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

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Abhishek Kumar
Post Doctoral Researcher
Applied Mathematics Research Centre
Coventry University, Coventry CV15FB
The United Kingdom

Email # ac7600@coventry.ac.ukabhishek.kir@gmail.com
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