Lappeenranta University of Technology Acta Universitatis Lappeenrantaensis 570 Samuli Kallio Modeling and Parameter Estimation of Double-Star Permanent Magnet Synchronous Machines Lappeenranta 2014 68 p. ISBN 978-952-265-563-9 ISBN 978-952-265-564-6 (PDF) ISSN-L 1456-4491, ISSN 1456-4491 The power rating of wind turbines is constantly increasing; however, keeping the voltage rating at the low-v...

We propose a computational method with no ad hoc empirical parameters to determine the elastic properties of multiphase composites of complex geometries by numerically solving the stress–strain relationships in heterogeneous materials. First the randommicrostructure of the multiphase composites is reproduced in our model by the random generation-growth method. Then a high-efficiency lattice Bol...

Region-based level set segmentation is a paradigm for the automatic segmentation of brain tumor image. Unfortunately, region-based segmentation, which is relied on the intensity difference of different regions, has been of limited used in presence of complex background. Algorithm based on calculating the variational energy of the Chan-Vese model without the length. The multiphase level set form...

In o_shore petroleum engineering, the multiphase production technique has become a standard method for the exploitation of marginal fields. The multiphase production technology consists in conveying untreated wellhead e_uent through a single pipeline either to an existing processing platform or to onshore processing facilities. Transient phenomena can be caused by changes in the inlet flow-rate...

We consider a hyperbolic system of three conservation laws in one space variable. The system is a model for fluid flow allowing phase transitions; in this case the state variables are the specific volume, the velocity and the mass density fraction of the vapor in the fluid. For a class of initial data having large total variation we prove the global existence of solutions to the Cauchy problem....

The ability to accurately predict the consequences of hazardous fluid release is dependent on three things: the knowledge of the modeler, the quality of the model that is used, and the quality of the input parameters. One of the most difficult problems in consequence modeling is the prediction of post-release multiphase behavior, especially when a multicomponent mixture is involved. Releases fr...

Reliance on multiphase fluid-dynamics models, which are developed with relatively limited experimental data, requires a quantitative assessment of the solution variability due to the approximations. In this paper, uncertainty in the Eulerian multiphase boiling model in the Nphase-CMFD code is assessed in the context of the DEBORA test case and the CRUD problem. The models under consideration ar...

color metallography is a useful method for characterizing microstructures of steels with multiple phases. in this paper, application of three different color etching techniques for a bainitic-martensitic steel is reported. comparisons between the results showed that 10% na2s2o5 aqueous solution was the best etchant for distinguishing martensite, bainite and ferrite phases. the obtained microgra...

The dependence relation between the macroscopic effective property and the microstructure of interpenetrating multiphase composites is investigated in this paper. The effective elastic moduli of such composites cannot be calculated from conventional micromechanics methods based on Eshelby s tensor because an interpenetrating phase cannot be extracted as dispersed inclusions. Employing the conce...

In this paper we present a new model framework for studying vascular tumour growth, in which the blood vessel density is explicitly considered. Our continuum model comprises conservation of mass and momentum equations for the volume fractions of tumour cells, extracellular material and blood vessels. We include the physical mechanisms that we believe to be dominant, namely birth and death of tu...