Re: [deal.II] Accessing a particular boundary in one-dimensional case

On 3/13/20 5:34 PM, Krishnakumar Gopalakrishnan wrote: Looking at step-7 and adapting it a little bit, does the following code look reasonable to mark the boundary ID of the left edge as '1' for later setting its flux? for (const auto &cell : triangulation.cell_iterators

[deal.II] Accessing a particular boundary in one-dimensional case

For a one-dimensional unit domain (0,1), if one needs to set non-homogenous Neumann BC at a particular end of the domain (say the left end, x=0), Looking at step-7 and adapting it a little bit, does the following code look reasonable to mark the boundary ID of the left edge as '1' for later set

Re: [deal.II] Linearizing a non-linear diffusion equation by using value from previous-time step for the non-linear part (Rothe method)

On 3/13/20 2:49 PM, Krishnakumar Gopalakrishnan wrote: * /Yes, it's a good step. But it implies that you get a restriction on the time step size. / Does that become severe even if I use the present time-step for all other terms? In the \nabla ( D(u) u) term, I will replace only D(u) with

Re: [deal.II] Linearizing a non-linear diffusion equation by using value from previous-time step for the non-linear part (Rothe method)

- *Yes, it's a good step. But it implies that you get a restriction on the time step size. * Does that become severe even if I use the present time-step for all other terms? In the \nabla ( D(u) u) term, I will replace only D(u) with the previous time-steps and retain the u^{n} to b

Re: [deal.II] Linearizing a non-linear diffusion equation by using value from previous-time step for the non-linear part (Rothe method)

On 3/13/20 12:59 PM, Krishnakumar Gopalakrishnan wrote: I have a non-linear diffusion equation of the form du/dt = \nabla.( D(u) \grad u) The non-linearity appears because of the dependence of the diffusion coefficient on the solution. When discretising by the Rothe method, applying backward

Re: [deal.II] Initial guidance/starting point for solving a non-linear diffusion equation with double neumann BCs

1. Unlike Step-7, I have Neumann-only BCs. In my prior experience with the FD and FV methods, this is a difficult problem. Is there any specific advice that can help me with this? But step-7 also has Neumann boundary conditions. What is different in your case? That you *only* have Neumann b

[deal.II] Linearizing a non-linear diffusion equation by using value from previous-time step for the non-linear part (Rothe method)

I have a non-linear diffusion equation of the form du/dt = \nabla.( D(u) \grad u) The non-linearity appears because of the dependence of the diffusion coefficient on the solution. When discretising by the Rothe method, applying backward Euler method in the strictest sense: (u^n - u^{n-1})/k^

Re: [deal.II] Regarding a change in step-26 initial condition

Dear Prof. Bangerth, Thank you very much for the explanation. Interpolation of the initial condition works pretty well! Thanks & Regards Pawan On Fri, Mar 13, 2020 at 3:55 PM Wolfgang Bangerth wrote: > On 3/13/20 6:08 AM, Pawan Kumar wrote: > > > > To incorporate adaptive mesh refinement afte

Re: [deal.II] Regarding a change in step-26 initial condition

On 3/13/20 6:08 AM, Pawan Kumar wrote: To incorporate adaptive mesh refinement after each time steps in my ongoing work, I am trying to make follwoing small changes in step-26: i. Initial condition ii. A rectangular domain iii. Homogeneous Neumann BC. But I am getting some errors(negative

Re: [deal.II] Initial guidance/starting point for solving a non-linear diffusion equation with double neumann BCs

Hi Daniel, Thank you for your reply. I had seen all the tutorials you mentioned. Let me further clarify some of the things in my PDE that are somewhat different from the tutorials. 1. Unlike Step-7, I have Neumann-only BCs. In my prior experience with the FD and FV methods, this is a difficult p

[deal.II] Regarding a change in step-26 initial condition

Dear all; To incorporate adaptive mesh refinement after each time steps in my ongoing work, I am trying to make follwoing small changes in step-26: i. Initial condition ii. A rectangular domain iii. Homogeneous Neumann BC. But I am getting some errors(negative values) in the obtained in

Re: [deal.II] Compiling error in a poroelastic problem similar to step-21

Thank you very much for your help, Wolfgang. Following your advice, I have changed the definition of DispRightHandSide from Function to TensorFunction and the subsequent lines and the code have compiled successfully. Again, thanks for your help. Best, Teresa. On Thursday, March 12, 202

Re: [deal.II] Deal.II on Docker

The examples you are using are likely looking for deal.II 9.2.pre. Try changing the makefile, and see if that works. :-) Luca > Il giorno 13 mar 2020, alle ore 02:47, Robert Kopp > ha scritto: > >  > After some false starts, I was able to use deal.II on Ubuntu 18.04 by > installing it from