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Provozní parametry a charakteristiky aktuátorů s dilatačním prvkem
Doležel, Ivo ; Karban, P. ; Ulrych, B. ; Barglik, J. ; Pantelyat, M. ; Matyukhin, Y. ; Gontarowskiy, P.
In specific applications one needs actuators characterized by very high forces at small shifts. As actuators of classical constructions mostly cannot satisfy these requirements, the authors designed another arrangement with an inductively heated dilatation element. But huge mechanical strains and stresses of thermoelastic origin acting in its structural parts could lead to its damage or destruction. The paper deals with mathematical modeling of the device that is solved numerically in the combined formulation (while the electromagnetic field is solved independently, the thermal and thermoelastic effects are solved in the hard-coupled formulation). The algorithm is illustrated on a typical example whose results are discussed.
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Techniky zpracování tuhých a tekutých kovů založené na elektromagnetické indukci
Doležel, Ivo ; Šolín, Pavel ; Musil, Ladislav ; Ulrych, B. ; Karban, P. ; Barglik, J.
A lot of up-to-date industrial technologies associated with treatment of solid and liquid metals are based on thermal and force effects of electromagnetic field. The fundamental process is induction heating of metals that precedes a number of consequent operations such as tempering, drying, melting, stirring, hardening, hot pressing etc. The paper summarizes physical essence of the above processes (that usually represent complex coupled problems) and presents their mathematical and computer models as well as possible methods of their solutions.
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Jev "zamrzlého pole" v elektricky vodivých médiích, řešený prostředky klasické elektrodynamiky
Doležel, Ivo ; Karban, P. ; Mayer, D. ; Ulrych, B.
The concept "frozen field" is often used in association with behavior of strongly electrically conductive media. Being introduced in astrophysics the phenomenon consists in drift of magnetic field by electrically well conductive medium (plasma or ionized mixture of gas and dust particles) that moves due to some primary mechanism not immediately associated with this magnetic field. This paper presents the description of the effect by means of classical electrodynamics in nonrelativistic medium and its solution in an integral formulation.
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Posuvný indukční ohřev a související jevy v kvazi-sdružené formulaci
Karban, P. ; Ulrych, B. ; Doležel, Ivo
The paper deals with quasi-coupled numerical solution of the problem of induction heating and associated phenomena in 2D axisymmetric arrangements. The process of heating is modeled by a special algorithm respecting the temperature dependencies of various material properties and (when necessary) time variable boundary conditions. The algorithm fully developed by the authors is illustrated on an example of continual induction hardening
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Polařský a obvodový model dávkovače zinku
Musil, Ladislav ; Praglowska-Gorczynska, Z.
Electromagnetic feeders of molten metals are used in some industrial technologies, particularly for accurate dosing. Mathematical model of such devices represents a complicated coupled task characterised by interaction of electromagnetic, temperature and flow fields. The paper deals with numerical computation of several important quantities of the device providing its circuit parameters
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