| 摘要 |
FIELD: power engineering; devices and methods for creation of high temperatures on surface of ceramic checker during burning of hydrocarbon fuels. SUBSTANCE: in its construction, the ceramic infra-red radiator includes ceramic (transparent for gas) cylindrical checker with passage inside it for admission and distribution of mixture of gaseous fuel. Volumetric ceramic checker of infra-red radiator consists of coaxial alternating non-corrugated cylinders 1 and corrugated cylinders 2 made from catalyst- activated ceramic. The passages in body of volumetric ceramic checker through which gas escapes and where combustion is accomplished have regular zigzag form. Radial removal of combustion products provides for extended time of presence of reaction mixture inside volumetric checker where surface combustion takes place, thus ensuring better and smooth heating of volumetric checker and reducing losses of heat with combustion products and increasing linear velocities at inlet of central passage increasing the heat transfer coefficient which makes it possible to cool the beginning of central passage directly by gas reaction mixture at simultaneous heating of this mixture excluding jump of flame beyond combustion zone. Presence of ferric oxide, nickel oxide and oxides of other metals contained in lattice-matrix is absolutely necessary because they are catalysts of ignition and combustion. Method of preparation of catalytically-active ceramics consists in placing the charge containing aluminium powder, plasticizer and zirconium oxide powder on metal lattice-matrix. The specimen thus prepared is dried at room temperature after which it is placed in oxidizing medium at a temperature of about 1000 to 1200 C. After heating of the specimen, binder is burnt out and aluminium powder is oxidized, i.e. self-propagating high-temperature synthesis of ceramic - aluminium oxide and oxidation of metal lattice to oxides takes place. Due to self- propagating high-temperature synthesis, strongconjugation of formed aluminium oxide with matri
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