<html><body><div style="color:#000; background-color:#fff; font-family:verdana, helvetica, sans-serif;font-size:10pt"><div id="yiv1525465243" class="" style=""><div class="" style=""><div style="color:#000;background-color:#fff;font-family:verdana, helvetica, sans-serif;font-size:10pt;" class=""><div id="yiv1525465243yui_3_16_0_6_1408475106782_4" class="" style=""><span id="yiv1525465243yui_3_16_0_6_1408475106782_31" class="" style="">Hi Jeff,</span></div><div id="yiv1525465243yui_3_16_0_6_1408475106782_4" style="color:rgb(0, 0, 0);font-size:13.600000381469727px;font-family:verdana, helvetica, sans-serif;font-style:normal;background-color:transparent;" class=""><span class="" style=""><br style=""></span></div><div id="yiv1525465243yui_3_16_0_6_1408475106782_4" style="color:rgb(0, 0, 0);font-size:13.600000381469727px;font-family:verdana, helvetica, sans-serif;font-style:normal;background-color:transparent;" class="">Even it is not realistic, but I
feel there is a lag in the mass flow rate at the outlet 1 of (type 11f) <span class="" style="font-size: 10pt;">by one</span><span class="" style="font-size: 10pt;"> </span><span class="" style="font-size: 10pt;"></span><span class="" style="font-size: 10pt;"><span id="e4fed84a-9295-417c-bac2-2c91932a6b7d" ginger_software_uiphraseguid="bcea80d1-941b-4c79-a33f-6753c578d9e5" class="GINGER_SOFTWARE_mark" style="">timestep</span>, </span><span class="" style="background-color: transparent;">and</span><span class="" style="background-color: transparent;"> I think that causes the outlet flow rate from the CT loop being greater than the rated flow of the pump.</span><br class="" style=""></div><div id="yiv1525465243yui_3_16_0_6_1408475106782_4" style="color:rgb(0, 0, 0);font-size:13.600000381469727px;font-family:verdana, helvetica, sans-serif;font-style:normal;background-color:transparent;" class=""><br></div><div
id="yiv1525465243yui_3_16_0_6_1408475106782_4" style="color:rgb(0, 0, 0);font-size:13.600000381469727px;font-family:verdana, helvetica, sans-serif;font-style:normal;background-color:transparent;" class=""><span style="background-color: transparent;">However, the problem was solved when I used TESS diverting valve (type 647) instead of (type 11f) and I am not facing any errors or warnings. </span><span class="" style="background-color: transparent;">I didn't change anything in my controlling equations that being used in the W-interpreter (I </span><span class="" style="font-size: 10pt; background-color: transparent;">just</span><span class="" style="font-size: 10pt; background-color: transparent;"> </span><span class="" style="background-color: transparent;">added another out </span><span class="" style="background-color: transparent;"><span id="7d93ef66-a88d-40eb-879c-4a2638faac20"
ginger_software_uiphraseguid="ebd9a32f-1a3e-45a1-a5d8-43f256f76c48" class="GINGER_SOFTWARE_mark">for</span></span><span class="" style="background-color: transparent;"> the CT mass fraction)</span></div><div id="yiv1525465243yui_3_16_0_6_1408475106782_4" style="color:rgb(0, 0, 0);font-size:13.600000381469727px;font-family:verdana, helvetica, sans-serif;font-style:normal;background-color:transparent;" class=""><br></div><div id="yiv1525465243yui_3_16_0_6_1408475106782_4" style="color:rgb(0, 0, 0);font-size:13.600000381469727px;font-family:verdana, helvetica, sans-serif;font-style:normal;background-color:transparent;" class=""><span class="" style="background-color: transparent;">Thank you so much to remind me to use TESS lib<br class="" style=""></span></div><div id="yiv1525465243yui_3_16_0_6_1408475106782_4" style="color:rgb(0, 0, 0);font-size:13.600000381469727px;font-family:verdana, helvetica,
