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MKP 3D MODELOVÁNÍ TEPELNÝCH DĚJŮ TLUMÍCÍCH PRVKŮ S TERMO-MECHANICKOU VAZBOU
Pešek, Luděk ; Šulc, Petr
The COMSOL code based on weak formulation of PDE's problem was used for solution of thermo-mechanical interaction in pre-pressed rubber segment used for resilient elements of the composed tram wheels. For computational time efficiency the structural and heat field are decomposed and the balance of heat power density and dissipation power density realizes the coupling. The dissipation power is computed according to the assumed proportional damping model. The results of thermo-mechanical processes for press and shear deformations under static pre-pressed and cyclic dynamic loading are presented and analyzed.
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FE model termomechanické interakce pryžového bloku při cyklickém dynamickém zatížení
Pešek, Luděk ; Šulc, Petr
The COMSOL code based on weak formulation of PDE’s problem was used at a solution of feedback thermo-mechanical interaction in pre-pressed rubber block used for resilient elements of the composed tram wheels. The structural motion and heat conduction equations are solved interactively as time dependent problems. The equality of heat energy density and dissipation energy density realizes the coupling between the equations. The dissipation energy density is computed according to the assumed proportional damping model. In the paper the results of thermo-mechanical processes in cases of a plane strain and 3D space deformation under static pre-pressed and cyclic dynamic loading are presented and analyzed.
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FEM modeling of thermo-mechanical interaction in rubber block
Pešek, Luděk ; Půst, Ladislav ; Šulc, Petr
The FEMLAB code based on weak formulation of PDE’s problem was used at a solution of feedback thermo-mechanical interaction in damping bodies by finite element method. In our approach structural motion and heat conduction equations are solved interactively as time dependent problems. The conservative energy law, i.e. equality of heat energy density and dissipation energy density, realizes the coupling between the equations. The dissipation energy density is computed according to the assumed damping model. In the contribution the results, such as temperature versus strain distribution, of thermo-mechanical processes in case of a plane strain deformation under static compression and cyclic dynamic loading concerning mechanical energy lost modeled as proportional damping, heat generation, heat transfer between rubber and outer steel parts, cooling problem and changing stiffness and damping coef.
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FE heat conduction modeling of Rubber segment at mechanical harmonic excitation
Šulc, Petr ; Pešek, Luděk
This contribution deals with the numerical finite element modeling of rubber sample temperature field at the harmonic mechanical loading when the heat generated by absorbed mechanical energy is substituted by the constant heat rate input. As the study case a segment of the rubber-damped railway tram wheel was chosen. This segment was experimentally tested and the results were used for tuning the parameters of the FE model of heat conduction and transfer in program ANSYS 6.1.
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Privatizace městského bytového fondu v Havlíčkově Brodu
Šulc, Petr ; Krebs, Vojtěch (advisor) ; Hermann, Tomáš (referee)
Cílem diplomové práce je přiblížit čtenáři vývoj a základní charakteristiky koncepce bytové politiky ČR a dále pak způsob jakým vznikl městský bytový fond. Čtenáři této práce by měli pochopit právní koncepci privatizace obecních bytů a její aplikaci na konkrétním případu privatizace bytového fondu v Havlíčkově Brodu, kterou zde uvádím včetně jejího zhodnocení. V poslední kapitole se budu věnovat vyhodnocení výsledků dotazníků, které jsem získal na základě výběrového šetření od dotazovaného spektra lidí, jichž se privatizace týkala. Na jeho základě ověřím pomocí statistické metody Chí-kvadrat test logické hypotézy stanovené na základních ekonomických úvahách a všeobecně známých skutečnostech.
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