<div dir="ltr"><div>Thanks Jon for your explanation and advice. <br><br>I need to configure and simulate examples with supply, exhaust and combined supply and exhaust systems for teaching purposes only. The examples will be explored by mechanical engineering students. The focus is on sizing and evaluating the performance of the ventilation system and its components, and the idea is to configure the flow network in enet and simulate it in mfs without including the building and plant, at least at the beginning. Initially, the idea is to understand how enet and mfs work together.<br><br>The flow network configured in enet is:<br><br></div><img src="cid:ii_lnaft2ha0" alt="image.png" width="472" height="370"><br><div><div dir="ltr" class="gmail_signature" data-smartmail="gmail_signature"><div dir="ltr"><div><div dir="ltr"><div><div><div><div><div><br></div><div>The configuration file sup_vent is attached to this mail.<br></div><div><br></div><div>I will look at the material you suggested.<br><br>Best regards,<br><br>Clodoaldo.<br></div><div><br></div><div><b>Prof. Clodoaldo de O. Carvalho Filho, Dr.</b><br></div><span>Universidade Federal do Ceará</span><br>Depto. de Engenharia Mecânica<br></div></div>Lab. de Eficiência Energética no Conforto Ambiental - Coordenador<br></div>ASHRAE Fortaleza Student Branch - Advisor<br></div><br><div><div><br></div></div></div></div></div></div></div><br></div><br><div class="gmail_quote"><div dir="ltr" class="gmail_attr">Em seg., 2 de out. de 2023 às 05:14, Jon Hand <<a href="mailto:jon@esru.strath.ac.uk">jon@esru.strath.ac.uk</a>> escreveu:<br></div><blockquote class="gmail_quote" style="margin:0px 0px 0px 0.8ex;border-left:1px solid rgb(204,204,204);padding-left:1ex"><div class="msg-592585348297005737"> <div dir="ltr"> <div style="font-family:Aptos,Aptos_EmbeddedFont,Aptos_MSFontService,Calibri,Helvetica,sans-serif;font-size:12pt;color:rgb(0,0,0)"> Hello Clodoaldo,</div> <div style="font-family:Aptos,Aptos_EmbeddedFont,Aptos_MSFontService,Calibri,Helvetica,sans-serif;font-size:12pt;color:rgb(0,0,0)"> <br> </div> <div style="font-family:Aptos,Aptos_EmbeddedFont,Aptos_MSFontService,Calibri,Helvetica,sans-serif;font-size:12pt;color:rgb(0,0,0)"> The error is what we call a string buffer overflow - more characters are being written to</div> <div style="font-family:Aptos,Aptos_EmbeddedFont,Aptos_MSFontService,Calibri,Helvetica,sans-serif;font-size:12pt;color:rgb(0,0,0)"> a string variable than it can hold. The error is happening when it is trying to compose</div> <div style="font-family:Aptos,Aptos_EmbeddedFont,Aptos_MSFontService,Calibri,Helvetica,sans-serif;font-size:12pt;color:rgb(0,0,0)"> a menu. We would need to do some debugging while attempting to create the same</div> <div style="font-family:Aptos,Aptos_EmbeddedFont,Aptos_MSFontService,Calibri,Helvetica,sans-serif;font-size:12pt;color:rgb(0,0,0)"> network to get past this. To help us with this can you send a sketch of the network</div> <div style="font-family:Aptos,Aptos_EmbeddedFont,Aptos_MSFontService,Calibri,Helvetica,sans-serif;font-size:12pt;color:rgb(0,0,0)"> you wanted to create along with the names of the entities that you tried to use so</div> <div style="font-family:Aptos,Aptos_EmbeddedFont,Aptos_MSFontService,Calibri,Helvetica,sans-serif;font-size:12pt;color:rgb(0,0,0)"> the fault can be duplicated?</div> <div style="font-family:Aptos,Aptos_EmbeddedFont,Aptos_MSFontService,Calibri,Helvetica,sans-serif;font-size:12pt;color:rgb(0,0,0)"> <br> </div> <div style="font-family:Aptos,Aptos_EmbeddedFont,Aptos_MSFontService,Calibri,Helvetica,sans-serif;font-size:12pt;color:rgb(0,0,0)"> Until this can be done why not try an alternative approach?