Ivar KJELBERG
                                                                                                                                                    COMSOL Multiphysics(r) fan, retired, former "Senior Expert" at CSEM SA (CH)
                                                         
                            
                         
                                                
    
        Please login with a confirmed email address before reporting spam
     
    
 
                                                Posted:
                            
                                1 decade ago                            
                            
                                10 feb 2012, 15:05 GMT-5                            
                        
                        
                                                    Hi
I'm not by my COMSOL WS so I cannot take a quick look, but one thing that is important with Eddy current simulations, is to resolve correctly the region where the Eddy current develop. This is often in the "skin layer" at a metallic boundary. Therefore you need dense mesh perpendicular to the skin depth decay, and lateral w.r.t the Eddy current loop you expect (model B field dependent). I would recommend to se a "boundary mesh" on the conductive side, and adapt its size to resolve correctly the skin depth, or better 2x the skin depth
Then if you have an AC field, do not forget for the ACDC hypothese to be correct (else consider RF) that your wavelength in the mteril is much greater than the model
--
Good luck
Ivar                                                
                                                
                            Hi
I'm not by my COMSOL WS so I cannot take a quick look, but one thing that is important with Eddy current simulations, is to resolve correctly the region where the Eddy current develop. This is often in the "skin layer" at a metallic boundary. Therefore you need dense mesh perpendicular to the skin depth decay, and lateral w.r.t the Eddy current loop you expect (model B field dependent). I would recommend to se a "boundary mesh" on the conductive side, and adapt its size to resolve correctly the skin depth, or better 2x the skin depth
Then if you have an AC field, do not forget for the ACDC hypothese to be correct (else consider RF) that your wavelength in the mteril is much greater than the model
--
Good luck
Ivar                        
                                                
                                                                                                            
                                             
                                            
                            
                                                                                        
                                Joao Vicente Goncalves Rocha
                                                                                                                                                 
                            
                         
                                                
    
        Please login with a confirmed email address before reporting spam
     
    
 
                                                Posted:
                            
                                1 decade ago                            
                            
                                13 feb 2012, 06:59 GMT-5                            
                        
                        
                                                    Ty for your response,
I´m having bad times trying to simulate this model. I need to see the impedance plan variation when the coil pass on a very small notch in the tube wall. Two issues here:
1 - The superficie is a tube, so is much more trickier to mesh this;
2 - The notch width is 85 microns, so I´m encountering more difficults to mesh it to...
Some help in this issues would be appreciated.
[]´s,
JV                                                
                                                
                            Ty for your response,
I´m having bad times trying to simulate this model. I need to see the impedance plan variation when the coil pass on a very small notch in the tube wall. Two issues here:
1 - The superficie is a tube, so is much more trickier to mesh this;
2 - The notch width is 85 microns, so I´m encountering more difficults to mesh it to...
Some help in this issues would be appreciated.
[]´s,
JV                        
                                                
                                                                                                            
                                             
                        
                        
                            
                                                                                        
                                Ivar KJELBERG
                                                                                                                                                    COMSOL Multiphysics(r) fan, retired, former "Senior Expert" at CSEM SA (CH)
                                                         
                            
                         
                                                
    
        Please login with a confirmed email address before reporting spam
     
    
 
                                                Posted:
                            
                                1 decade ago                            
                            
                                13 feb 2012, 08:15 GMT-5                            
                        
                        
                                                    Hi
very large size ratios are difficult to mesh, often one need to cut up the bulk material a few times, check the FORUM for meshing, there are several discussion there on "how to better mesh". In anycase be sure you have a fine enough mesh for your induced Eddy current region
--
Good luck
Ivar                                                
                                                
                            Hi
very large size ratios are difficult to mesh, often one need to cut up the bulk material a few times, check the FORUM for meshing, there are several discussion there on "how to better mesh". In anycase be sure you have a fine enough mesh for your induced Eddy current region
--
Good luck
Ivar