Hi Abhishek,

Thanks for the update, glad to hear we are producing correct results on that front.

Regarding the linear stability; can you share your XML file? It might just be that the base flow needs to be properly imposed in the appropriate scalar -- we probably haven't taken scalar fields into account yet in the setup.

Thanks,

Dave

> On 6 Feb 2018, at 13:20, Abhishek Kumar <abhishek.kir@gmail.com> wrote:
>
> Dear David,
>
> Thanks for your answer. Now, I got it.
>
> You would be happy to know that the Rayleigh-Benard convection (RBC) solver is working properly with Nektar++. I have tested the solver and also did a benchmark with Clever & Busse JFM 1974 for the Nusselt number calculation. There is an excellent agreement.
>
> Now, I am trying to do the direct linear stability for RBC. But, I find there is a problem with the base flow addition for the buoyant scalar. I have reported this issue on the forum. Could you kindly also check this issue.
>
> Again, thanks for your response.
>
> With regards
> Abhishek
>
>
>
> On Mon, Feb 5, 2018 at 5:15 PM, David Moxey <D.Moxey@exeter.ac.uk> wrote:
> Hi Abhishek,
>
> These define the various choice of basis functions; the first is the modified C^0 basis that's defined in Karniadakis & Sherwin. The other two are Lagrange basis functions: the first is a choice with the number of quadrature points as one higher than the number of points; the other is where they are equal (i.e. the collocated basis with diagonal mass matrix).
>
> I believe all of those basis functions should work fine for 2D elements. For 3D, Lagrange only presently works for hex elements, whereas the C^0 has full support for hex/tet/prism/pyramid.
>
> Hope that helps,
>
> Dave
>
> > On 1 Feb 2018, at 17:42, Abhishek Kumar <abhishek.kir@gmail.com> wrote:
> >
> > Dear friends,
> >
> > I am new to NEKTAR++.
> >
> > Can someone tell me the difference between MODIFIED, GLL_LAGRANGE, GLL_LAGRANGE_SEM expansions type?
> >
> >
> > With regards
> > Abhishek Kumar
> >
> > ---------------------------------------------------------------------------------------
> > Abhishek Kumar
> > Post Doctoral Researcher
> > Applied Mathematics Research Centre
> > Coventry University, Coventry CV15FB
> > The United Kingdom
> >
> > Email # ac7600@coventry.ac.uk, abhishek.kir@gmail.com
> > ---------------------------------------------------------------------------------------
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>
>
>
>
> --
> With regards
> Abhishek Kumar
>
> ---------------------------------------------------------------------------------------
> Abhishek Kumar
> Post Doctoral Researcher
> Applied Mathematics Research Centre
> Coventry University, Coventry CV15FB
> The United Kingdom
>
> Email # ac7600@coventry.ac.uk, abhishek.kir@gmail.com
> ---------------------------------------------------------------------------------------
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