Sven Friedel
                                                                                                                                                    COMSOL Employee
                                                         
                            
                                                                                                                                                
                         
                                                
    
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                                                Posted:
                            
                                1 decade ago                            
                            
                                2015年3月23日 GMT+8 22:07                            
                        
                        
                                                
                            HI Bartu,
have a look here
https://ch.comsol.com/model/piezoresistive-pressure-sensor-12629
Best regards,
Sven                        
                                                
                                                                                                            
                                             
                                            
                            
                                                                                        
                                Nagi Elabbasi
                                                                                                                                                    Facebook Reality Labs
                                                         
                            
                         
                                                
    
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                                                Posted:
                            
                                1 decade ago                            
                            
                                2015年3月24日 GMT+8 00:52                            
                        
                        
                                                    Hi Bartu,
I think COMSOL is very well suited for this problem, and can handle the different length scales easily. Here is an idea that, if applicable, will simplify your models.
In most cases a strain gauge does not affect the strain state of the underlying structure so it does not need to be explicitly modeled. By the same reasoning, if you need to model the electro-mechanical behavior of the strain gauge you do not need the full structure. You can just find the stress-strain field at the strain gauge location and apply it to a separate strain gauge model. That way you simplify your models and avoid the different length scales.
Nagi Elabbasi
Veryst Engineering                                                
                                                
                            Hi Bartu,
I think COMSOL is very well suited for this problem, and can handle the different length scales easily. Here is an idea that, if applicable, will simplify your models.
In most cases a strain gauge does not affect the strain state of the underlying structure so it does not need to be explicitly modeled. By the same reasoning, if you need to model the electro-mechanical behavior of the strain gauge you do not need the full structure. You can just find the stress-strain field at the strain gauge location and apply it to a separate strain gauge model. That way you simplify your models and avoid the different length scales.
Nagi Elabbasi
Veryst Engineering                        
                                                
                                                                                                            
                                             
                                            
                                                
    
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                                                Posted:
                            
                                1 decade ago                            
                            
                                2015年3月24日 GMT+8 01:25                            
                        
                        
                                                    Hi Sven and Nagi,
thank you very much for your replies. Those are really helpful.
In the meantime, I have also decided to simulate the adhesion behaviour between the layers. I have a sandwich-like structure that will experience numerous bending modes during operation. So, I want to check and quantify whether the bonded layers debond or not.
In my research I came across an analytical model called "Cohesive Zone Model". However, I am not entirely sure if it is the best analytical model for this kind of situation.
Are you familiar with some tutorials or analytical model regarding this adhesion issue?
Thanks,
Bartu                                                
                                                
                            Hi Sven and Nagi,
thank you very much for your replies. Those are really helpful.
In the meantime, I have also decided to simulate the adhesion behaviour between the layers. I have a sandwich-like structure that will experience numerous bending modes during operation. So, I want to check and quantify whether the bonded layers debond or not.
In my research I came across an analytical model called "Cohesive Zone Model". However, I am not entirely sure if it is the best analytical model for this kind of situation.
Are you familiar with some tutorials or analytical model regarding this adhesion issue?
Thanks,
Bartu                        
                                                
                                                                                                            
                                             
                                            
                            
                                                                                        
                                Nagi Elabbasi
                                                                                                                                                    Facebook Reality Labs
                                                         
                            
                         
                                                
    
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                                                Posted:
                            
                                1 decade ago                            
                            
                                2015年3月24日 GMT+8 01:36                            
                        
                        
                                                    You're welcome.
In general the Cohesive Zone Model is a suitable approach to simulate debonding. Here is a COMSOL Model Gallery example showing how to implement it: 
www.comsol.com/model/mixed-mode-debonding-of-a-laminated-composite-19961. You also need to measure several properties that characterize the bond strength.
Nagi Elabbasi
Veryst Engineering                                                
 
                                                
                            You're welcome.
In general the Cohesive Zone Model is a suitable approach to simulate debonding. Here is a COMSOL Model Gallery example showing how to implement it: http://www.comsol.com/model/mixed-mode-debonding-of-a-laminated-composite-19961. You also need to measure several properties that characterize the bond strength.
Nagi Elabbasi
Veryst Engineering                        
                                                
                                                                                                            
                                             
                                            
                                                
    
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                                                Posted:
                            
                                1 decade ago                            
                            
                                2015年3月24日 GMT+8 04:13                            
                        
                        
                                                    Thanks Nagi,
are there any other easy-to-apply analytical models (other than CZM) that you have experience with?
Bartu                                                
                                                
                            Thanks Nagi,
are there any other easy-to-apply analytical models (other than CZM) that you have experience with?
Bartu                        
                                                
                                                                                                            
                                             
                        
                        
                            
                                                                                        
                                Jeff Hiller
                                                                                                                                                    COMSOL Employee
                                                         
                            
                                                                                                                                                
                         
                                                
    
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                                                Posted:
                            
                                9 years ago                            
                            
                                2016年7月2日 GMT+8 02:57                            
                        
                        
                                                    On CZM: this is the approach implemented in the adhesion/decohesion capabilities added into the Structural MEchanics Module at version 5.2a, see 
www.comsol.com/release/5.2a/structural-mechanics-module .
Best,
Jeff                                                
 
                                                
                            On CZM: this is the approach implemented in the adhesion/decohesion capabilities added into the Structural MEchanics Module at version 5.2a, see https://www.comsol.com/release/5.2a/structural-mechanics-module .
Best,
Jeff