|
|
Magnetostrictive materials for mechatronics
Rusková, Miroslava ; Kovář, Jiří (referee) ; Hadaš, Zdeněk (advisor)
The aim of this work is to outline and use or application of magnetostrictive materials and possibilities of mathematical modeling their behavior. Magnetostrictive is the physical character of the material, occurs in the most ferromagnetic materials and leads to many effects. Magnetostrictive materials are more often used to in various branches of engineering.
|
|
|
Surface acoustic wave filter
Tichý, Jakub ; Dědková, Jarmila (referee) ; Raida, Zbyněk (advisor)
The theoretical part of this thesis deals with principles and characteristics of the surface acoustic wave filter. It explained the principle of magnetostriction and piezoelectric effect, which uses a filter. In the practical part in the program Comsol Multiphysics are made three simple models of SAW filter. Some modes are founded and are compared to previously known results. In the next phase of project is further studied using the parametric analysis. In the last phase of project is applied global optimization PSO at admittance characteristic from simple 2D structure. The results are compared with the commercially produced devices.
|
|
|
Magnetostriction vibration power generator
Šumpelová, Jana ; Singule, Vladislav (referee) ; Hadaš, Zdeněk (advisor)
This thesis deals with the idea of energy harvesting from mechanical vibration. It describes the magnetostrictive principle as a possibility to obtain an electrical energy. It is about a generator made of a beam with Terfenol-D material and a coil. The model of this device is created in Matlab/Simulink and FEMM application. For various values of measured vibration, these methods are then compared. In FEMM, you can improve energy gain by modeling of various environmental conditions and with using of another materials (e.g. by adding of permanent magnets). The outcome of the this thesis expresses the ability to harvest the energy with designed magnetostrictive generator compared to the already created models of the piezoelectric and electromagnetic generator. Based on these results, it is possible to determine which generator is more suitable for particular application.
|
|
|
Matematické modelování magnetosriktních látek
Vermach, Lukáš ; Kružík, Martin (advisor) ; Zeman, Jan (referee)
4 Title: Mathematical modeling of magnetostrictive materials Author: Lukáš Vermach Department: Mathematical Institute of Charles University Advisor: Priv.-Doz. Dr. habil. RNDr. Martin Kružík Ph.D., Institute of Information Theory and Automation, Academy of Sciences of the Czech Republic Advisor's e-mail address: kruzik@utia.cas.cz Abstract In the present work we introduce an isotermic mathematical model of ferromagnetic shape memory alloys (FSMAs). FSMAs are a special class of magnetostrictive materials, i.e. materials which deform their shape on account of external magnetic field or which change magnetization as a consequence of strain. This property originates from phase transformations that occur within the material when being exposed to external loading. First, the stationary model of FSMA is formulated. The thermodynamical potential is composed (Helmholz free energy) and its non-quasiconvexity is discussed. The quasicon- vexification is performed via the relaxation theory, i.e. quasiconvex envelope construction. For such a model the existence theory is built. Then, taking advantage of the stationary case the evolutionary model is developed. The attention is drawn to hysteresis, which arises from energy dissipation. The time discretization leads to a sequence of hysteresis-modified stationary problems (the...
|
|
|
Magnetostriction vibration power generator
Šumpelová, Jana ; Singule, Vladislav (referee) ; Hadaš, Zdeněk (advisor)
This thesis deals with the idea of energy harvesting from mechanical vibration. It describes the magnetostrictive principle as a possibility to obtain an electrical energy. It is about a generator made of a beam with Terfenol-D material and a coil. The model of this device is created in Matlab/Simulink and FEMM application. For various values of measured vibration, these methods are then compared. In FEMM, you can improve energy gain by modeling of various environmental conditions and with using of another materials (e.g. by adding of permanent magnets). The outcome of the this thesis expresses the ability to harvest the energy with designed magnetostrictive generator compared to the already created models of the piezoelectric and electromagnetic generator. Based on these results, it is possible to determine which generator is more suitable for particular application.
|
|
|
Matematické modelování magnetosriktních látek
Vermach, Lukáš ; Kružík, Martin (advisor) ; Zeman, Jan (referee)
4 Title: Mathematical modeling of magnetostrictive materials Author: Lukáš Vermach Department: Mathematical Institute of Charles University Advisor: Priv.-Doz. Dr. habil. RNDr. Martin Kružík Ph.D., Institute of Information Theory and Automation, Academy of Sciences of the Czech Republic Advisor's e-mail address: kruzik@utia.cas.cz Abstract In the present work we introduce an isotermic mathematical model of ferromagnetic shape memory alloys (FSMAs). FSMAs are a special class of magnetostrictive materials, i.e. materials which deform their shape on account of external magnetic field or which change magnetization as a consequence of strain. This property originates from phase transformations that occur within the material when being exposed to external loading. First, the stationary model of FSMA is formulated. The thermodynamical potential is composed (Helmholz free energy) and its non-quasiconvexity is discussed. The quasicon- vexification is performed via the relaxation theory, i.e. quasiconvex envelope construction. For such a model the existence theory is built. Then, taking advantage of the stationary case the evolutionary model is developed. The attention is drawn to hysteresis, which arises from energy dissipation. The time discretization leads to a sequence of hysteresis-modified stationary problems (the...
|
|
|
Magnetostrictive materials for mechatronics
Rusková, Miroslava ; Kovář, Jiří (referee) ; Hadaš, Zdeněk (advisor)
The aim of this work is to outline and use or application of magnetostrictive materials and possibilities of mathematical modeling their behavior. Magnetostrictive is the physical character of the material, occurs in the most ferromagnetic materials and leads to many effects. Magnetostrictive materials are more often used to in various branches of engineering.
|
|
|
Surface acoustic wave filter
Tichý, Jakub ; Dědková, Jarmila (referee) ; Raida, Zbyněk (advisor)
The theoretical part of this thesis deals with principles and characteristics of the surface acoustic wave filter. It explained the principle of magnetostriction and piezoelectric effect, which uses a filter. In the practical part in the program Comsol Multiphysics are made three simple models of SAW filter. Some modes are founded and are compared to previously known results. In the next phase of project is further studied using the parametric analysis. In the last phase of project is applied global optimization PSO at admittance characteristic from simple 2D structure. The results are compared with the commercially produced devices.
|
guest ::
