Effect of fouling deposit shape on its thermal resistance

• Autorzy: Skiepko T.
• Języki publikacji: EN

Abstrakty

EN

The paper presents the results of computational analysis concerning the effect of non-uniformity in the fouling layer shape deposited onto the outer surface of a circular tube on the thermal resistance of the deposit. Taken into considerations modes of heat transfer from a hot gas to the outer surface of the fouling layer are: either by pure convection or radiation, and by both these modes combined. A fluid flowing inside the tube exchanges heat by only convection at constant transfer coefficient. The boundary weighted residual approach based on the variational principle and implementation of the Trefftz method have been applied in analysis of the problem under study. The main outcomes from the paper are results of systematic numerical experiments, illustrating influence of 2D fouling deposit shape (at the outer periphery of a circular tube) on its thermal resistance. In turn, the study demonstrates a significant effect of the deposit shape that when it is in the form of a non-uniform layer can reduce the fouling resistance by order of 35%-80% compared to the deposit of the uniform thickness around the tube periphery.

Słowa kluczowe

EN

boiler tube; Fouling deposit; Mitigation; thermal resistance

PL

odporność cieplna; osłabienie; rury kotłowe

• Wydawca: Wydawnictwo Instytutu Maszyn Przepływowych PAN ; Komitet Termodynamiki i Spalania PAN
• Czasopismo: Archives of Thermodynamics
• Rocznik: 2009
• Tom: Vol. 30, no. 1
• Strony: 3--26
• Opis fizyczny: Bibliogr. 15 poz.,Rys., tab., wykr., wz.,

Twórcy

autor

Skiepko T.

• Faculty of Mechanics, Białystok, Technical University, Wiejska 45C, 15-351 Białystok, Poland,

Bibliografia

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