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Update documentation for new approach
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FWuellhorst committed Apr 3, 2024
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Original file line number Diff line number Diff line change
Expand Up @@ -102,6 +102,37 @@ initial algorithm
Also, icing is disabled as the performance degradation
is already contained in the data.
</p>
<h4>Sizing</h4>
<p>
At the nominal conditions, the refrigerant cycle model will
calculate the unscaled nominal heat flow rate, which is
named <code>QHeaNoSca_flow_nominal</code> for heat pumps and
<code>QCooNoSca_flow_nominal</code> for chillers.
This value is probably
different from <code>QUse_flow_nominal</code> which is for sizing.
For example, suppose you need a 7.6 kW heat pump,
but the datasheets only provides 5 kW and 10 kW options.
In such cases, the performance data and relevant parameters
are scaled using a scaling factor <code>scaFac</code>.
Resulting, the refrigerant machine can supply more or less heat with
the COP staying constant. However, one has to make sure
that the movers in use also scale with this factor.
Note that most parameters are scaled linearly. Only the
pressure differences are scaled quadratically due to
the linear scaling of the mass flow rates and the
basic assumption:
<p align=\"center\" style=\"font-style:italic;\">
k = m&#775; &frasl; &radic;<span style=\"text-decoration:overline;\">&nbsp;&Delta;p &nbsp;</span>
</p>
<p>
Both <code>QHeaNoSca_flow_nominal</code> or <code>QCooNoSca_flow_nominal</code>
and <code>scaFac</code>
are calculated in the refrigerant cycle models.
</p>
<p>
Please read the documentation of the model for heating at
<a href=\"modelica://IBPSA.Fluid.HeatPumps.ModularReversible.RefrigerantCycle.TableData2D\">
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42 changes: 2 additions & 40 deletions IBPSA/Fluid/HeatPumps/ModularReversible/UsersGuide.mo
Original file line number Diff line number Diff line change
@@ -1,4 +1,4 @@
within IBPSA.Fluid.HeatPumps.ModularReversible;
within IBPSA.Fluid.HeatPumps.ModularReversible;
package UsersGuide
"User's Guide for modular reversible heat pump and chiller models"
extends Modelica.Icons.Information;
Expand Down Expand Up @@ -379,9 +379,6 @@ The following tables summarizes the possible options.
<li>
evaporator temperature <code>TEva_nominal</code>,
</li>
<li>
compressor speed <code>y_nominal</code>.
</li>
</ul>
<p>
Depending on the model in use, this may be in- out outlet.
Expand All @@ -401,42 +398,7 @@ The following tables summarizes the possible options.
As reversible devices have typically a four-way-valve and a single
compressor, you have to make sure that the values for <code>PEle_nominal</code>
are similar between heating and cooling. The pre-configured models
already contain assumptions in this regard.
</p>
<h4>Sizing</h4>
<p>
At the nominal conditions, the refrigerant cycle model will
calculate the unscaled nominal heat flow rate, which is
named <code>QHeaNoSca_flow_nominal</code> for heat pumps and
<code>QCooNoSca_flow_nominal</code> for chillers.
This value is probably
different from <code>QUse_flow_nominal</code> which is for sizing.
For example, suppose you need a 7.6 kW heat pump,
but the datasheets only provides 5 kW and 10 kW options.
In such cases, the performance data and relevant parameters
are scaled using a scaling factor <code>scaFac</code>.
Resulting, the refrigerant machine can supply more or less heat with
the COP staying constant. However, one has to make sure
that the movers in use also scale with this factor.
Note that most parameters are scaled linearly. Only the
pressure differences are scaled quadratically due to
the linear scaling of the mass flow rates and the
basic assumption:
<p align=\"center\" style=\"font-style:italic;\">
k = m&#775; &frasl; &radic;<span style=\"text-decoration:overline;\">&nbsp;&Delta;p &nbsp;</span>
</p>
<p>
Both <code>QHeaNoSca_flow_nominal</code> or <code>QCooNoSca_flow_nominal</code>
and <code>scaFac</code>
are calculated in the refrigerant cycle models.
The <code>scaFac</code> is propagated to the
uppermost layer of the <code>ModularReversible</code> models.
If both heating and cooling operation is enabled
using <code>use_rev</code>, the scaling of the secondary
operation is overwritten by the one in the primary operation.
warn about deviations if they are too large.
</p>
<h4>Safety controls</h4>
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