|Publication number||US2829494 A|
|Publication date||Apr 8, 1958|
|Filing date||Oct 23, 1956|
|Priority date||Oct 23, 1956|
|Publication number||US 2829494 A, US 2829494A, US-A-2829494, US2829494 A, US2829494A|
|Inventors||Christensen Willard L|
|Original Assignee||Christensen Willard L|
|Export Citation||BiBTeX, EndNote, RefMan|
|Patent Citations (5), Referenced by (6), Classifications (10)|
|External Links: USPTO, USPTO Assignment, Espacenet|
April4 8, 1958 w. L. cHRls'rENsEN PRIMARY ZONE FOR GAS TURBINE COMBUSTOR Filed Oct. 25. 1956 M/ Nm..
the primary zone.
United States Patent O "ce PRIMARY ZQNE FR GAS TURBINE CMBUSTOR Willard L. Christensen, Newtown, Conn., assigner, by mesne assignments, to the United States of America as represented by the Secretary of the Navy Application cto'ber 23, 1956, Serial No. 617,895
2 Claims. (Cl. 6039.71)
This invention relates to a primary burning zone for a gas turbine combustor.
ln gas turbine engines, jet combustion is accomplished by the `continuous burning of fuel in a confined space to obtain power directly from the hot products of cornbustion. in such engines a high velocity air stream is forced by a compressor into the combustion chamber where fuel is m'med with the compressor air. Combustion occurs primarily in the flame zone and this provides the Working medium for the turbine.
The optimum performance of a compressonburnerturbine type engine is to obtain the highest stable heat release in the combustion chamber. This high efficiency should be for a wide range of fuel' rates and air flow conditions. Since there are few variables in a given engine design, a basic method of obtaining increased efciency is to pre-treat the fuel to stabilize the flame. The performance is greatly increased if a catalytic agent can be employed in the primary zone to provide a Stabi* lized region of burning.
The present invention pre-treats the fuel by a heated target which utilizes the heat from the burning gases in The incoming fuel is directed at high velocity onto the target where it is heated to vaporization and combines with hot gases. This mixture is then united with the primary air from the compressor and introduced into the combustion chamber. To assist in complete burning in the unit the target may be coated with a catalytic agent.. Thus, burning efficiency is increased and stabilized enabling a great reduction in length and weight.
lt is an object of this invention to provide a gas turbine combustor wherein the income fuel is pre-treated by a heated target.
lt is a further object of this invention to provide a gas turbine combustor wherein the injected fuel is vaporized by heat derived from the primary burning section.
Other objects and many of the attendant advantages of this invention will be readily appreciated as the same becomes better understood by reference to the following detailed description when considered in connection with the accompanying drawing, the single figure of which shows a cutaway longitudinal section through a gas turbine combustor embodying the invention. p
Referring more particularly to the drawing, the preferred embodiment of the invention includes a gas turbine combustor having an outer casing 1. Mounted within and spaced from the outer casing l is an open ended cylindrical casing 2 having a plurality of openings 3 through which the necessary secondary or cooling air may enter. Casing 2 is rigidly connected to casing 1 by a plurality of struts extending between the casings, two of the struts 38 and 40 being shown and being secured to the casings by any suitable means such as welding.
A circular bale 4 is` located in the forward end of the cylindrical casing 2. A fitting 5 on the `baille 4 receives the fuel line 6 so that fuel may be ejected through the baflle. Spaced from the rearward side of the baille 4 2,829,494 Patented Apr. 8, 1958 there is a circular ceramic target 7 having a downstream face 8 and an upstream face 10. The target 7 is po sitioned parallel to but spaced from the baie 4 so that fuel ejected from the fitting 5 will impinge on the target. The downstream face 3 of the target is exposed to the primary combustion zone 9. The hot gases in the com* bustion zone 9 heat the ceramic target`7 so that the fuel directed on the target 7 by the fitting 5 is vaporized. Both the downstream face 8 and the upstream face 10 of the target 7 are coatedwith a catalytic agent. As a general rule, catalytic agents are not effective on a surface that is wetted by fuel. Howeven since the upstream `face 1lb of the target 7 in the preferred embodiment of the invention is at a sufliciently high temperature, the upstream face 10 will be in a gaseous area and a catalytic agent would thus be effective.
A fuel mixing chamber l1 is located between the baie 4 and the target 7. This chamber is partially enclosed by a tapering circular shield 12. The front end 13 of the shield 12 is parallel to but spaced from the curved lip portion 14 of the baille 4 providing an annular opening 15 through which the fuel mixture may pass. The other end 16 of the shield 12 is concentric to but spaced from the target 7 to 'form a ring shaped opening 17 through which some of the hot gases from the primary combustion zone 9 may pass. The baffle 4, the target 7 and the shield i2 are secured together to form one unit and the unit is mounted in the forward end of the casing 2. Batlle 4 and shield 12 are rigidly connected by a plurality of strut members 24, 26 and 28 and target 7 is connected to the end 16 of shield 12 by a plurality of pins 30 (only two shown). The unit assembly of baiile 4, target 7 and shield 12 is in turn rigidly attached to cylindrical casing 2 by strut members 32, 34 and 36 which extend between casing 2 and shield 12 and which may be secured thereto by any suitable means such as welding.