sans-serif;font-style:normal;background-color:transparent;" class=""><span class="" style="background-color: transparent;"><br class="" style=""></span></div><div id="yiv1525465243yui_3_16_0_6_1408475106782_4" style="color:rgb(0, 0, 0);font-size:13.600000381469727px;font-family:verdana, helvetica, sans-serif;font-style:normal;background-color:transparent;" class=""><br class="" style=""></div><div id="yiv1525465243yui_3_16_0_6_1408475106782_4" style="color:rgb(0, 0, 0);font-size:13.600000381469727px;font-family:verdana, helvetica, sans-serif;font-style:normal;background-color:transparent;" class=""><span id="yiv1525465243yui_3_16_0_6_1408475106782_110" class="" style="">Kind regards,</span></div><div id="yiv1525465243yui_3_16_0_6_1408475106782_4" style="color:rgb(0, 0, 0);font-size:13.600000381469727px;font-family:verdana, helvetica, sans-serif;font-style:normal;background-color:transparent;" class=""><span
id="yiv1525465243yui_3_16_0_6_1408475106782_114" class="" style="">Shahen</span></div><div id="yiv1525465243yui_3_16_0_6_1408475106782_6" class="" style=""></div><div id="yiv1525465243yui_3_16_0_6_1408475106782_8" class="" style=""> </div><div id="yiv1525465243yui_3_16_0_6_1408475106782_10" class="" style=""><i id="yiv1525465243yui_3_16_0_1_1408475106782_4024" class="" style=""><font id="yiv1525465243yui_3_16_0_1_1408475106782_4023" size="3" class="" style=""></font></i><div id="yiv1525465243yui_3_16_0_1_1408475106782_4022" class="" style=""><i class="" style=""><br clear="none" class="" style=""></i></div><i class="" style=""></i><font size="3" class="" style=""></font></div> <div class="" id="yiv1525465243yui_3_16_0_1_1408475106782_4479" style=""><div style="font-family: 'Helvetica Neue', 'Segoe UI', Helvetica, Arial, 'Lucida Grande', sans-serif; font-size: 12.800000190734863px;" class="">Shahen,</div><div style="font-family: 'Helvetica Neue',
'Segoe UI', Helvetica, Arial, 'Lucida Grande', sans-serif; font-size: 12.800000190734863px;" class="">I suggest you use the TRACE command and check to see what the controller is producing for a signal through all iterations of the <span id="3ace55a9-01ef-4130-b4dd-119c8999a221" ginger_software_uiphraseguid="6ba632ee-d014-4805-ad26-f53d92089f46" class="GINGER_SOFTWARE_mark" style="">timestep</span>. It's very possible that the simulation is not converging and you are seeing the result of that non-convergence. Make sure you are using a small <span id="1c699f50-11e6-4a2d-9346-10a3b8692c00" ginger_software_uiphraseguid="2b5b75c7-fcd2-4110-95da-7a2bb4533c33" class="GINGER_SOFTWARE_mark" style="">timestep</span>, <span id="706b5ae5-ba30-4f79-bc5e-82d3d4b7c091" ginger_software_uiphraseguid="2b5b75c7-fcd2-4110-95da-7a2bb4533c33" class="GINGER_SOFTWARE_mark" style="">have</span> pipes for capacitance, etc. We control towers all the <span
id="d74a6ea3-15e1-4ea6-92a7-8583729d9414" ginger_software_uiphraseguid="4b83929b-a99f-4803-b9e7-77b02e271ea9" class="GINGER_SOFTWARE_mark" style="">time but</span> use the tempering valve controller module in the TESS HVAC Library and not an external controller.</div><div style="font-family: 'Helvetica Neue', 'Segoe UI', Helvetica, Arial, 'Lucida Grande', sans-serif; font-size: 12.800000190734863px;" class=""> </div><div style="font-family: 'Helvetica Neue', 'Segoe UI', Helvetica, Arial, 'Lucida Grande', sans-serif; font-size: 12.800000190734863px;" class="">Jef</div><br clear="none" class="" style=""></div><div class="" id="yiv1525465243yqt16404" style=""><div class="" id="yiv1525465243yui_3_16_0_6_1408475106782_13" style="display: none;"> <div class="" id="yiv1525465243yui_3_16_0_1_1408475106782_4468" style="font-family:verdana, helvetica, sans-serif;font-size:10pt;"> <div class="" id="yiv1525465243yui_3_16_0_1_1408475106782_4467"
