Patent GB-804004-A (GB)
Title: Improvements in or relating to combustion apparatus
IPC: F23C15/00
Filed: 1955-08-26
Abstract: 804,004. Generating combustion products under pressure. JUNKERS & CO. G.m.b.H. Aug. 26, 1955 [Aug. 28, 1954], No. 24529/55. Class 51 (1). [Also in Group XIII] An oscillating column combustion apparatus for example for supplying combustion gases to a gas turbine engine or for use in a water heater, comprises two combustion chambers 22, 23 which operate out of phase with each other and are permanently interconnected by at least one resonance tube, pressure waves produced by combustion in either chamber causing gases which are contained in the resonance pipe to pass into the other chamber, means being provided to induce additional gas into the resonance pipe for delivery as a combustible mixture to the other chamber. The water-heating apparatus shown comprises two combustion chambers 22, 23 having resonance outlet pipes 39, 40, the two pipes being connected to a common exhaust pipe 41. Water jackets 52, 53, 54 are disposed around the combustion chambers, water being supplied thereto through a pipe 48, and the hot water discharging through an outlet pipe 55. A control device 44 contains a diaphragm 43 which forms two compartments 45, 46, the compartment 45 being connected by duct 47 to the water supply pipe and the compartment 46 being connected by duct 51 to the throat of a venturi 49 disposed in the water pipe, so that when water is flowing through the pipe, the diaphragm 43 is moved to the left as seen in the Figure. The diaphragm carries a rod 42 and valve 6 so that upon the movement of the diaphragm the valve 6 opens against the spring 7 and combustible gas flows through the pipe I to the compartment 8. Gas can then flow through the ducts 9, 9<SP>1</SP> and through the ducts 36 into the combustion chambers 22, 23. An igniting flame is provided at 5, being supplied with gas through the pipe 3, igniter tubes 35 being provided into the combustion chambers. The gas in one chamber, say 22, is caused to explode and part of the combustion gases passes outwardly through the resonance pipes 21, 27 which interconnect the two combustion chambers. The gases flowing to the chamber 23 cause the gas therein to explode and the two chambers continue to operate out of phase with each other. The resonance pipe 21 is formed in two parts each having a nozzle 24, 25 which connect with a combustible gas supply conduit 19, which connects to a chamber 15 which in turn is connected through an opening controlled by a valve 12 to the chamber 8. The valve 12 is connected to a diaphragm 14, one side of which is subjected to atmospheric pressure through the opening 17, while the other side is subject to pressure in the chamber 15. The other resonance pipe 27 which also connects the chambers 22, 23 is also formed in two parts each with a nozzle 28, 29, the two nozzles being connected to an intake 30 for atmospheric air. Combustion gases flowing outwardly from say the chamber 22 through the resonance pipes 21, 27 cause combustible gas and air respectively to be drawn in through the intakes 19, 30, the mixture of combustion gases, combustible gas and air passing into the chamber 23. The suction in the conduit 19 caused by the gas flowing through the venturi formed by the nozzles 24, 25 is communicated to the chamber 15 which causes the diaphragm to move to the right thereby opening valve 12 and allowing combustible gas to pass from the chamber 8 to the resonance pipe 21. The resonance pipes 21, 27 are formed at the inlets to the combustion chambers with convergent portions 32, 33 and the two pipes have common connections with the chambers. Small apertures 34 open to the atmosphere are provided at the connections of the resonance pipes with the combustion chambers.