.Example (Icon for runnable examples).

Parameters

Modelica definition

Buildings.Fluid.Chillers.ModularReversible.Validation.ConstantCarnotEffectiveness

Validation case for modular Carnot approach

Information

Validation case for Buildings.Fluid.Chillers.ModularReversible.RefrigerantCycle.ConstantCarnotEffectiveness.

Extends from BaseClasses.PartialModularComparison (Partial model for comparison to the Carnot model), Modelica.Icons.Example (Icon for runnable examples).

Parameters

Modelica definition

Buildings.Fluid.Chillers.ModularReversible.Validation.TableData2D

Validation case for table data approach

Information

Validation case for Buildings.Fluid.Chillers.ModularReversible.RefrigerantCycle.TableData2D.

Extends from BaseClasses.PartialModularComparison (Partial model for comparison to the Carnot model), Modelica.Icons.Example (Icon for runnable examples).

Parameters

Modelica definition

Buildings.Fluid.Chillers.ModularReversible.Validation.TableData2DLoadDep

Test model for chiller electric reformulated EIR

Information

This model validates Buildings.Fluid.Chillers.ModularReversible.TableData2DLoadDep against the polynomial chiller model Buildings.Fluid.Chillers.ElectricReformulatedEIR for water-cooled chiller applications.

• The validation setup is duplicated from Buildings.Fluid.Chillers.Examples.ElectricReformulatedEIR and the component ref reads the reference results obtained from that model.
• The chiller model is configured to interpolate capacity and power along the evaporator leaving temperature and the condenser leaving temperature.
• The performance data are generated with the same polynomial equations as Buildings.Fluid.Chillers.ElectricReformulatedEIR, using polynomial coefficients from the same data record as the one used in the reference example model, that is Buildings.Fluid.Chillers.Data.ElectricReformulatedEIR.ReformEIRChiller_McQuay_WSC_471kW_5_89COP_Vanes.

Results analysis

There is good agreement with the reference results, except during the model time interval [7200, 7900] s, where the polynomial model computes zero capacity and power. This discrepancy stems from the existence of multiple solutions in the polynomial model. The reference results show one solution with TEvaLvg = TEvaEnt = 20 °C. This temperature exceeds the upper limit per.TEvaLvgMax of the polynomial model's validity range, resulting in a negative capacity that is bounded to 0 in the polynomial model. The data table model reveals that an alternative solution exists where the CHW setpoint is met with a PLR value of about 74 %.

Extends from Modelica.Icons.Example (Icon for runnable examples), Buildings.Fluid.Chillers.Examples.BaseClasses.PartialElectric (Base class for test model of chiller electric EIR).

Parameters

Modelica definition

Buildings.Fluid.Chillers.ModularReversible.Validation.TableData2DLoadDep_AirCooled

Test model for chiller electric reformulated EIR

Information

This model validates Buildings.Fluid.Chillers.ModularReversible.TableData2DLoadDep against the polynomial chiller model Buildings.Fluid.Chillers.ElectricEIR for air-cooled chiller applications.

• The validation setup is duplicated from Buildings.Fluid.Chillers.Examples.ElectricEIR_AirCooled and the component ref reads the reference results obtained from that model.
• The chiller model is configured to interpolate capacity and power along the evaporator leaving temperature and the condenser entering temperature.
• The performance data are generated with the same polynomial equations as Buildings.Fluid.Chillers.ElectricEIR, using polynomial coefficients from the same data record as the one used in the reference example model, that is Buildings.Fluid.Chillers.Data.ElectricEIR.ElectricEIRChiller_York_YCAL0033EE_101kW_3_1COP_AirCooled.

Results analysis

There is good agreement with the reference results, except during the time interval where the PLR value exceeds 1. In this interval the polynomial model computes a significantly higher cooling heat flow rate (in negative value) and a slightly higher power. This discrepancy occurs because the polynomial model calculates the heat flow rate at PLR ≤ 1 while calculating power at PLR ≤ per.PLRMax. Consequently, when PLR increases between 1 and per.PLRMax, input power increases according to the polynomial EIRFunPLR, but the heat flow rate only varies due to the effect of the increasing leaving temperature as the setpoint is no longer met. This appears as a deficiency in the polynomial model that is resolved in the data table model.

Extends from Modelica.Icons.Example (Icon for runnable examples), Buildings.Fluid.Chillers.Examples.BaseClasses.PartialElectric_AirCooled (Base class for test model of chiller electric EIR with air-cooled condenser).

Parameters

Modelica definition

Buildings.Fluid.Chillers.ModularReversible.Validation.TableData2DLoadDep_HeatRecovery

Test model for chiller electric reformulated EIR

Information

This model validates Buildings.Fluid.Chillers.ModularReversible.TableData2DLoadDep against the polynomial chiller model Buildings.Fluid.Chillers.ElectricEIR for heat recovery chiller applications.

• The validation setup is duplicated from Buildings.Fluid.Chillers.Examples.ElectricEIR_AirCooled and the component ref reads the reference results obtained from that model.
• The chiller model is configured to interpolate capacity and power along the evaporator leaving temperature and the condenser entering temperature.
• The performance data are generated with the same polynomial equations as Buildings.Fluid.Chillers.ElectricEIR, using polynomial coefficients from the same data record as the one used in the reference example model, that is Buildings.Fluid.Chillers.Data.ElectricEIR.ElectricEIRChiller_York_YCAL0033EE_101kW_3_1COP_AirCooled.

Results analysis

There is good agreement with the reference results, except during the model time interval [7500, 8100] s, where the polynomial model computes lower power. During this period, the polynomial model calculates lower power due to the evaporator leaving temperature exceeding the maximum threshold upper limit per.TEvaLvgMax. While the data table model does not extrapolate beyond the temperature values provided in the performance data file, the reference model continues using polynomial evaluation of capacity and power outside of the validity range. Consequently, the polynomial model computes a higher capacity, resulting in a lower PLR and reduced power during this interval.

Extends from Modelica.Icons.Example (Icon for runnable examples), Buildings.Fluid.Chillers.Examples.BaseClasses.PartialElectric (Base class for test model of chiller electric EIR).

Parameters

Modelica definition