Patent GB-622537-A (GB)
Title: Improvements in or relating to furnaces
IPC: F02C7/141
Filed: 1947-03-21
Abstract: 622,537. Generating combustion products under pressure. BABCOCK & WILCOX, Ltd., and ZOLLER, R. E. March 21, 1947, No. 7846. [Class 51 (i)] A furnace for a gas turbine plant comprises a combustion chamber enclosed within and spaced from a pressure-resisting metal casing, the combustion chamber being formed by a wall faced internally with refractory material in which are embedded metal elements projecting inwardly towards the combustion space from tubes carrying a cooling fluid and the space between the pressure-resisting casing and the wall is occupied at least in part by a passage through which a gaseous cooling fluid flows. The furnace for supplying working fluid to a gas turbine, Fig. 1, has a pressure-resisting cylindrical casing 30 which encloses a steam cooled cylindrical wall structure 31, having an opening at one end in which is arranged an atomising oil burner 13 fitted with an impeller plate 34 designed to cause the air entering the combustion space to swirl. Adjustable louvres 35 control the air supply. The wall 32 of the wall structure 31 is formed of chrome ore refractory material 200, Fig. 4 applied in a plastic condition over the inwardly facing surfaces of twenty-four tube coils 39 which surfaces are provided with metal studs 201. Part of one of the coils 39 defines the end wall 40 of the combustion space. A further tube coil 41 is arranged to form a convergent divergent passage 42, 44 forming the exit from the combustion space 36. The various tube coils are cooled by 'steam from an inlet 45 and terminate in nozzles 47 arranged in the wall of the combustion space so as to deliver the steam into the combustion space with a whirling motion in the same direction as the whirling motion of the combustion air produced by the plate 34 and as a stream flowing initially at least in part in contact with the adjacent wall. The tube coil 41 terminates in a nozzle 47<SP>1</SP> and delivers steam into the combustion gases after they leave the combustion space. The pressure casing 30 is formed with an inlet for the compressed air. One part of the compressed air passes through apertures 49 and mixes with the combustion gases and the other part flows through the annular space 50. Part of the air flowing through the space 50 enters the combustion space through the firing opening 33 and the remainder through the ports 51 which are inclined. so as to give the entering air a whirling motion in the same direction as the whirling motion of air produced by the impeller plate 34. In a modified form of furnace for reheating gases in a gas turbine plant, an additional set of steam cooled tube coils is arranged between the coils 39 and the casing wall 30. The gases from the high pressure turbine pass through the inlet 48 and a supply of compressed air is fed through an additional inlet in the casing wall 30 to flow through the passage formed between the additional set of coils and the casing to the firing opening 33. According to the Provisional Specification compressed air may be used to cool the coils which air may be taken from the compressor of a gas turbine plant and may be boosted by an additional compressor. When a reheating chamber is used one of the banks of coils may be used for generating steam for other purposes. Specification 579,591 is referred to in the Provisional Specification.