GUI - Momentum source - Math. expression editor

Phjod · Post by **Phjod** » Sat Jan 10, 2015 4:49 pm

Hello.
Could somebody provide me with an example of usage of mathematical expression editor to fill in momentum sources (Su, dSudu, etc.)? It seems I don't understand correctly the methode and receive sustematic error in running the solver. Sorry for this first silly question...
Thanks in advance, regards, PhJ.

Post by **Erwan Le Coupanec** » Mon Jan 12, 2015 10:40 am

Hello,

The momentum source terms you can fill in the GUI are then used as follows:

$\underline{ST} = (\underline{S} + \underline{\underline{dS}}_{\underline{u}} \underline{u})|\Omega_I|$

where
$\underline{S}$ : volumic production of momentum - explicit part ( $kg/m^2/s^2$ )
$\underline{\underline{dS}}_{\underline{u}}$ : volumic production of momentum - implicit part ( $kg/m^3/s$ ).

As a first attempt, you can put the whole source term in the explicit part $\underline{S}$ .

Regards,
Erwan.

Phjod · Post by **Phjod** » Sat Jan 17, 2015 7:29 pm

Hello.
I appreciate your help.
I understand theory and concept, but all what I try to implement in the GUI - math editor - even simplest things as constant everywhere on al 6 parameters, results in solver failure with SIGSEGV... That is the reason why I ask for an example, trying therefore to locate my mistake by doing this. Initialisation is no problem, just moment source definition
Best regards,
Ph.

Post by **Yvan Fournier** » Sun Jan 18, 2015 7:35 pm

Hello,

Could you post files as per the forum recommendations to let us understand what type of error you obtain ?

Regards,

Yvan

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GUI - Momentum source - Math. expression editor

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