</div> <div style="font-family:Aptos,Aptos_EmbeddedFont,Aptos_MSFontService,Calibri,Helvetica,sans-serif;font-size:12pt;color:rgb(0,0,0)"> <br> </div> <div style="font-family:Aptos,Aptos_EmbeddedFont,Aptos_MSFontService,Calibri,Helvetica,sans-serif;font-size:12pt;color:rgb(0,0,0)"> It seems like a simple network. Is there a reason you do not use a simple box model</div> <div style="font-family:Aptos,Aptos_EmbeddedFont,Aptos_MSFontService,Calibri,Helvetica,sans-serif;font-size:12pt;color:rgb(0,0,0)"> of a thermal zone with it? This will us the much more common bps simulator to</div> <div style="font-family:Aptos,Aptos_EmbeddedFont,Aptos_MSFontService,Calibri,Helvetica,sans-serif;font-size:12pt;color:rgb(0,0,0)"> solve both the zone and the flow network - so you get the dynamics.</div> <div style="font-family:Aptos,Aptos_EmbeddedFont,Aptos_MSFontService,Calibri,Helvetica,sans-serif;font-size:12pt;color:rgb(0,0,0)"> <br> </div> <div style="font-family:Aptos,Aptos_EmbeddedFont,Aptos_MSFontService,Calibri,Helvetica,sans-serif;font-size:12pt;color:rgb(0,0,0)"> There are a number of YouTube videos which show aspects of setting up flow</div> <div style="font-family:Aptos,Aptos_EmbeddedFont,Aptos_MSFontService,Calibri,Helvetica,sans-serif;font-size:12pt;color:rgb(0,0,0)"> networks. Look in the ESP-r tutorials and ESP-r demonstrations videos here:</div> <div style="font-family:Aptos,Aptos_EmbeddedFont,Aptos_MSFontService,Calibri,Helvetica,sans-serif;font-size:12pt;color:rgb(0,0,0)"> <br> </div> <div style="font-family:Aptos,Aptos_EmbeddedFont,Aptos_MSFontService,Calibri,Helvetica,sans-serif;font-size:12pt;color:rgb(0,0,0)"> <a href="https://www.youtube.com/@jon.in.glasgow1989/playlists" id="m_4699208878548327058LPlnkOWALinkPreview" target="_blank">https://www.youtube.com/@jon.in.glasgow1989/playlists</a></div> <div style="font-family:Aptos,Aptos_EmbeddedFont,Aptos_MSFontService,Calibri,Helvetica,sans-serif;font-size:12pt;color:rgb(0,0,0)"> <br> </div> <div> <div id="m_4699208878548327058LPBorder_GTaHR0cHM6Ly93d3cueW91dHViZS5jb20vQGpvbi5pbi5nbGFzZ293MTk4OS9wbGF5bGlzdHM." style="width:100%;margin-top:16px;margin-bottom:16px;max-width:800px;min-width:424px"> <table id="m_4699208878548327058LPContainer298588" role="presentation" style="padding:12px 36px 12px 12px;width:100%;border:1px solid rgb(200,200,200);border-radius:2px"> <tbody> <tr valign="top" style="border-spacing:0px"> <td> <div id="m_4699208878548327058LPImageContainer298588" style="margin-right:12px;height:160px;overflow:hidden"> <a id="m_4699208878548327058LPImageAnchor298588" href="https://www.youtube.com/@jon.in.glasgow1989/playlists" target="_blank"><img id="m_4699208878548327058LPThumbnailImageId298588" alt="" height="160" style="display: block;" width="160" src="https://yt3.googleusercontent.com/ytc/APkrFKaDWu9hOdnj4SOFPxN5bZCKLfnEzXE0K2mldgSt=s900-c-k-c0x00ffffff-no-rj"></a></div> </td> <td style="width:100%"> <div id="m_4699208878548327058LPTitle298588" style="font-size:21px;font-weight:300;margin-right:8px;font-family:wf_segoe-ui_light,"Segoe UI Light","Segoe WP Light","Segoe UI","Segoe WP",Tahoma,Arial,sans-serif;margin-bottom:12px"> <a id="m_4699208878548327058LPUrlAnchor298588" href="https://www.youtube.com/@jon.in.glasgow1989/playlists" style="text-decoration:none" target="_blank">jon.in.glasgow</a></div> <div id="m_4699208878548327058LPMetadata298588" style="font-size:14px;font-weight:400;font-family:wf_segoe-ui_normal,"Segoe UI","Segoe WP",Tahoma,Arial,sans-serif;color:rgb(166,166,166)"> <a href="http://www.youtube.com" target="_blank">www.youtube.com</a></div> </td> </tr> </tbody> </table> </div> </div> <div style="font-family:Aptos,Aptos_EmbeddedFont,Aptos_MSFontService,Calibri,Helvetica,sans-serif;font-size:12pt;color:rgb(0,0,0)"> There is also a chapter all about flow networks on the Strategies web page:</div> <div style="font-family:Aptos,Aptos_EmbeddedFont,Aptos_MSFontService,Calibri,Helvetica,sans-serif;font-size:12pt;color:rgb(0,0,0)"> <br> </div> <div style="font-family:Aptos,Aptos_EmbeddedFont,Aptos_MSFontService,Calibri,Helvetica,sans-serif;font-size:12pt;color:rgb(0,0,0)"> <a