| Author | Message | |||
     jayanta mukherjee (neo) Junior Member Username: neo Post Number: 3 Registered: 05-2005 |
Hi! I want to solve the following two coupled equations dx[k*dx(Temp)] + dy[k*dy(Temp)] + Q = 0 dx[C*dx(Voltg)] + dy[C*dy(Voltg)] = 0 where K is the thermal conductivity and C is the electrical conductivity. these two equations are coupled via the Heat Source Density(Q), where Q=[C*{[dx(Voltg)]^2 + [dy(Voltg)]^2}]. Now, my actual problem solves this equation in a multilayer system with more than 10 layers. The problem I am having with FlexPDE 4 is that I am not able to specify 'Q' the way I have written above. Kindly tell me the proper way of specifying Q, and where to do it. I will be grateful if you can give me an example with 2 layers with different K and Q. You can choose arbitrary BC’s. I will be eagerly waiting for your reply. Best Regards Jayanta Mukherjee | |||
| Robert G. Nelson (rgnelson) Moderator Username: rgnelson Post Number: 360 Registered: 06-2003 |
The FlexPDE User Guide contains a long section on setting up 3D problems, including the definition of parameters that vary by layer. The Samples folder also contains many 3D problems with layer-specific parameter definitions. See, for example, "Samples | Misc | 3d_Domains | 3D_Extrusion_Spec.pde". Your form for Q should be no problem. Just include the definition of Q in the DEFINITIONS section (after the definition of C, so it can be treated properly). You have not said what exactly you mean by "not able to specify Q". Parsing errors should be self-explanatory. What does FlexPDE tell you about the way you tried to do it? What behavior of FlexPDE makes you "not able"? | |||
| jayanta mukherjee (neo) Member Username: neo Post Number: 4 Registered: 05-2005 |
thanks the problem is that I want to specify Q within each layer. Aslo there are two layers wher Q is just a number. Please guide me how to handle this situation. | |||
| Robert G. Nelson (rgnelson) Moderator Username: rgnelson Post Number: 361 Registered: 06-2003 |
If you were to read the documentation suggested in my previous posting, specifically the User Guide, you would see the following (try it some time): ------------------ In our 2D problem, we specified the conductivity of the blob inside the REGION definition for the blob, and that continues to be the technique in 3D. The difference now is that we must also specify the LAYER to which the definition applies. We do this with a LAYER qualification clause: REGION 2 'blob' { the embedded blob } LAYER 'Can' K = 0.001 START 'ring' (R,0) ARC(CENTER=0,0) ANGLE=360 TO FINISH Without the LAYER qualification clause, the definition would apply to all layers lying above region 2 of the base plane. Here, the presence of the parameter definition inside a REGION and qualified by a LAYER selects a specific 3D compartment to which the specification applies. -------- The documentation also says other things that may be of interest in regard to your problem. | |||
| jayanta mukherjee (neo) Member Username: neo Post Number: 5 Registered: 05-2005 |
Thanks for the reply. My problem is 2D, and i am getting the following error messege . Kindly tell me what it means. "Obsolete form in version 4" each equation must be tagged with a variable '<variable>'. Kindly tell me the correct way of specifying the equations.I am attaching my .pde file Best Regards Jayanta Mukherjee
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| jayanta mukherjee (neo) Member Username: neo Post Number: 6 Registered: 05-2005 |
I could sort out the above error. thanks for the help. I will come back here if I get any more errors. Best Regards Jayanta Mukherjee |
electrothermal