style="font-family:HelveticaNeue, Helvetica Neue, Helvetica, Arial, Lucida Grande, sans-serif;font-size:12pt;"> <div dir="ltr" class="" style=""> <font size="2" face="Arial" class="" style=""> On Tuesday, August 19, 2014 5:31 PM, Jeff Thornton <thornton@tess-inc.com> wrote:<br clear="none" class="" style=""> </font> </div> <br clear="none" class="" style=""><br clear="none" class="" style=""> <div class="" id="yiv1525465243yui_3_16_0_1_1408475106782_4466" style=""><div id="yiv1525465243" class="" style=""><div id="yiv1525465243yui_3_16_0_1_1408475106782_4465" class="" style="">
<div id="yiv1525465243yui_3_16_0_1_1408475106782_4478" class="" style="">Shahen,</div>
<div id="yiv1525465243yui_3_16_0_1_1408475106782_4868" class="" style="">I suggest you use the TRACE command and check to see what the controller is producing for a signal through all iterations of the <span class="" id="yiv15254652439935bb72-6e65-403a-b16d-5e9cd93f02c2" style=""><span id="9557af96-8478-4a06-a253-0b2f0729828f" ginger_software_uiphraseguid="08b8df78-8bbe-4b3a-8956-7617701b8f88" class="GINGER_SOFTWARE_mark" style="">timestep</span></span>. It's very possible that the simulation is not converging and you are seeing the result of that non-convergence. Make sure you are using a small <span class="" id="yiv1525465243b30bdc7e-93b2-4799-bca2-95aeefdbc94a" style=""><span id="f47cb21f-d304-44d1-b14d-b0b00e8d2498" ginger_software_uiphraseguid="41c25dca-55bc-4b8a-90aa-a75be6f97b62" class="GINGER_SOFTWARE_mark" style="">timestep</span></span>, <span class="" id="yiv15254652434b939102-a5f3-45e6-84c3-9d51cd28461b" style=""><span
id="34baa1ab-b09c-42fa-8070-f229f34b19b3" ginger_software_uiphraseguid="41c25dca-55bc-4b8a-90aa-a75be6f97b62" class="GINGER_SOFTWARE_mark" style="">have</span></span> pipes for capacitance, etc. We control towers all the <span class="" id="yiv152546524389c19e71-5814-4187-82bb-b94be7901397" style=""><span id="a04d7e28-d392-4db5-a55e-d4aec9e87afc" ginger_software_uiphraseguid="966f6f9c-e2e7-43b5-be6f-35ad6abac94a" class="GINGER_SOFTWARE_mark" style="">time but</span></span> use the tempering valve controller module in the TESS HVAC Library and not an external controller.</div>
<div id="yiv1525465243yui_3_16_0_1_1408475106782_4869" class="" style=""> </div>
<div id="yiv1525465243yui_3_16_0_1_1408475106782_4470" class="" style="">Jeff</div>
<div id="yiv1525465243yui_3_16_0_1_1408475106782_4464" class="" style=""> </div>
<div class="" id="yiv1525465243yqt90025" style=""><div id="yiv1525465243yui_3_16_0_1_1408475106782_4472" class="" style="">
<pre id="yiv1525465243yui_3_16_0_1_1408475106782_4471" class="" style="">---<br clear="none" class="" style="">Jeff <span class="" id="yiv1525465243015a6090-184a-4c87-b4bf-0bd8f8e133e1" style=""><span id="3d77030d-b070-4f73-ae48-6e6ec80bc466" ginger_software_uiphraseguid="31d7080a-bd06-4556-af35-050abfb93310" class="GINGER_SOFTWARE_mark" style="">Thornton
President</span></span> - TESS LLC
22 N. Carroll Street, <span class="" id="yiv1525465243d01e39e0-ee95-4f2e-b07c-c59fe5c31433" style=""><span id="f041a90e-0916-4ccb-aa26-8a2d6282e7a5" ginger_software_uiphraseguid="d8a9ff62-09f2-41cf-8a68-687400f60370" class="GINGER_SOFTWARE_mark" style="">Madison WI</span></span> USA 53703
