[Nek5000-users] Nek5000 pertubation mode

[Paul Fischer]

great!


On Wed, 3 Jun 2009, Antonios Monokrousos wrote:

> Dear Paul,
> I tested the new version also with my case (blasius BL) and it works
> fine (with de-aliasing)!
> Many thanks!
> Antonios
>
> Paul Fischer wrote:
>>
>>
>> Dear Antonios,
>>
>> If you can try the current version of the svn repo,
>> the perturbation code should now work with dealiasing
>> turned on.
>>
>> Moreover, you can automatically turn off the base-flow
>> evolution by setting the number of perturbation modes
>> (p31 in the .rea file) to be < 0.  Thus, p31=-1 would
>> give one perturbation mode, no base flow evolution.
>> The base flow would be defined, e.g., in the useric.
>>
>> I include an example case in the attached tarfile,
>> Orr-Sommerfeld evolution.
>>
>> Paul
>>
>>
>> On Wed, 3 Jun 2009, Antonios Monokrousos wrote:
>>
>>> Dear Paul,
>>> I finally found what the problem with my case was. It was the
>>> de-aliasing. The problem appears first in the subroutine advabp (file
>>> perturb.f) where subroutine convop is called (file navier1.f). It seems
>>> that de-aliasing is not working for the pertubation/linear mode (?) When
>>> I deactivate the de-aliasing (from the rea file) the result looks
>>> correct.
>>> I tested it also with channel flow and it was the same problem: In
>>> pertubation mode, with de-aliasing a forcing appears in a few specific
>>> elements. I haven't been able to understand exactly why this happens but
>>> I suspect it has to do with the size of the arrays.
>>> Best regards
>>> Antonios
>>>
>>>
>>> --
>