GB825880A - Improvements relating to the production of hot gases by the burning of liquid fuel - Google Patents

Abstract

825,880. Liquid fuel burners. FRASER, R. P. Aug. 16, 1957 [Aug. 23, 1956], No. 25840/56. Class 75(1) [Also in Group XII] A burner for the partial or complete combustion of liquid fuel with the product utilized elsewhere for combustion or chemical processes or the speed of the hot jet being used for fast convection heating, moulding and heating an' article, or heating and conveying an article, comprises an atomizer wherein atomization is effected by 25 to 100% of the air stream, the air being passed through the burner with a pressure drop of less than 2 lb./ sq. in. and the atomizer having means whereby the liquid fuel and air is maintained in constant proportion, whatever the flow quantity and the burner has means whereby a portion of the partially or fully burnt combustion products from the combustion space of the burner is recirculated to the entry point of the atomized fuel and air mixture. In the form shown liquid fuel controlled by a V- notched plunger 7 passes to the bore of a tube 1 at the end 2 of which the liquid fuel issues as a lateral spray to be atomized by air discharging around the oil tube, this atomizing air being that portion of the air entering the burner at 9 which enters by ports 10 into an intermediate tube 3 having a converging-diverging discharge-end orifice; the remainder of the air entering at 9 is discharged through a nozzle 5 to converge on the issuing atomized fuel. The air and atomized fuel enter a ceramic tube 18 spaced from the wall 20, 21 of the combustion chamber to provide a recirculation passage 19, formed by the annular space outside the ceramic tube 18 or by flutings on its exterior; the ceramic tube also acts as a flame holder by the sudden enlargement of the combustion passage occurring at its forward end. Thus a part of the combustion product is recirculated to the point of entry of the air and atomized fuel to heat up the same. The ceramic tube is adjustable axially along the combustion chamber. Dilution air entering under the control of a damper 22 into an annular space around the ceramic wall 20, 21 of the combustion chamber may be whirlingly discharged through vanes 23 at the forward end of the combustion chamber to mix with the discharging products of the burner. The proportionate adjustment of the fuel and air is effected by simultaneous linked axial adjustment of the V-notched plunger 7 and of the intermediate tube 3 which co-operates with the nozzle 5 and the shaped exterior of the liquid-fuel tube 1 to regulate the atomizing air and the converging combustion air supply from the nozzle 5; the dilution-air damper 22 is also linked for simultaneous operation. Specification 679,142 is referred to.