The primary air is introduced through an annular venturi 18 surrounding the fuel chamber. The venturi 13 is formed by a ring shaped member 19 having a curved side wall 20 concentric with and spaced from the curved lip portion 14. The side wall 20 extends rearwardly past the end 13 of the section 12. The member 19 is mounted on the casing 2 to provide an annular opening 21. Member 19 is connected to casing 2 in this preferred embodiment by a plurality of rods 42 (only two shown) which extend between the member 19 and` casing 2 and which are secured thereto by any suitable means such as by welding (not shown). It will be appreciated, however, that any suitable type of connecting means other than rods 42 may be used.
In operation of the target 7 is heated to a high temperature by the het gases in the primary combustion chamber. Fuel is injected into the fuel mixing chamber 11 and is vaporized by the heated target. The vaporized fuel then mixes with the hot gases entering the fuel mixing chamber through the circular opening 17. As the primary air passes through the annular venturi 1S surrounding the `fuel mixing chamber, it draws the fuel-hot gas mixture out of the chamber and into the high velocity primary air stream. The turbulence caused by the expansion at locations 22 thoroughly mixes the combustionable elements so that they may be ignited and burned in the primarycharnber.
This type of gas turbine combustor primary zone is applicable to either a can or an annular type burner where a series of these chambers would be arranged on the upstream face.
Obviously many modifications and variations of the present invention are possible in the light of the above teachings. It is therefore to be understood that within the scope of the appended claims the invention may be practiced otherwise than as specifically described.
What is claimed is:
1. A primary zone for a gas turbine combustor comprising an outer casing, an inner cylinder mounted in said casing and open at both ends, a fuel supply means mounted in said casing in the center thereof and adjacent one end of said cylinder, an annular venturi surrounding said fuel supply means through which primary air oWs, an annular shield mounted in said cylinder spaced from said venturi and forming a fuel and air mixing chamber, a ceramic target mounted in said mixing chamber and being of a lesser diameter than the inner diameter of the chamber whereby hot gases from the rest of the cylinder which forms a primary combustion zone will pass between said target and said shield and vaporize the incoming fuel and the primary air passing through the venturi will draw the mixture thus formed into the primary combustion zone.
2. A primary zone for a gas turbine combustor as in claim 1 wherein the ceramic target is coated with a catalytic agent.
References Cited in the file of this patent UNITED STATES PATENTS 1,052,588 Janicki Feb. 11, 1913 2,385,833 Nahigyan Oct. 2, 1945 2,433,943 Zwicky et al Ian. 6, 1948 2,554,401 Christensen et a1 May 22, 1951 FOREIGN PATENTS 201,112 Australia Feb. 6, 1956
|Cited Patent||Filing date||Publication date||Applicant||Title|
|US1052588 *||Apr 12, 1911||Feb 11, 1913||John Janicki||Hydrocarbon power-generator.|
|US2385833 *||Jan 27, 1943||Oct 2, 1945||Nahigyan Kevork K||Fuel vaporizer for jet propulsion units|
|US2433943 *||Mar 11, 1944||Jan 6, 1948||Aerojet Engineering Corp||Operation of jet propulsion motors with nitroparaffin|
|US2554401 *||Jul 18, 1946||May 22, 1951||Christensen Willard L||Combustion apparatus provided with gas backflow-inducing means adjacent the nozzles|
|AU201112B *||Title not available|
|Citing Patent||Filing date||Publication date||Applicant||Title|
|US3656297 *||Aug 28, 1970||Apr 18, 1972||Rolls Royce||Combustion chamber air inlet|
|US4825658 *||Dec 11, 1987||May 2, 1989||General Electric Company||Fuel nozzle with catalytic glow plug|
|US5355668 *||Jan 29, 1993||Oct 18, 1994||General Electric Company||Catalyst-bearing component of gas turbine engine|
|US5685156 *||May 20, 1996||Nov 11, 1997||Capstone Turbine Corporation||Catalytic combustion system|
|US6453658||Feb 24, 2000||Sep 24, 2002||Capstone Turbine Corporation||Multi-stage multi-plane combustion system for a gas turbine engine|
|US6684642||Jun 17, 2002||Feb 3, 2004||Capstone Turbine Corporation||Gas turbine engine having a multi-stage multi-plane combustion system|
|U.S. Classification||60/723, 60/750, 60/736|
|International Classification||F23R3/04, F23R3/10, F23R3/30|
|Cooperative Classification||F23R3/10, F23R3/30|
|European Classification||F23R3/10, F23R3/30|