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laws:vmvp [2024/11/29 15:46]
carlos [VMVP: viscoplasticity]
laws:vmvp [2024/11/29 15:53] (current)
carlos [VMVP: formulation generalities]
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 $\Phi = J_{2}(\underline{\tilde{\sigma}}-\underline{\mathbb{X}})-\sigma_{y}-R \leq 0$\\ $\Phi = J_{2}(\underline{\tilde{\sigma}}-\underline{\mathbb{X}})-\sigma_{y}-R \leq 0$\\
  
-where:\\ +>where: 
-* $\sigma_{y}$ is the yield stress of the material.\\ +>* $\sigma_{y}$ is the yield stress of the material. 
-* $R$ is the isotorpic hardening, calculated as the Voce iso. hardening law:\\ +>* $R$ is the isotorpic hardening, calculated as the Voce iso. hardening law: 
-$\dot{R} = -b\cdot (Q-R)\cdot \dot{p} ​ \hspace{1cm} -> \hspace{1cm} R(p)=Q\cdot (1-\exp(-b\cdot p))$\\ where $p$ is the equivalent plastic strain $(-)$, and $\dot{p}$ is the equivalent plastic strain rate $(s^{-1})$\\+>$\hspace{1cm} ​\dot{R} = -b\cdot (Q-R)\cdot \dot{p} ​ \hspace{1cm} -> \hspace{1cm} R(p)=Q\cdot (1-\exp(-b\cdot p))$\\ where $p$ is the equivalent plastic strain $(-)$, and $\dot{p}$ is the equivalent plastic strain rate $(s^{-1})$\\
  
 Inheriting the classical Chaboche-type formulation,​ the backstress tensor $\underline{\mathbb{X}}$ is calculated as the sum of a total of $nAF$ user-defined Armstrong-Frederick (AF) backstress equations. \\ Inheriting the classical Chaboche-type formulation,​ the backstress tensor $\underline{\mathbb{X}}$ is calculated as the sum of a total of $nAF$ user-defined Armstrong-Frederick (AF) backstress equations. \\
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 >> · $\underline{\tilde{\sigma}}_{k+1}=\underline{\sigma}_{k+1} \cdot (1-D_{k})^{-1}$ >> · $\underline{\tilde{\sigma}}_{k+1}=\underline{\sigma}_{k+1} \cdot (1-D_{k})^{-1}$
 >> · $D_{k+1}=f \Bigl( \underline{\sigma}_{k+1},​ D_{k},... \Bigr)$\\ >> · $D_{k+1}=f \Bigl( \underline{\sigma}_{k+1},​ D_{k},... \Bigr)$\\
-> **dam_type = 3** Fully-coupled damage.+> **dam_type = 2** Fully-coupled damage.
 >In this final case, the damage equations are included within the big Jacobian unknown set of equations, and are solved together with all the system in an implicit manner. It is a time-consuming and computationally heavy approach, where: >In this final case, the damage equations are included within the big Jacobian unknown set of equations, and are solved together with all the system in an implicit manner. It is a time-consuming and computationally heavy approach, where:
 >> · $\underline{\tilde{\sigma}}_{k+1}=\underline{\sigma}_{k+1} \cdot (1-D_{k+1})^{-1}$ >> · $\underline{\tilde{\sigma}}_{k+1}=\underline{\sigma}_{k+1} \cdot (1-D_{k+1})^{-1}$
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 ^Line 01; format (2I5, 60A1)^^ ^Line 01; format (2I5, 60A1)^^
 |IL|Law number| |IL|Law number|
-|ITYPE| ​271|+|ITYPE| ​282|
 |COMMENT| Any comment (up to 60 characters) that will be reproduced on the output listing| |COMMENT| Any comment (up to 60 characters) that will be reproduced on the output listing|
  
laws/vmvp.1732891572.txt.gz · Last modified: 2024/11/29 15:46 by carlos