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doc:user:integration:general:mim_tim

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doc:user:integration:general:mim_tim [2014/10/08 14:50] – jorisdoc:user:integration:general:mim_tim [2024/07/16 10:15] (current) – papeleux
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-====== Mechanical and thermal iterations manager ======+====== Managing N.-R. Iterations ======
  
 Mechanical iterations parameters are imposed by functions associated to ''metafor.getMechanicalIterationManager()'', when thermal iterations parameters are imposed by functions associated to  ''metafor.getThermalIterationManager()''. Mechanical iterations parameters are imposed by functions associated to ''metafor.getMechanicalIterationManager()'', when thermal iterations parameters are imposed by functions associated to  ''metafor.getThermalIterationManager()''.
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     mim.setConstrainedDofsVAComputationMethod(VACMeth)     mim.setConstrainedDofsVAComputationMethod(VACMeth)
     mim/tim.setPreviousResidualsDecreaseCriterion()     mim/tim.setPreviousResidualsDecreaseCriterion()
 +    mim/tim.setCpuDependency(cpuDep)
 +    mim/tim.setForceOneIte(bool)  
 +where ''meth'' defines the method used to compute the $Residual$.
  
-where ''meth'' defines the method used to calculate the $Residual$.+=== Method1ResidualComputation(limitNormFactor) === 
 +<note important>important : since revision 2946 Method1ResidualComputation is **not anymore** the default value</note>
  
-=== Method1RedisualComputation(limitNormFactor) === +The residual is adimensionalized by the norm of external forces and internal reactions .
- +
-The residual is adimensionalized from the norm of external forces and internal reactions (**default value**).+
 First : First :
  
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 === Method2ResidualComputation(limitNormFactor) === === Method2ResidualComputation(limitNormFactor) ===
  
-The residual is adimensionalized from the square of the norm of external forces and internal reactions. First:+The residual is adimensionalized by the square of the norm of external forces and internal reactions. First:
  
 $$Rmin = \frac{\sqrt{||FreeExternalForces||^2 + ||CstrInternalForces||^2+||CstrInertialForces||^2}}{nreac}$$ $$Rmin = \frac{\sqrt{||FreeExternalForces||^2 + ||CstrInternalForces||^2+||CstrInertialForces||^2}}{nreac}$$
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 === Method3ResidualComputation(limitNormFactor) === === Method3ResidualComputation(limitNormFactor) ===
  
-The residual is adimensionalized from the norm of external and inertial forces, and internal reactions (**value to use preferentially for thermal simulations. Careful, the user must define it**). +The residual is adimensionalized by the norm of external and inertial forces, and internal reactions (**value to use preferentially for thermal simulations. Careful, the user must define it**). 
  
 If  If 
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 $$Residual = \frac{||FreeResidual||}{ndofs*Rmin}$$ $$Residual = \frac{||FreeResidual||}{ndofs*Rmin}$$
  
-=== Method4ResidualComputation(limitNormFactor) === +=== Method4ResidualComputation(limitNormFactor) (**default value**) === 
- +<note important>important : since revision 2946 Method4ResidualComputation is the new **default value**</note> 
-This method is the same as ''Method1ResidualComputation()'' but without dividing by the number of dofs, so+This method is the same as ''Method1ResidualComputation()'' but without dividing by the number of dofs nor nreac, so
  
 $$Rmin = ||FreeExternalForces|| + ||CstrInternalForces||+||CstrInertialForces|| $$ $$Rmin = ||FreeExternalForces|| + ||CstrInternalForces||+||CstrInertialForces|| $$
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 | ''lsp1'' |  1.0  | accuracy that the line-search residual must reach  | | ''lsp1'' |  1.0  | accuracy that the line-search residual must reach  |
 | ''lsp2'' |  1.E-8  | stop criterion when the line search parameter is not updated enough  | | ''lsp2'' |  1.E-8  | stop criterion when the line search parameter is not updated enough  |
-| ''predMeth'' |  ''EXTRAPOLATION_DEFAULT''  | ''EXTRAPOLATION_DEFAULT'' = Extrapolation of the scheme by default (for example method to calculate the displacement predictor by Newmark formula in the case of  [[doc:user:integration:scheme:dynimpl#la_famille_alpha-generalisee|alpha-generalized scheme]])  | +| ''predMeth'' |  ''EXTRAPOLATION_DEFAULT''  | ''EXTRAPOLATION_DEFAULT'' = Extrapolation of the scheme by default (for example method to compute the displacement predictor by Newmark formula in the case of  [[doc:user:integration:scheme:dynimpl#la_famille_alpha-generalisee|alpha-generalized scheme]])  | 
-|              |                        | ''EXTRAPOLATION_MRUA'' = method to calculate the displacement predictor by MRUA formula (for now only possible for [[doc:user:integration:scheme:dynimpl#la_famille_alpha-generalisee|alpha-generalized algorithms]]) |+|              |                        | ''EXTRAPOLATION_MRUA'' = method to compute the displacement predictor by MRUA formula (for now only possible for [[doc:user:integration:scheme:dynimpl#la_famille_alpha-generalisee|alpha-generalized algorithms]]) |
 |              |                        | ''EXTRAPOLATION_ZERO'' = New positions are equal to the old ones, speed (and acceleration for dynamic schemes) equal to zero (for now only possible for  [[doc:user:integration:scheme:quasistatique|quasi-static algorithms]] and [[doc:user:integration:scheme:dynimpl#la_famille_alpha-generalisee|alpha-generalized algorithms]]) . | |              |                        | ''EXTRAPOLATION_ZERO'' = New positions are equal to the old ones, speed (and acceleration for dynamic schemes) equal to zero (for now only possible for  [[doc:user:integration:scheme:quasistatique|quasi-static algorithms]] and [[doc:user:integration:scheme:dynimpl#la_famille_alpha-generalisee|alpha-generalized algorithms]]) . |
 | ''VACMeth'' | ''VAC_SCHEMECONSISTANT'' | ''VAC_SCHEMECONSISTANT'' : Calculation of speed and acceleration with Newmark formula |  | ''VACMeth'' | ''VAC_SCHEMECONSISTANT'' | ''VAC_SCHEMECONSISTANT'' : Calculation of speed and acceleration with Newmark formula | 
-|             | | ''VAC_BACKWARDEULER'' : Calculation of speed and acceleration using Backward Euler (to stabilize Newmark with dofs with a non zero fixed displacement. see JPP's thesis pg VIII.28) |+|             | | ''VAC_BACKWARDEULER'' : Calculation of speed and acceleration using Backward Euler (to stabilize Newmark with dofs with a non zero fixed displacement. See JPP's thesis pg VIII.28) | 
 +| ''cpuDep'' | ''False'' | Specify if the criterion for updating the stiffness matrix (irea > 1) depends on the User CPU time. (Metafor Version > 2422). |  
 +| ''forceOneIte'' | ''False'' | If True, Force the resolution of at least one iteration (mechanical or thermal according to the iteration manager even if the tolerance is allready met at iteration 0. |
    
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