Parameter Identification of a Finite Viscoplastic Material Model using different Deterministic Optimization Methods

PAMM ◽  
2003 ◽  
Vol 2 (1) ◽  
pp. 525-526
Author(s):  
A. Rieger ◽  
G. Scheday ◽  
C. Miehe
Author(s):  
Chitra Dangwal ◽  
Marcello Canova

Abstract Predicting the chemical and physical processes occurring in Lithium-ion cells with high-fidelity electrochemical models is today a critical requirement to accelerate the design and optimization of battery packs for automotive and aerospace applications. One of the common issues associated with electrochemical models is the complexity of parameter identification, particularly when relying only on experimental data obtained via non-invasive techniques. This paper presents a novel approach to improve the common methods of parameter calibration that consists of matching the predicted terminal voltage to test data via optimization methods. The study is conducted for an NMC-graphite cell, modeled using a reduced order Extended Single Particle Model (ESPM). The proposed approach relies on using a large-scale Particle Swarm Optimization (PSO), modified by including a term that accounts for the parameter sensitivity information, such that the rate of convergence and robustness of the algorithm to obtain a consistent solution in the presence of uncertainties in the initial conditions are significantly improved.


Author(s):  
A. Andrade-Campos

The use of optimization methods in engineering is increasing. Process and product optimization, inverse problems, shape optimization, and topology optimization are frequent problems both in industry and science communities. In this paper, an optimization framework for engineering inverse problems such as the parameter identification and the shape optimization problems is presented. It inherits the large experience gain in such problems by the SiDoLo code and adds the latest developments in direct search optimization algorithms. User subroutines in Sdl allow the program to be customized for particular applications. Several applications in parameter identification and shape optimization topics using Sdl Lab are presented. The use of commercial and non-commercial (in-house) Finite Element Method codes to evaluate the objective function can be achieved using the interfaces pre-developed in Sdl Lab. The shape optimization problem of the determination of the initial geometry of a blank on a deep drawing square cup problem is analysed and discussed. The main goal of this problem is to determine the optimum shape of the initial blank in order to save latter trimming operations and costs.


Author(s):  
Swagatam Paul ◽  
Snehasish Bhattacharjee ◽  
Sanjib Kumar Acharyya ◽  
Prasanta Sahoo

Fracture toughness of ferritic steel in the ductile-to-brittle transition zone is scattered and probabilistic owing to embrittlement. Use of master curve along with the reference temperature ( T0) adopted in ASTM E-1921 is widely accepted for characterization of this embrittlement. Reference temperature is a measure of embrittlement in the temperature scale. Factors affecting fracture toughness like geometry and loading rate are expected to influence the reference temperature. In the present study, the role of the loading rate on the reference temperature for 20MnMoNi55 steel is assessed experimentally using compact tension C(T) and three-point bend (TPB) specimens. Finite element simulation of tests at different loading rates and cryogenic temperature are carried out using a suitable viscoplastic material model that incorporates flow characteristics of the material for varying displacement rates and cryogenic temperatures. Results from simulation studies are compared with experimental ones.


1991 ◽  
Vol 58 (2) ◽  
pp. 499-506 ◽  
Author(s):  
M. J. Saran ◽  
R. H. Wagoner

A formulation for finite element simulation of highly nonlinear problems including friction and contact with arbitrarily shaped rigid surfaces is proposed (CFS approach), prompted by difficulties in robust and accurate simulations of industrial forming processes. Nonlinearities are caused by large strains, plastic flow, and complex boundary conditions with frictional contact. In Part I the theoretical basis is described and the appropriate numerical algorithm is derived. The complete set of the governing relations, comprising equilibrium and interfacial equations, is appropriately linearized; resulting in a consistent tangent operator of the Newton-Raphson algorithm. In Part II, as a numerical verification, plane-strain sheet-forming processes are analyzed using a rigid-viscoplastic material model. Results are presented and discussed for test problems and for complex simulation of reverse drawing by concave tools.


2016 ◽  
Vol 138 (4) ◽  
Author(s):  
Richard A. Barrett ◽  
Eimear M. O'Hara ◽  
Padraic E. O'Donoghue ◽  
Sean B. Leen

This paper presents the high-temperature low-cycle fatigue (HTLCF) behavior of a precipitate strengthened 9Cr martensitic steel, MarBN, designed to provide enhanced creep strength and precipitate stability at high temperature. The strain-controlled test program addresses the cyclic effects of strain-rate and strain-range at 600 °C, as well as tensile stress-relaxation response. A recently developed unified cyclic viscoplastic material model is implemented to characterize the complex cyclic and relaxation plasticity response, including cyclic softening and kinematic hardening effects. The measured response is compared to that of P91 steel, a current power plant material, and shows enhanced cyclic strength relative to P91.


2007 ◽  
Vol 561-565 ◽  
pp. 1869-1874
Author(s):  
Quan Lin Jin ◽  
Yan Shu Zhang

A hybrid global optimization method combining the Real-coded genetic algorithm and some classical local optimization methods is constructed and applied to develop a special program for parameter identification. Finally, the parameter identification for both 26Cr2Ni4MoV steel and AZ31D magnesium alloy is carried out by using the program. A comparison of deformation test and numerical simulation shows that the parameter identification and the obtained two sets of material parameters are all available.


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