<div dir="ltr"><div>Hi all, </div><div><br></div><div>I am modeling a hot water system with a tempering valve (step 1 : a fraction of the cold flow is sent to the heat source to be heated up, step 2 : the other is mixed with the resulting hot flow). However, in my case, I can't use the built-in component "tempering valve". Indeed, another hot flow is added between step 1 and 2 so the component equations are not valid anymore. Yet, I haven't found any satisfactory method to handle this. Here is what I have tried out : </div>
<div><br></div><div style>- The flow diverter parameter Y (step 1) is set by user-provided equations (equations box), function of temperatures and flow rates in the loop + set temperature</div><div style><br></div><div style>
--> convergence problems </div><div style><br></div><div style>- The flow diverter parameter Y (step 1) is set by a controller (PID or iterative). However, when the set temperature is reached, tracking error tends to 0 and so does the control signal (connected directly to the valve opening Y). It is not the solution at a given time step. Controller output should not be linked direcly to the valve opening (but to its derivative I guess). </div>
<div style><br></div><div style>--> stability problems (it oscillated around the set temperature)</div><div style><br></div><div style><br></div><div style>Do you have any idea how to solve this simple problem? </div><div style>
<br></div><div style><br></div><div style>Please let me know if I am not clear enough. </div><div style><br></div><div style><br></div><div style><br></div><div style>Thanks in advance,</div><div style><br></div><div style>
<br></div><div style><br></div><div style>Regards,</div>
<div><br></div><br clear="all"><div><div dir="ltr"><div align="left" style="font-family:'Times New Roman'"><font face="Arial"><strong><em>Damien CASETTA</em></strong></font></div><div align="left" style="font-family:'Times New Roman'">
<font face="Arial"><strong><em>INSA Lyon / Génie Energétique et Environnement</em></strong></font></div><div align="left" style="font-family:'Times New Roman'"><font face="Arial"><strong><em>ENERTECH / Cabinet SIDLER</em></strong></font></div>
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