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extrusion coupling error
Posted Dec 18, 2011, 10:13 p.m. EST Parameters, Variables, & Functions, Results & Visualization Version 4.2a 3 Replies
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I have defined a general extrusion coupling operator to obtain the dependent variable (in my heat transfer case, the temperature "T") at a boundary. the setting of the extrusion is shown in the attachment (the .PNG file ).
when i solve my model, the following error occurs. could you give me some guidance?
Failed to find consistent initial values.
Extrusion coupling operator interpolation failed for at least one point: no source point found.
Geometry: 1, Boundary: 3, Destination coordinates: [4.452806170061471e+021], [4.456088152789275e+021], [-6.161457555631103e+020], [-8.411254597429331e+020], [-9.319635436176123e+020], ...
Failed to evaluate expression.
Expression: mod1.genext1(mod1.T)
Failed to evaluate variable.
Variable: mod1.ale.vn, Defined as: ((sqrt(((0.5*M)/(mod1.genext1(mod1.T)*(R gs*pi))))*(exp(((L em*(mod1.genext1(mod1.T)-T e))/((mod1.genext1(mod1.T)*R gs)*T e)))*(Pr 0*(-(1-R fc)))))/mod1.genext1(mod1.mat1.def.rho))
Failed to evaluate expression.
Expression: d(((mod1.ale.xt free*mod1.ale.nx+mod1.ale.yt free*mod1.ale.ny-mod1.ale.vn)*test(-x lm))*(dvol),{test0})
Last time step is not converged.
Thanks for your response. Best wishes to you and your family.
FM Huang
Dec. 19th ,2011
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sorry I'm not sure what it can be, could be linked to the ALE ? Have you tried it out on a simpelr model. But I might too have missed something simple ;)
--
Good luck
Ivar
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Hi
sorry I'm not sure what it can be, could be linked to the ALE ? Have you tried it out on a simpelr model. But I might too have missed something simple ;)
--
Good luck
Ivar
Thanks sincerely for your fast response. According to your guidance, I have built a model without the ALE to check whether there is something wrong with the extrusion coupling operator. all the details are shown in the attachment. Would you do me a favor to check it and give me some guidance?
Thanks in advance for your help.
Yours
FM Huang
Dec.19th.2011
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I believe you have some confusions (or is it me?) w.r.t global and local variables, your dependent value T is a "field"
T(x,y,t) depending on the spatial and time variables, so it can not be used "globally" without some specific operation on the domain "(x,y)" and for a given time "t". You Extrusion variable TD1 is also a field it depends on TD1(x,t) but no longer for y, but TD1(0.5,t) is probably different from TD1(0.75,t) so TD1 must also be referred to w.r.t. a given domain or boundary coordinate (only x is used) and the time "t".
The post processing "global variables" are variables that are independent of the spatial coordinates, but might depend on time of any "parametric" sweep parameter, so you must apply an average, or an integration operator over a spatial element to get to a true "Global variable" that is independent of (x,y,z)
I believe you should reread the doc again, I must admit I have reread it a dozen of times, and I started to understand these differences really rather late after several re-reads ;)
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Good luck
Ivar