Two-stage burner with two-layer counterflow vortex
The two-stage burner with a two-layer counter-vortex flow design addresses inefficiencies in air supply and combustion stability, enhancing fuel afterburning and reducing emissions, suitable for gas turbine plants.
Patent Information
- Application Number
- JP2025521215
- Authority / Receiving Office
- JP · JP
- Patent Type
- Applications
- Current Assignee / Owner
- Priority Date
- 2022-10-11
- Filing Date
- 2023-10-11
- Publication Date
- 2025-10-22
AI Technical Summary
Existing fuel combustion devices suffer from inefficient fuel combustion due to non-uniform air supply distribution, leading to significant circumferential variations and increased CO2 emissions, especially at part-load or near-stall modes, and are limited by tubular combustion chamber designs in gas turbine plants.
A two-stage burner with a two-layer counter-vortex flow design, featuring a burner body and flame tube with separate combustion zones and uniform air supply, utilizing swirlers and contoured ends to stabilize combustion and enhance afterburning efficiency.
Improves combustion zone formation and achieves efficient afterburning across a wide range of operating modes with reduced emissions, enabling stable operation and connection to gas turbine plants without additional adapters.
Smart Images
Figure 2025535131000001_ABST
Abstract
Description
[Technical Field]
[0001] CROSS-REFERENCE TO RELATED APPLICATIONS This application claims the benefit of priority from Russian Patent Application No. 2022126445, filed October 11, 2022, the entire contents of which are incorporated herein by reference in their entirety.
[0002] FIELD OF THE INVENTION Embodiments of the present invention relate to fuel-burning devices, and more particularly to vortex burners. [Background technology]
[0003] FIELD OF THE INVENTION The present invention relates to fuel-burning devices, and more particularly to vortex burners.
[0004] The prior art is a fuel combustion device described in Russian Patent No. 2708011, issued on December 3, 2019. The device includes three types of fuel supply devices. The first type of fuel supply device is in the form of a jet nozzle located within the swirler, with its flow channel outlet opening perpendicular to the end wall of the swirler and exiting at the smallest cross-section of the tangential nozzle swirler flow channel. The second type of device includes at least one centrifugal nozzle. The third type of device is in the form of a branch pipe installed in an axial hole in the end wall of the flame tube. The second and third types of fuel supply devices are located at the end of the flame tube opposite the swirler. The present invention provides improved firing reliability and stable operation for liquid, gaseous, and ballast fuels, including both non-combustible components and fuels containing water, pulverized solid combustible components, and their mixtures with water.
[0005] The particular device for burning fuel was closest in technical essence to the claimed invention and was used as a prototype.
[0006] Its disadvantages include inefficient fuel combustion due to significant circumferential variations in the air supply distribution between the tangential nozzle swirler and the front wall, which prevents efficient fuel afterburning over a wide range of operating modes; i.e., at part-load or near-stall modes in such designs, an unacceptable increase in CO2 emissions may occur. Furthermore, the use of tubular combustion chamber designs in prototypes may be limited, especially in gas turbine plants, where air must be uniformly supplied along the flame tube and an additional transition pipe with a special configuration is required to connect the installation's nozzle system. Summary of the Invention
[0007] A two-stage burner with two-layer counter-vortex flow includes a burner body and a flame tube containing an ignition device and an outlet nozzle, both coaxially arranged within the burner body. Between the burner body and the flame tube is an air channel with a first swirler disposed within it. The flame tube is made of first and second sections separated by a partition wall, each containing an outlet nozzle. The front wall of the first section has a toroidal shape and forms an inlet nozzle inside the first section, connected to the air channel. A first fuel supply is disposed within the inlet nozzle. Inside the first and second sections near the partition wall are second and third swirlers, connected to the air channel and second and third fuel supply devices, respectively. The first swirler is combined with the inlet nozzle. The outlet portion of the second section of the flame tube has a trapezoidal shape.
[0008] Effect: Improved formation of the combustion zone and efficient afterburning of fuel in a wide range of operating modes due to the use of contoured ends in the flame tube and the presence of two combustion zones, as well as uniform air supply to the channel between the body and the flame tube.
[0009] The subject matter which is regarded as the invention is particularly pointed out and distinctly claimed in the concluding portion of this specification. However, the invention, both as to organization and method of operation, together with its objects, features, and advantages, may best be understood by reference to the following detailed description when read in connection with the accompanying drawings. [Brief explanation of the drawings]
[0010] [Figure 1] 1 is a schematic diagram of a two-stage burner according to an embodiment of the present invention. DETAILED DESCRIPTION OF THE INVENTION
[0011] It will be appreciated that for simplicity and clarity of illustration, elements shown in the figures have not necessarily been drawn to scale. For example, the dimensions of some elements may be exaggerated relative to other elements for clarity. Further, where considered appropriate, reference numerals may be repeated among the figures to indicate corresponding or analogous elements.
[0012] In the following detailed description, numerous specific details are set forth in order to provide a thorough understanding of the present invention. However, it will be understood by those skilled in the art that the present invention may be practiced without these specific details. In other instances, well-known methods, procedures, and components have not been described in detail so as not to obscure the present invention.
