I'm hesitating to refer to this as an element with internal nodes. The 
displacement degrees of freedom would still be interpolated with bilinear 
shape functions but the gauss point degrees of freedom are not interpolated 
over the element. They are independent of the other gauss point degrees of 
freedom. 

On Wednesday, March 7, 2018 at 10:46:12 AM UTC-5, Jonathan Russ wrote:
>
> Some people refer to this as an element with internal nodes.
>
> On Wednesday, March 7, 2018 at 10:43:13 AM UTC-5, Jonathan Russ wrote:
>>
>> Hi Bruno -
>>
>> Thank you for your fast reply. I'm sorry I'm not doing a great job of 
>> explaining this. Here is an example from elasticity that illustrates what I 
>> would like:
>> In this case there are displacement degrees of freedom at the nodes but 
>> the stress is a quantity typically derived from the displacements. However, 
>> one could make the stress an independent degree of freedom at the gauss 
>> points. 
>>
>> So, in the element there would be displacement degrees of freedom at the 
>> nodes and stress degrees of freedom at the gauss points. Does this make 
>> sense?
>>
>> Thank you again,
>> Jonathan
>>
>> On Wednesday, March 7, 2018 at 10:30:44 AM UTC-5, Bruno Turcksin wrote:
>>>
>>> Jonathan,
>>>
>>> On Wednesday, March 7, 2018 at 10:20:44 AM UTC-5, Jonathan Russ wrote:
>>>>
>>>> Is there a FiniteElement in deal.II that allows the addition of degrees 
>>>> of freedom at gauss points so that the DoFHandler object also manages 
>>>> them? 
>>>> For example, I would like to have just a standard Lagrangian finite 
>>>> element 
>>>> interpolated with the plain bilinear shape functions for nodal degrees of 
>>>> freedom but I also have a single degree of freedom at each gauss point 
>>>> within the element (and, consequently, residual equations at each gauss 
>>>> point in each element). Is this possible in deal.II to have degrees of 
>>>> freedom not associated with nodes?
>>>>
>>> I am not sure I understand your question. Do you want Lagrangian FE 
>>> where you pick yourself the node? If that is the case then you can use this 
>>> constructor 
>>> <http://dealii.org/developer/doxygen/deal.II/classFE__Q.html#a32ccedfe518cfe3fca02cdddf9e664f6>
>>>  
>>> Of course the order of the finite element will depend on the number of 
>>> point in you quadrature. Or do you want to  evaluate your finite element at 
>>> some quadrature points?
>>>
>>> Best,
>>>
>>> Bruno
>>>
>>

-- 
The deal.II project is located at http://www.dealii.org/
For mailing list/forum options, see 
https://groups.google.com/d/forum/dealii?hl=en
--- 
You received this message because you are subscribed to the Google Groups 
"deal.II User Group" group.
To unsubscribe from this group and stop receiving emails from it, send an email 
to dealii+unsubscr...@googlegroups.com.
For more options, visit https://groups.google.com/d/optout.

Reply via email to