Comparison of simplified techniques for solving selected coupled electroheat problems

Abstract

Purpose The purpose of this paper is to compare different reduced-order models for models of control of induction brazing process. In the presented application, the problem is to reconstruct temperature at the points of interests (hot spots) from information measured at accessible places. Design/methodology/approach The paper describes the process of induction brazing. It presents the full field model and evaluates the possibilities for obtaining reduced models for temperature estimation. The primary attention is paid to the model based on proper orthogonal decomposition (POD). Findings The paper shows that for the given application, it is possible to find low-order estimator. In the examined linear case, the best estimator was created using POD reduced model together with the linear Kalman filter. Research limitations/implications The authors are aware of two main limitations of the presented study: material properties are considered linear, which is not a completely realistic assumption. However, if strong coupling and nonlinear material parameters are considered, the model becomes unsolvable. The process and measurement uncertainties are not considered. Originality/value The paper deals with POD of multi-physics 3 D application of induction brazing. The paper compares 11 different methods for temperature estimator design.

FEM Based Preliminary Design Optimization in Case of Large Power Transformers

“…Artap is an optimization framework developed within University of West Bohemia [24]. Written in Python, it is mainly inspired by projects OpenMDAO [29] and Platypus [30].Ārtap aims to provide an extensive infrastructure for robust design optimization problems [31][32][33] in a simple, user friendly way. Moreover, it contains an integrated FEM solver Agros-Suite [34], which is used in this paper for the FEM calculations.…”

Dual-mixed hp-version axisymmetric shell finite element using NURBS mid-surface interpolation

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Artap: Robust Design Optimization Framework for Engineering Applications

“…The numerical solution of this equation system -without any simplification -on an appropriate mesh leads to millions of equations, which cannot be used for real-time control. There are many possibilities to create a reduced order model with Artap, two possibilities is shown in this paper [6], [7]. Firstly, the problem is formulated as a parameter identification task.…”