Office: (608) 274-2577 Fax: (608) 278-1475
www.tess-inc.com
E-Mail: thornton@tess-inc.com
</pre>
</div>
<div class="" style="">On 08/19/2014 8:43 am, Shahen Fakhraldin wrote:</div>
<blockquote id="yiv1525465243yui_3_16_0_1_1408475106782_4476" type="cite" style="padding-left:5px;border-left:#1010ff 2px solid;margin-left:5px;" class="">
<div class="" id="yiv1525465243yui_3_16_0_1_1408475106782_4475" style="color:#000;background-color:#fff;font-family:verdana, helvetica, sans-serif;font-size:10pt;">
<div id="yiv1525465243" class="" style="">
<div id="yiv1525465243yui_3_16_0_1_1408475106782_4474" class="" style="">
<div class="" id="yiv1525465243yui_3_16_0_1_1408475106782_4473" style="color:#000;background-color:#fff;font-family:verdana, helvetica, sans-serif;font-size:10pt;">
<div id="yiv1525465243" class="" style="">
<div id="yiv1525465243yui_3_16_0_1_1408093370808_11245" class="" style="">
<div id="yiv1525465243yui_3_16_0_1_1408093370808_11244" style="background-color:#ffffff;" class="">
<div class="" id="yiv1525465243yui_3_16_0_6_1408026953904_4" style="color:#000000;font-family:verdana, helvetica, sans-serif;font-size:10pt;"><span id="yiv1525465243yui_3_16_0_6_1408026953904_15" class="" style="">Dear TRNSYS users,</span></div>
<div id="yiv1525465243yui_3_16_0_6_1408026953904_4" style="color:#000000;font-size:13.600000381469727px;font-style:normal;background-color:transparent;" class=""><span id="yiv1525465243yui_3_16_0_6_1408026953904_21" class="" style=""> </span></div>
<div class="" id="yiv1525465243yui_3_16_0_6_1408026953904_4" style="font-family:verdana, helvetica, sans-serif;font-size:10pt;background-color:transparent;"><span class="" id="yiv1525465243yui_3_16_0_6_1408026953904_26" style="color:#000000;font-family:verdana, helvetica, sans-serif;font-size:13.600000381469727px;font-style:normal;">I am trying to control a cooling tower of absorption chiller by </span><span id="yiv1525465243yui_3_16_0_1_1408026953904_2997" style="background-color:transparent;" class="">using a three-way valve (type 11f) to mix between the returned water from the chiller and the water coming from the cooling tower (type 51b). </span></div>
<div class="" id="yiv1525465243yui_3_16_0_6_1408026953904_4" style="color:#000000;font-family:verdana, helvetica, sans-serif;font-size:13.600000381469727px;font-style:normal;background-color:transparent;"><span style="background-color:transparent;" class=""> </span></div>
<div class="" id="yiv1525465243yui_3_16_0_6_1408026953904_4" style="color:#000000;font-family:verdana, helvetica, sans-serif;font-size:13.600000381469727px;font-style:normal;background-color:transparent;"><span id="yiv1525465243yui_3_16_0_6_1408026953904_43" style="background-color:transparent;" class="">I assumed the range of temperature of mixing 28 - 33 C</span><span id="yiv1525465243yui_3_16_0_1_1408026953904_3211" style="font-size:10pt;background-color:transparent;" class=""> (over 33 C the flow completely will be through the cooling tower), and </span><span id="yiv1525465243yui_3_16_0_1_1408093370808_12173" style="font-size:10pt;background-color:transparent;" class="">I am using (W-</span><span style="font-size:10pt;background-color:transparent;" class=""><span id="yiv1525465243e2fc-7847-4602-a716-5a20b00a7808" class="" style="">interpreter</span></span><span id="yiv1525465243yui_3_16_0_1_1408093370808_12174"
