I probably understand that I need to add a vector force to change my right hand matrix But I am not very good at modifying this part of the content through code of Deal.ii How can mathematical knowledge be transformed into deal.ii code? So do I need to replace the original right-hand matrix on the basis of step8? Or is it enough to directly define a new point load vector? Can you give me an example on the basis of step8 for a better understanding?
Thanks, Best wishes! Nick 在2020年11月11日星期三 UTC+8 上午3:22:56<Wolfgang Bangerth> 写道： > On 11/10/20 12:11 AM, Nick Wang wrote: > > Uh, what I want to do is to use deal.ii to simulate our own model, > > Before using deal.ii , I used some numerical simulation software like > abaqus. > > However, it will be very difficult to use abaqus to simulate seepage > flow > > and multiphase coupling. > > I tried to use deal to build a simple model to deepen my understanding > of this > > software. > > So on the basis of step-8, I imported an external mesh model, > > On this basic elastic equation, I tried to add some loads to analyze the > > deformation characteristics of this model like abaqus > > Then further modify the constitutive equation, like an elastoplastic > problem... > > So I am trying to add a point load(parallel load) anywhere on the model > first > > but I don't know how to achieve it. > > Nick, > so let's say you want to add a point load at a point x0 in direction d. > That > corresponds to a vector force > \vec f(x) = \vec d * delta(x-x0) > What you then need to compute the right hand side vector for your finite > element scheme is to compute > F_i = \int_\Omega \vec phi_i(x) \cdot \vec f(x) > = \vec d \cdot \vec \phi_i(x) > > You'd implement something like this in the same way as the > VectorTools::compute_point_source_vector() does for the scalar case. The > implementation of that case can be found here: > > > https://github.com/dealii/dealii/blob/master/include/deal.II/numerics/vector_tools_point_value.templates.h#L276-L309 > > Best > W. > > -- > ------------------------------------------------------------------------ > Wolfgang Bangerth email: bang...@colostate.edu > www: http://www.math.colostate.edu/~bangerth/ > > -- 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. To view this discussion on the web visit https://groups.google.com/d/msgid/dealii/c9289f64-54f5-4d8f-8569-7d2ce5c655a8n%40googlegroups.com.
