Hello Irene Elliot
                            
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                                Mads Herring Jensen
                                                                                                                                                    COMSOL Employee
                                                         
                            
                                                                                                                                                
                         
                                                
    
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                                                Posted:
                            
                                9 years ago                            
                            
                                12.01.2017, 16:52 GMT-5                            
                        
                        
                                                    Hi Irene
Setting up a transmission loss problem in the time domain through a periodic structure is very difficult, if the incidence is not normal to the surface. In the frequency domain you can use the Floquet periodicity condition. Another challenge is setting up good radiation conditions at both sides of the system.
I would recommend to model this in the frequency domain and then use the transfer function to predict the time domain behavior.
There are several tutorials on this, here is one:
www.comsol.com/model/acoustic-transmission-loss-through-periodic-elastic-structures-1974
Best regards
Mads                                                
                            Hi Irene
Setting up a transmission loss problem in the time domain through a periodic structure is very difficult, if the incidence is not normal to the surface. In the frequency domain you can use the Floquet periodicity condition. Another challenge is setting up good radiation conditions at both sides of the system.
I would recommend to model this in the frequency domain and then use the transfer function to predict the time domain behavior.
There are several tutorials on this, here is one:
https://www.comsol.com/model/acoustic-transmission-loss-through-periodic-elastic-structures-1974
Best regards
Mads                        
                                                
                                                                                                            
                                             
                        
                        
                                                
    
        Please login with a confirmed email address before reporting spam
     
    
 
                                                Posted:
                            
                                9 years ago                            
                            
                                30.01.2017, 01:17 GMT-5                            
                        
                        
                                                    
Hi Irene
Setting up a transmission loss problem in the time domain through a periodic structure is very difficult, if the incidence is not normal to the surface. In the frequency domain you can use the Floquet periodicity condition. Another challenge is setting up good radiation conditions at both sides of the system.
I would recommend to model this in the frequency domain and then use the transfer function to predict the time domain behavior.
There are several tutorials on this, here is one:
www.comsol.com/model/acoustic-transmission-loss-through-periodic-elastic-structures-1974
Best regards
Mads
Hi Mads,
Floquet periodic boundary condition does not work with normal incidence wave?
--
Regards,
Linus Ang                                                
 
                                                
                            [QUOTE]
Hi Irene
Setting up a transmission loss problem in the time domain through a periodic structure is very difficult, if the incidence is not normal to the surface. In the frequency domain you can use the Floquet periodicity condition. Another challenge is setting up good radiation conditions at both sides of the system.
I would recommend to model this in the frequency domain and then use the transfer function to predict the time domain behavior.
There are several tutorials on this, here is one:
https://www.comsol.com/model/acoustic-transmission-loss-through-periodic-elastic-structures-1974
Best regards
Mads
[/QUOTE]
Hi Mads,
Floquet periodic boundary condition does not work with normal incidence wave?
--
Regards,
Linus Ang