style="font-size:10pt;background-color:transparent;" class="">) to produce the mixer (diverter) signal.</span></div>
<div class="" id="yiv1525465243yui_3_16_0_6_1408026953904_4" style="color:#000000;font-family:verdana, helvetica, sans-serif;font-size:10pt;font-style:normal;background-color:transparent;"> </div>
<div class="" id="yiv1525465243yui_3_16_0_6_1408026953904_4" style="color:#000000;font-family:verdana, helvetica, sans-serif;font-size:10pt;font-style:normal;background-color:transparent;">I am getting strange results where <span style="font-size:10pt;" class="">the inlet mass to the chiller (that comes from the cooling tower subsystem) </span><span style="font-size:10pt;background-color:transparent;" class="">is not equal to </span><span style="font-size:10pt;" class="">the inlet mass of the cooling tower subsystem (that comes from the chiller), even these mass rates exceeded the rated flow rate of the pump of cooling tower subsystem (type 114). </span><span style="font-size:10pt;background-color:transparent;" class="">Whereas </span><span style="font-size:10pt;background-color:transparent;" class="">if the diverter signal is fixed (from 0 to 1.0) I do not face this error</span></div>
<div class="" id="yiv1525465243yui_3_16_0_6_1408026953904_4" style="color:#000000;font-family:verdana, helvetica, sans-serif;font-size:10pt;font-style:normal;background-color:transparent;"> </div>
<div class="" id="yiv1525465243yui_3_16_0_6_1408026953904_4" style="color:#000000;font-family:verdana, helvetica, sans-serif;font-size:10pt;font-style:normal;background-color:transparent;">Did anyone try controlling a cooling tower in TRNSYS?</div>
<div id="yiv1525465243yui_3_16_0_6_1408026953904_4" style="background-color:transparent;" class=""> </div>
<div id="yiv1525465243yui_3_16_0_6_1408026953904_4" style="background-color:transparent;" class="">All kinds of help are very much appreciated.</div>
<div class="" id="yiv1525465243yui_3_16_0_6_1408026953904_4" style="color:#000000;font-family:verdana, helvetica, sans-serif;font-size:10pt;font-style:normal;background-color:transparent;"> </div>
<div class="" id="yiv1525465243yui_3_16_0_6_1408026953904_4" style="color:#000000;font-family:verdana, helvetica, sans-serif;font-size:13.600000381469727px;font-style:normal;background-color:transparent;"><span id="yiv1525465243yui_3_16_0_6_1408026953904_36" class="" style="">Kind regards,</span></div>
<div id="yiv1525465243yui_3_16_0_6_1408026953904_4" style="color:#000000;font-size:13.600000381469727px;font-style:normal;background-color:transparent;" class=""><span id="yiv1525465243yui_3_16_0_6_1408093370808_64" class="" style="">Shahen</span></div>
<div class="" id="yiv1525465243yui_3_16_0_6_1408026953904_6" style="color:#000000;font-family:verdana, helvetica, sans-serif;font-size:10pt;"> </div>
<div class="" id="yiv1525465243yui_3_16_0_6_1408026953904_8" style="color:#000000;font-family:verdana, helvetica, sans-serif;font-size:10pt;"> </div>
<div class="" id="yiv1525465243yui_3_16_0_6_1408026953904_10" style="color:#000000;font-family:verdana, helvetica, sans-serif;font-size:10pt;">
<div id="yiv1525465243yui_3_16_0_1_1408026953904_2883" class="" style=""> </div>
<span style="font-size:medium;" class=""></span></div>
</div>
</div>
</div>
</div>
</div>
</div>
</div>
<br clear="none" class="" style="">
<pre id="yiv1525465243yui_3_16_0_1_1408475106782_4477" class="" style="">_______________________________________________
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</pre>
</blockquote></div>
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