Skip to content
New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Add coil model, plus validation and example #1549

Merged
merged 14 commits into from
Nov 29, 2021
Merged

Add coil model, plus validation and example #1549

Show file tree
Hide file tree
Changes from 4 commits
Commits
Show all changes
14 commits
Select commit Hold shift + click to select a range
c4e40a0
Add coil model, plus validation and example
AntoineGautier Nov 10, 2021
d228651
Add results
AntoineGautier Nov 10, 2021
6f694c6
Merge branch 'master' into issue1109_wetCoilEpsNTU
mwetter Nov 11, 2021
b340081
Merge branch 'master' into issue1109_wetCoilEpsNTU
Mathadon Nov 15, 2021
5910ba7
Update IBPSA/Fluid/HeatExchangers/BaseClasses/WetCoilDryRegime.mo
AntoineGautier Nov 22, 2021
ab0291b
Format documentation
AntoineGautier Nov 22, 2021
9c5283f
Merge branch 'issue1109_wetCoilEpsNTU' of github.com:ibpsa/modelica-i…
AntoineGautier Nov 22, 2021
11879cd
Explicit equation for output variables, corrections in documentation
AntoineGautier Nov 22, 2021
38f7a34
Guard against dT1=dT2 when computing LMTD
AntoineGautier Nov 22, 2021
921749c
Merge branch 'master' into issue1109_wetCoilEpsNTU
mwetter Nov 22, 2021
81658b1
Merge branch 'master' into issue1109_wetCoilEpsNTU
mwetter Nov 23, 2021
c832c4f
Reintroduce changes from MBL#2711, fix description strings
AntoineGautier Nov 24, 2021
1164d64
Reintroduce issue number in LMTD
AntoineGautier Nov 25, 2021
24b1313
Merge branch 'master' into issue1109_wetCoilEpsNTU
mwetter Nov 29, 2021
File filter

Filter by extension

Filter by extension
Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
103 changes: 103 additions & 0 deletions IBPSA/Fluid/HeatExchangers/BaseClasses/WetCoilDryRegime.mo
View file
Open in desktop
Original file line number Diff line number Diff line change
@@ -0,0 +1,103 @@
within IBPSA.Fluid.HeatExchangers.BaseClasses;
model WetCoilDryRegime
"Fully dry coil model"

// - water
input Modelica.SIunits.ThermalConductance UAWat
"UA for water side";
input Modelica.SIunits.MassFlowRate mWat_flow
"Mass flow rate for water";
input Modelica.SIunits.MassFlowRate mWatNonZer_flow(min=Modelica.Constants.eps)
"Mass flow rate for water, bounded away from zero";

input Modelica.SIunits.SpecificHeatCapacity cpWat
"Specific heat capacity of water";
input Modelica.SIunits.Temperature TWatIn
"Water temperature at inlet";
// -- air
input Modelica.SIunits.ThermalConductance UAAir
"UA for air side";
input Modelica.SIunits.MassFlowRate mAir_flow(min=Modelica.Constants.eps)
"Mass flow rate of air";
input Modelica.SIunits.MassFlowRate mAirNonZer_flow(min=Modelica.Constants.eps)
"Mass flow rate for air, bounded away from zero";
input Modelica.SIunits.SpecificHeatCapacity cpAir
"Specific heat capacity of moist air at constant pressure";
input Modelica.SIunits.Temperature TAirIn
"Temperature of air at inlet";
// -- misc.
input IBPSA.Fluid.Types.HeatExchangerFlowRegime cfg
"The flow regime of the heat exchanger";
input Modelica.SIunits.MassFlowRate mAir_flow_nominal
"Nominal mass flow rate for air";
input Modelica.SIunits.MassFlowRate mWat_flow_nominal
"Nominal mass flow rate for water";

parameter Real delta = 1E-3 "Small value used for smoothing";

output Modelica.SIunits.HeatFlowRate QTot_flow
"Heat transferred from water to air";
output Modelica.SIunits.Temperature TWatOut
"Temperature of water at outlet";
output Modelica.SIunits.Temperature TAirOut
"Temperature of air at the outlet";
output Real eps(min=0, max=1, unit="1")
"Effectiveness for heat exchanger";
Modelica.SIunits.ThermalConductance CWat_flow=mWat_flow*cpWat
"Capacitance rate of water";
Modelica.SIunits.ThermalConductance CAir_flow=mAir_flow*cpAir
"Capacitance rate of air";
Modelica.SIunits.ThermalConductance CMin_flow_nominal=
min(mAir_flow_nominal*cpAir,mWat_flow_nominal*cpWat)
"Minimum capacity rate";
Modelica.SIunits.ThermalConductance CMax_flow_nominal=
max(mAir_flow_nominal*cpAir,mWat_flow_nominal*cpWat)
"Maximum capacity rate";
Modelica.SIunits.ThermalConductance CMin_flow=
IBPSA.Utilities.Math.Functions.smoothMin(
x1=CAir_flow,x2=CWat_flow,deltaX=1E-3*(CMax_flow_nominal-CMin_flow_nominal))
"Minimum capacity rate";
Modelica.SIunits.ThermalConductance UA
"Overall heat transfer coefficient";
output Modelica.SIunits.Temperature TSurAirOut
"Surface Temperature at air outlet";
equation
UA = 1/ (1 / UAAir + 1 / UAWat);

eps=epsilon_C(
UA=UA,
C1_flow=CWat_flow,
C2_flow=CAir_flow,
flowRegime=Integer(cfg),
CMin_flow_nominal= CMin_flow_nominal,
CMax_flow_nominal=CMax_flow_nominal,
delta= delta);

QTot_flow = eps*CMin_flow*(TAirIn-TWatIn);
TAirOut=TAirIn-QTot_flow/(mAirNonZer_flow*cpAir);
Mathadon marked this conversation as resolved.
Show resolved Hide resolved
TWatOut=TWatIn+QTot_flow/(mWatNonZer_flow*cpWat);

(TAirOut-TSurAirOut)*UAAir=(TSurAirOut-TWatIn)*UAWat;
Mathadon marked this conversation as resolved.
Show resolved Hide resolved

annotation (Icon(coordinateSystem(preserveAspectRatio=false), graphics={
Rectangle(
extent={{-100,100},{100,-100}},
lineColor={28,108,200},
fillColor={255,213,170},
fillPattern=FillPattern.Solid)}), Diagram(
coordinateSystem(preserveAspectRatio=false)),
Documentation(revisions="<html>
<ul>
<li>Jan 21, 2021, by Donghun Kim:<br/>First implementation.
AntoineGautier marked this conversation as resolved.
Show resolved Hide resolved
</li>
</ul>
</html>", info="<html>
<p>This model implements the calculation for a 100% dry coil.</p>
<p>
See
<a href=\"modelica://IBPSA.Fluid.HeatExchangers.DryCoilEffectivenessNTU\">
IBPSA.Fluid.HeatExchangers.DryCoilEffectivenessNTU</a>
for documentation.
</p>
</html>"));
end WetCoilDryRegime;
Loading