LUP Student Papers

LUND UNIVERSITY LIBRARIES

Thermoplasticity in topology optimization based on finite strain

(2017) In ISRN LUTFD2/TFHF-17/5221-SE(1-46) FHL820 20171
Solid Mechanics
Abstract
A thermoplastic finite strain model is used to model heat generation due to plastic work.
Isotropic hardening is used, where the mechanical dissipation acts as heat source in the heat equation. The multiplicative split of the deformation gradient makes it possible to separate plastic and elastic effects. The model is solved by using the Newmark time integration scheme with the finite element method using total Lagrangian formulation.
The model is also aimed for implementation with gradient based topology optimization
for finite strains with the objective to maximize the the plastic dissipation. The method
of moving asymptotes (MMA) is used in the optimization to make the problem convex.
The sensitivities required to form the gradient... (More)
A thermoplastic finite strain model is used to model heat generation due to plastic work.
Isotropic hardening is used, where the mechanical dissipation acts as heat source in the heat equation. The multiplicative split of the deformation gradient makes it possible to separate plastic and elastic effects. The model is solved by using the Newmark time integration scheme with the finite element method using total Lagrangian formulation.
The model is also aimed for implementation with gradient based topology optimization
for finite strains with the objective to maximize the the plastic dissipation. The method
of moving asymptotes (MMA) is used in the optimization to make the problem convex.
The sensitivities required to form the gradient is calculated using the adjoint method
where the sensitivities are derived for the thermoplastic case. Helmholtz’s partial
differential equation is used for regularization and a Heaviside filter is used to make the topology more precise. (Less)
Popular Abstract (Swedish)
Kan man låta datorn bestämma den säkraste designen för en bil? och kommer en ökning av temperaturen i det använda materialet att påverka denna design? I examensarbetet ”Thermoplasticity in topology optimization based on finite
strain” undersöks hur den genererade temperaturen vid en snabb och stor ihoptryckning av en struktur påverkar den design som ̈är bäst på att absorbera energi vid t.ex. en krock. Det visar sig att temperaturen har en avsevärd inverkan på den bästa designen.
author
supervisor
organization
course
FHL820 20171
year
type
H3 - Professional qualifications (4 Years - )
subject
keywords
FEM, topology optimization, finite deformations, thermoplasticity
publication/series
ISRN LUTFD2/TFHF-17/5221-SE(1-46)
report number
TFHF-5221
language
English
id
8922885
2017-08-17 11:21:16
date last changed
2018-01-01 04:09:20
```@misc{8922885,
abstract     = {A thermoplastic finite strain model is used to model heat generation due to plastic work.
Isotropic hardening is used, where the mechanical dissipation acts as heat source in the heat equation. The multiplicative split of the deformation gradient makes it possible to separate plastic and elastic effects. The model is solved by using the Newmark time integration scheme with the finite element method using total Lagrangian formulation.
The model is also aimed for implementation with gradient based topology optimization
for finite strains with the objective to maximize the the plastic dissipation. The method
of moving asymptotes (MMA) is used in the optimization to make the problem convex.
The sensitivities required to form the gradient is calculated using the adjoint method
where the sensitivities are derived for the thermoplastic case. Helmholtz’s partial
differential equation is used for regularization and a Heaviside filter is used to make the topology more precise.},
author       = {Engström, Anders},
keyword      = {FEM,topology optimization,finite deformations,thermoplasticity},
language     = {eng},
note         = {Student Paper},
series       = {ISRN LUTFD2/TFHF-17/5221-SE(1-46)},
title        = {Thermoplasticity in topology optimization based on finite strain},
year         = {2017},
}

```