Transient Behaviour of Annular Catalytic Converters

• Autorzy: Budzianowski W.
• Języki publikacji: EN

Abstrakty

EN

This paper is a contribution to the development of catalytic converters for combustion of lean gaseous fuels. The results of the investigation of the behaviour of such converters may enable further improvement, prediction and control of transient ignition/extinction phenomena. It was observed that in an annular double-layer catalytic converter the low value of substrate's thermal conductivity accelerated ignition and retarded extinction. This was attributed to transient warm-up behaviour i.e. exhibition of S-shaped axial temperature profiles. The converter with the low value of the heat capacity of a substrate located especially at the inlet exhibited accelerated ignition whereas retarded extinction was attained in the converter with the higher value of heat capacity located especially at the inlet. Miniaturization of a converter accelerated mass and heat transfer which took positive effect on accelerated ignition and retarded extinction. In a proposed recuperated converter a step-increase in inlet fuel concentration initially resulted in intensive energy transfer to exhausts and energy accumulation into a converter structure. Similarly decreasing a fuel calorific value initially resulted in the heating of gas with energy accumulated in a converter structure and further, as the inlet became cold, in intensive exhausts energy recuperation. A recuperated converter exhibited the overtemperature phenomenon of low intensity. The investigated recuperated converter exhibited ability to transfer short-time inlet fluctuations counteracting to extinction or to destructive overheating of catalysts.

Słowa kluczowe

EN

catalytic converters; combustion; annular converters

• Wydawca: Komitet Termodynamiki i Spalania PAN
• Czasopismo: Archivum Combustionis
• Rocznik: 2008
• Tom: Vol. 28 nr 3-4
• Strony: 231--246
• Opis fizyczny: Bibliogr. 18 poz., rys.

Twórcy

autor

Budzianowski W.

• Division of Chemical and Biochemical Processes, Wroclaw University of Technology Norwida 4/6, 50-373 Wroclaw, Poland,

Bibliografia

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