GB1351212A - Method for combusting fuels which are ejected from an orifice in a manner to form a substantially conically shaped curtain of fuel and a device for putting the method into effect - Google Patents

Abstract

1351212 Spray burners R COLLIN CONSULTING AB 19 April 1971 [24 March 1970] 24963/71 Heading F4T A device for producing improved combustion of fuel comprises a fuel nozzle 25, having an orifice 35 therein and located within a body 24 which widens towards the fuel ejection end of the device, and two co-axial tubes 28 and 29 terminating in flanges 30 and 31; and in use fuel is sprayed through the orifice 35 to form a conical curtain and combustion air, given a rotatory motion by guide vanes 27 and an ejector action by a restriction 34, is delivered through the annular channel between the body 24 and tube 28 to form an envelope co-axial with and rotating about the fuel curtain while also creating a region of reduced pressure in front of the body 24. In addition air is directed between the flanges 30 and 31 to set up by ejector action eddies 38 which in turn create stronger eddies 39 to recirculate hot smoke gases to the base of the combustion zone, which recirculation together with the reduced pressure region caused by the combustion air concentrates the combustion zone rearwardly and inwardly towards the fuel orifice 35 while the fuel and air cones are displaced to coincide in a bowl shape as shown. Vanes may be provided in the channel between tubes 28 and 29 or else the opening between flanges 30 and 31 may be in the form of a ring of suitably oriented openings in order to give the air issuing therefrom a tangential component of velocity. In a further embodiment of the invention an annular member is spaced in front of the coaxial tubes, which have no bent round flanges, so as to produce different eddy formations. In a third embodiment the outer co-axial tube extends further than the inner tube and is provided with an annular ejector opening located beyond the ends of the nozzle and inner tube. A fourth embodiment has a plurality of co-axial tubes with annular air openings between the ends of each pair of tubes which openings are in the form of guide passages inclined at different angles to the radial plane of the device. The invention is also described as being embodied by a fuel nozzle and co-axial outlet for combustion air, the fuel curtain and air envelope issuing from which being drawn outwardly into a bowl shape by the suction of the surrounding atmosphere through an annular opening or ring of orifices actuated by a suction fan.