<p class="MsoNormal">Fred,</p><p class="MsoNormal"><br></p><p class="MsoNormal">I think you will have to modify Type668 to do that. I suggest you take a look at Type666 water-cooled chiller which works at part load by defining a setpoint on outlet load temperature. Instead of calculating part load ratio as a result of desired outlet water temperature, you can directly specify 10%, 50% and so on. You will also need some data on fraction of full load power at given part load ratio, to properly model heat pump performance at part load.</p>
<p class="MsoNormal"><br></p><p class="MsoNormal">Hope this helps.</p><p class="MsoNormal"><br></p><p class="MsoNormal">Best regards,</p><p class="MsoNormal">Knut Erik Enerstvedt</p><p class="MsoNormal"><br></p><p class="MsoNormal">
<br></p><p class="MsoNormal">>Does anyone know of a way to make part load operation work
in Type668?</p>
<p class="MsoNormal"> </p>
<p class="MsoNormal">>The performance maps are based on entering conditions on the
evaporator and condenser side. However, there is no direct way to >make type668
run at 10%, 50%, etc.</p>
<p class="MsoNormal"> </p>
<p class="MsoNormal">>The work around I have used in the past is dividing the
performance map by 50% to reflect two stages of operation and so on. Then
>setting up valves and controls to route the flow correctly. </p>
<p class="MsoNormal"> </p>
<p class="MsoNormal">>The HP I am modeling has a 10:1 turn down ratio and I don’t
want to make 10 heat pumps each with 10% of the total capacity of a >single
unit. </p>
<p class="MsoNormal"> </p>
<p class="MsoNormal">>Please advise,</p>
<p class="MsoNormal"> </p>
<p class="MsoNormal">>Fred</p>