href="http://contrasting.onebuilding.org/Strategies/Index.html" id="m_4699208878548327058LPlnk659891" target="_blank">http://contrasting.onebuilding.org/Strategies/Index.html</a></div> <div style="font-family:Aptos,Aptos_EmbeddedFont,Aptos_MSFontService,Calibri,Helvetica,sans-serif;font-size:12pt;color:rgb(0,0,0)"> <br> </div> <div style="font-family:Aptos,Aptos_EmbeddedFont,Aptos_MSFontService,Calibri,Helvetica,sans-serif;font-size:12pt;color:rgb(0,0,0)"> Regards, Jon Hand</div> <div id="m_4699208878548327058appendonsend"></div> <hr style="display:inline-block;width:98%"> <div id="m_4699208878548327058divRplyFwdMsg" dir="ltr"><font face="Calibri, sans-serif" style="font-size:11pt" color="#000000"><b>From:</b> <a href="mailto:esp-r-bounces@lists.strath.ac.uk" target="_blank">esp-r-bounces@lists.strath.ac.uk</a> <<a href="mailto:esp-r-bounces@lists.strath.ac.uk" target="_blank">esp-r-bounces@lists.strath.ac.uk</a>> on behalf of Clodoaldo Carvalho Filho <<a href="mailto:clodoaldo@ufc.br" target="_blank">clodoaldo@ufc.br</a>><br> <b>Sent:</b> 01 October 2023 19:54<br> <b>To:</b> <a href="mailto:esp-r@lists.strath.ac.uk" target="_blank">esp-r@lists.strath.ac.uk</a> <<a href="mailto:esp-r@lists.strath.ac.uk" target="_blank">esp-r@lists.strath.ac.uk</a>><br> <b>Subject:</b> [esp-r] Air flow network simulation without building and plant</font> <div> </div> </div> <div> <div dir="ltr">Hi you all,<br> <br> I need to configure and simulate a simple supply ventilation system. The system has a fan connected to the zone by a supply grill (local pressure loss), and the zone is connected to Exhaust by an exhaust grill (another local pressure loss).<br> <br> I am trying to do it in ESP-r, but I am experiencing some difficulty configuring the air flow network (afn) in enet and simulating it without building and plant in mfs. The afn has 4 nodes, 3 components and 6 connections (config file attached).<br> <br> enet crashes every time I try to change "i cross-sectional area (m^2)" in X11 interface and returns the following:<br> <br> At line 221 of file netwedit.F<br> Fortran runtime error: End of record<br> <br> Error termination. Backtrace:<br> #0 0x7fc546e23960 in ???<br> #1 0x7fc546e244d9 in ???<br> #2 0x7fc546e2510f in ???<br> #3 0x7fc547077360 in ???<br> #4 0x7fc54708422c in ???<br> #5 0x7fc54707ab84 in ???<br> #6 0x7fc54707ae05 in ???<br> #7 0x562913fcb789 in ???<br> #8 0x562913f7a360 in ???<br> #9 0x562913f5a7be in ???<br> #10 0x7fc546a29d8f in __libc_start_call_main<br> at ../sysdeps/nptl/libc_start_call_main.h:58<br> #11 0appreciatedx7fc546a29e3f in __libc_start_main_impl<br> at ../csu/libc-start.c:392<br> #12 0x562913f5a8a4 in ???<br> #13 0xffffffffffffffff in ???<br> <br> I am not sure the afn configuration is consistent with what mfs needs to run ok. The pressures calculated at the internal nodes are zero and mass flows at connections have different values (one of them is zero) when it should be equal. Why?<br> <br> Is there an example of a mass flow network without building and plant in ESP-r training directory?<br> <br> I am using the Network tool of ESP-r V13.3.16 of 1 June 2023, built on<br> <br> Platform - x86_64:Linux:6.2.0-33-generic<br> Compilers - gcc/g++/gfortran<br> Graphics library - X11<br> XML output - Supported<br> <br> Any clue to help me succeed in simulating this afn will be appreciated.<br> <br> Best regards,<br clear="all"> <div> <div dir="ltr"> <div dir="ltr"> <div dir="ltr"> <div> <div> <div> <div><br> </div> <div>Clodoaldo.<br> </div> <div><b><br> </b></div> <div><b>Prof. Clodoaldo de O. Carvalho Filho, Dr.</b><br> </div> <span>Universidade Federal do Ceará</span><br> Depto. de Engenharia Mecânica<br> </div> Lab. de Eficiência Energética no Conforto Ambiental - Coordenador<br> </div> ASHRAE Fortaleza Student Branch - Advisor<br> </div> <div> <div><br> </div> </div> </div> </div> </div> </div> </div> </div> </div> </div></blockquote></div>