modelCooler

0D model of a dry-cooler

Extends from SolarTherm.Media.CO2.PropCO2.

Information

The overall conductance UA of the cooler is calculated with a logarithmic temperature difference. It is implemented in order to ensure convergence.

The Cp is varying from 4kJ/kg.K to 1.2 kJ/kg.K in this temperature/pressure range. It is therefore not very accurate but can be used for economical estimations.

The outlet temperature is fixed by the user. The electrical power necessary for the fans is estimated by P_elec/(Q_cooler*deltaT_average)=constante, for any sCO2/air HX. P_elec is the power to run the fans, Q_cooler is the energy exchanged with outside and deltaT_average is the average of T_CO2-T_amb, the average is taken between the outlet and the inlet.

Reference values (but not model) come from:

Sienicki, James J., Moisseytsev, Anton, and Lv, Qiuping. Dry Air Cooling and the sCO2 Brayton Cycle. Proceedings of the ASME Turbo Expo 2017: Turbomachinery Technical Conference and Exposition. Volume 9: Oil and Gas Applications; Supercritical CO2 Power Cycles; Wind Energy. Charlotte, North Carolina, USA. June 26–30, 2017. V009T38A015. ASME. https://doi.org/10.1115/GT2017-64042

Parameters

TypeNameDefaultDescription
Modelica.SIunits.ThermodynamicTemperatureT_amb313.15Outlet temperature in Kelvin
RealdeltaT_cooler15Approach difference of temperature at the outlet
Modelica.SIunits.PowerP_nom10^6
IntegerN_cool15Number of discretization of the cooler

Connectors

TypeNameDefaultDescription
Modelica.Fluid.Interfaces.FluidPort_aport_a
Modelica.Fluid.Interfaces.FluidPort_bport_b

Components

TypeNameDefaultDescription
Modelica.Blocks.Types.ExternalCombiTable2DtableIDh_p_s (from PropCO2)Modelica.Blocks.Types.ExternalCombiTable2D(tableName = "Enthalpy", fileName = Modelica.Utilities.Files.loadResource("modelica://SolarTherm/Data/CO2/Props_from_P_S.txt"), table = fill(0.0, 0, 2), smoothness = Modelica.Blocks.Types.Smoothness.LinearSegments)
Modelica.Blocks.Types.ExternalCombiTable2DtableIDd_p_h (from PropCO2)Modelica.Blocks.Types.ExternalCombiTable2D(tableName = "Density", fileName = Modelica.Utilities.Files.loadResource("modelica://SolarTherm/Data/CO2/Props_from_P_H.txt"), table = fill(0.0, 0, 2), smoothness = Modelica.Blocks.Types.Smoothness.LinearSegments)
Modelica.Blocks.Types.ExternalCombiTable2DtableIDT_p_h (from PropCO2)Modelica.Blocks.Types.ExternalCombiTable2D(tableName = "Temperature", fileName = Modelica.Utilities.Files.loadResource("modelica://SolarTherm/Data/CO2/Props_from_P_H.txt"), table = fill(0.0, 0, 2), smoothness = Modelica.Blocks.Types.Smoothness.LinearSegments)
Modelica.Blocks.Types.ExternalCombiTable2DtableIDh_p_T (from PropCO2)Modelica.Blocks.Types.ExternalCombiTable2D(tableName = "Enthalpy", fileName = Modelica.Utilities.Files.loadResource("modelica://SolarTherm/Data/CO2/Props_from_P_T.txt"), table = fill(0.0, 0, 2), smoothness = Modelica.Blocks.Types.Smoothness.LinearSegments)
Modelica.Fluid.Systemsystem
SolarTherm.Types.Conductance[N_cool - 1]UA_disConductance of the cooler per sub-HX
Modelica.SIunits.HeatFlowRateQ_disHeat flow rate dispatched per sub-HX in the cooler
Modelica.SIunits.ThermodynamicTemperatureT_CO2
Modelica.SIunits.HeatFlowRateQ_coolerHeat flow rate in the cooler
SolarTherm.Types.ConductanceUA_coolerOverall conductance of the cooler
SolarTherm.Types.SpecificExergyex_ddestroyed exergy
RealdeltaT_lmlogarithmic temperature difference
RealdeltaTdifference with the ambiant air at the inlet and outlet
Modelica.SIunits.PowerP_coolingPower used by the fans to cool the fluid
RealdeltaT_aveaverage difference of temperature with the ambiant

Contents

NameDescription
MedPB