sunfluidh:new_numerical_methods_setup_namelist
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Ci-dessous, les différences entre deux révisions de la page.
Les deux révisions précédentesRévision précédenteProchaine révision | Révision précédente | ||
sunfluidh:new_numerical_methods_setup_namelist [2017/09/28 18:13] – [Simulation control] yann | sunfluidh:new_numerical_methods_setup_namelist [2018/05/29 15:06] (Version actuelle) – [Poisson_NumericalMethod] witko | ||
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- | ==== Simulation control ===== | ||
- | We here resort to a specific namelist named " | ||
- | We specify here some parameters in order to define the numerical time step as well as stop criteria and recording rates related to backup and check files. | ||
- | Two examples are given. | ||
- | The first one corresponds to a simulation starting at t= 0 with a variable time step. | ||
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- | The second example corresponds to a restart of the previous simulation with a uniform time step. | ||
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- | For more information on this data set, [[sunfluidh: | ||
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- | <note important> | ||
- | Keep in mind the time step must be chosen with caution because it can generate numerical instabilities when it is too much large. The numerical stability depends on the property of the numerical methods used for solving the conservation equations It often relies on the CFL criterion which have not to exceeded a reference value. This value depends on the numerical scheme properties as well as the computational problem. | ||
- | * For semi-implicit schemes proposed here, a maximum CFL-value about 0.5 is generally prescribed for usual computations, | ||
- | * For explicit schemes, the CFL criterion also depends on the viscous/ | ||
- | When the time-step value is constant, the user can verify if the CFL criterion is respected by checking regularly the file checkcalc_xxxxx.d | ||
- | </ |
sunfluidh/new_numerical_methods_setup_namelist.1506615222.txt.gz · Dernière modification : 2017/09/28 18:13 de yann