FEAP User Forum

FEAP => General questions => Topic started by: Colin McAuliffe on July 17, 2012, 10:08:31 AM

Title: Robin Boundary Conditions
Post by: Colin McAuliffe on July 17, 2012, 10:08:31 AM
Hello all,

Does FEAP have commands to define Robin BC's such as surface convection and elastic boundaries?

Thanks
Colin
Title: Re: Robin Boundary Conditions
Post by: FEAP_Admin on July 17, 2012, 11:09:43 AM
For simple elastic boundaries you could use elastic springs (point elements) or nodal springs.  For more complex BC a user element is probably the best way to go.
Title: Re: Robin Boundary Conditions
Post by: Prof. S. Govindjee on July 17, 2012, 11:19:20 AM
Colin,
  Have a look at http://www.ce.berkeley.edu/~sanjay/FEAP/lysmer.html for an example user element for a 'complex' boundary condition:  d[traction]/dt + M v = 0 where traction = sigma^T n, M is a matrix, and v = velocity.