Interface identification in magnetic fluid dynamics

In magnetic fluid dynamics appears the problem of reconstruction of free boundary between conducting fluids, e.g. in aluminum electrolysis cells. We have investigated how the interface between two fluids of different conductivity of a highly simplified model of an aluminum electrolysis cell could be reconstructed by means of external magnetic field measurements using simple genetic algorithm

Application of genetic algorithms to an inverse field problem in magnetic fluid dynamics

The purpose of the present work is to study whether genetic algorithms can solve an inverse field problem in magnetic fluid dynamics (MFD) efficiently. We have investigated how the interface between two fluids of different conductivity in a highly simplified model of an aluminum electrolysis cell can be reconstructed by means of external magnetic field measurements. The knowledge of the interface deformation can be used to prevent undesired instabilities in aluminum reduction cells

Modelling of Seebeck effect in electron beam deep welding of dissimilar metals

Purpose – The purpose of this paper is to present a 3D model of deep welding of dissimilar metals and to show how to model the electron beam deflection due to thermoelectric fields caused by temperature gradients in some dissimilar metals (Seebeck effect). Design/methodology/approach – A 3D thermoelectric and heat conduction model is used to estimate the deflection of the electron beam used during welding of dissimilar metals. A weak coupling between analysed fields is assembled. Additionally, the influence of the deflection on the calculated fields was not taken into account. The problem is solved using a finite element method. Findings – It is possible to model Seebeck effect in a relative simple way using the finite element approach. Originality/value – The paper presents a detailed description of modelling procedure of a complex coupled field problem

Comparison of defect detection limits in Lorentz force eddy current testing and classical eddy current testing

Lorentz force eddy current testing (LET) is a motion-induced eddy current testing method in the framework of nondestructive testing. In this study, we address the question of how this method is classified in comparison with a commercial eddy current testing (ECT) measurement device ELOTEST N300 in combination with the probe PKA48 from Rohmann GmbH. Therefore, measurements using both methods are performed and evaluated. Based on the measurement results, the corresponding defect detection limits, i.e., up to which depth the defect can be detected, are determined and discussed. For that reason, the excitation frequency spectrum of the induced eddy currents in the case of LET is considered

In situ impedance measurements on postmortem porcine brain

The paper presents an experimental study where the distinctness of grey and white matter of an in situ postmortem porcine brain by impedance measurements is investigated. Experimental conditions that would allow to conduct the same experiment on in vivo human brain tissue are replicated