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Statické charakteristiky konstrukčních částí řiditelného termoelastického aktuátoru
Doležel, Ivo ; Kotlan, V. ; Ulrych, B.
The paper deals with one of the basic conditions of practical employment of finely controllable thermoelastic actuators – problems of the static characteristics of its individual structural parts. It contains the formulation of the principle of such thermoelastic actuators, description of its components (a dilatation element heated by induction, auxiliary electromagnetic actuators, and self-locking friction clutches) and their mathematical models. Briefly discussed are also their corresponding computer models making use of the finite element method. The crucial point of the work consists in the presentation of the results – static characteristics of the considered structural parts of the controlled thermoelastic actuators.
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Zpracování informací získaných z termochromních kapalných krystalů
Tesař, Václav ; Randa, Zdeněk
Thermochromic liquid crystals respond to local changes of temperature by varying the colour of reflected light. Their use in experiments with anisothermal fluid flows seems to be simple - just taking pictures of the colours on the walls exposed to the fluid flow. However, practical extraction of quantitative informationfrom the pictures is not straightforward and brings a number of pitfalls. Unfortunately, these details are generally not found in available literature since most authors mention these practical procedure aspects very briefly, if at all. The present paper concentrates on these practical steps following them on a practicalexample of an investigation of an impinging jet, presenting the experience acquired in such investigations.
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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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