Boundary conditions in models of power plant components under thermal loading

• Autorzy: Okrajni J. , Twardawa M.
• Języki publikacji: EN

Abstrakty

EN

Purpose: The main purpose of the work is the description of conditions of fatigue process of power plant components working under mechanical and thermal loading. The work focuses on the chosen component characteristics. The issue of influence of the heat transfer conditions on the component surface on stresses changes in time has been discussed. Design/methodology/approach: The FEM modelling method has been used to describe the behaviour of the chosen component. The models have been validated on the basis of temperature measurements during operation period. Findings: It has been shown that the determination of the effects induced by unsteady conditions of start-up and shut-down of installations requires application of unconventional methods of research and analysis of their results. In such a case, a methodology can be applied consisting in combining the methods of computer modelling of temperature fields with temperature measurements in selected points of the component. Research limitations/implications: The presented analysis is the part of the complex investigation method which main purpose is increasing the accuracy of the thermo-mechanical fatigue process description. In such situation the investigations curried out in the work give the model approach and data for the comparison the real behaviour with the predictions. However the work is focused only on the chosen component and chosen characteristics of loading. Practical implications: The method of the chosen component behaviour analysis used in the paper could be useful in the practical cases when the real components mechanical behaviour would be analysed and their fatigue life would be assessed. Originality/value: The main value of this paper is the own method of the mechanical behaviour analysis of the power plant components. This method includes FEM modelling and assumption that the heat transfer coefficient should be treated as dependent on time. The material stress-strain behaviour has been treated as the local phenomenon that could be modelled.

Słowa kluczowe

EN

applied mechanics; power plants; heat transfer; fatigue

PL

mechanika stosowana; elektrownia; wymiana ciepła; zmęczenie

• Wydawca: International OCSCO World Press
• Czasopismo: Archives of Materials Science and Engineering
• Rocznik: 2013
• Tom: Vol. 62, nr 1
• Strony: 28--35
• Opis fizyczny: Bibliogr. 25 poz.

Twórcy

autor

Okrajni J.

• Faculty of Materials Engineering and Metallurgy, Silesian University of Technology, ul. Krasińskiego 8, 40-019 Katowice, Poland

autor

Twardawa M.

• RAFAKO S.A., ul. Łąkowa 33, 47-400 Racibórz, Poland

Bibliografia

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