[0013] For example, discussions utilizing terms such as “processing,” “computing,” “calculating,” “determining,” “establishing,” “analyzing,” and “checking” may refer to operation(s) and / or process(es) of a computer, computing platform, computing system, or other electronic computing device that manipulates and / or transforms data represented as physical (e.g., electronic) quantities in a computer's registers and / or memory into other data similarly represented as physical quantities in a computer's registers and / or memory, or other information non-transitory storage medium capable of storing instructions for performing operations and / or processes, although embodiments of the invention are not limited in this respect. As used herein, the terms “plurality” and “a plurality” may include, for example, “many” or “two or more.” The terms “plurality” or “a plurality” may be used throughout this specification to describe two or more components, devices, elements, units, parameters, etc. As used herein, the term “set” may include one or more items. Unless explicitly stated, method embodiments described herein are not constrained to a particular order or sequence. Furthermore, some of the described method embodiments or elements thereof may occur or be performed simultaneously, contemporaneously, or in parallel.
[0014] The technical result of the claimed invention is improved combustion zone formation and efficient afterburning of fuel over a wide range of operating modes due to the use of a contoured end in the flame tube, the presence of two combustion zones, and the uniform air supply to the channel between the housing and the flame tube, in which case the second section of the flame tube can be used as a transition tube for connecting to a gas turbine plant.
[0015] This result is achieved by the fact that a two-stage burner with a two-layer vortex counterflow is proposed, which comprises a burner body, a flame tube containing an ignition device installed coaxially therein, and an outlet nozzle, between which there is an air channel in which a first swirler is arranged, the flame tube is made in the form of two interconnected sections between which the outlet nozzle is located, the front wall of the first section has a toroidal shape and forms an inlet nozzle in the section connected to the air channel, a first fuel supply device is located in the inlet nozzle, and in each section of the outlet nozzle there are second and third swirlers connected to the air channel and second and third fuel supply devices, respectively.
[0016] The toroidal shape of the burner front wall reduces the resistance to airflow through the air channel to the inlet nozzle, contributing to the creation of a swirling near-axial flow and a combustion stabilization zone within the flame tube. In one embodiment of the present invention, the position of the first swirler can be combined with the inlet nozzle.
[0017] The two-section flame tube embodiment allows efficient afterburning of combustion products from the first section in the second section over the entire range of operating modes, due to the creation of separate vortices of the fuel-air mixture and combustion products in each section: counterflow (in the first section) and direct flow (in the second section). This embodiment of the pipe also allows a significant expansion of the range of stable operation of the combustion chamber with low exhaust emissions.
[0018] To enable the proposed burner to be used in gas turbine plants, the end of the second section of the flame tube on the combustion product outlet side has a trapezoidal shape so that it can be connected to the turbine nozzle device of the gas turbine plant.
[0019] Reference is now made to FIG. 1, which is a schematic diagram of a two-stage burner 100 according to an embodiment of the present invention.
[0020] The two-stage burner 100 with two-layer vortex counterflow comprises a housing 105 and a flame tube 110 containing an ignition device and consisting of two sections (see figure). An air channel 112 is formed between the body or housing 105 and the flame tube 110, through which the air mixture enters the flame tube 110. A first swirler 1 is arranged in this channel 112 and ensures the creation of a paraxial vortex within the flame tube that runs along the entire length of the flame tube.
[0021] The first section 111a and the second section 111b of the flame tube are interconnected and separated by a partition wall 115 having an opening in which the outlet nozzle 120 of the flame tube 110 is located. The outlet nozzle 120 is a cylindrical ring of diameter D2 with a longitudinal length that exceeds the thickness of the baffle. The flame tube 110 and the outlet nozzle 120 are arranged coaxially with respect to each other. Preferably, the body of the flame tube has a cylindrical shape.
[0022] The front wall 125 of the first section 111a has a toroidal shape (or a W-shaped profile). At the same time, its shape is formed so that the inward-protruding portion of the first section is an inlet window 130 connected to an air channel, which essentially repeats the shape of the front wall of the first section and enters the inlet window. This particular window 130 is an inlet nozzle with a diameter D1 through which the airflow for the paraxial vortex enters. Preferably, the first swirler 1 is located near the inlet nozzle or directly within the inlet nozzle itself. A first fuel supply 150a is also located within the inlet nozzle 130.
[0023] The toroidal shape of the front wall 125, and therefore the air channels in this region, smoothly reverse the airflow in the opposite direction, contributing to the creation of axial flow within the flame tube 105. The presence of swirlers within the channels causes such flow to swirl and become more efficient at mixing with fuel from the first fuel supply 150a.
[0024] The second swirler 2 and the third swirler 3, connected to the air channel 112, are installed on the inner surfaces of the first section 111a and the second section 111b, respectively. These swirlers are located near the partition wall 115 and generate peripheral vortices of the fuel-air mixture within those sections. In this case, the second swirler 2 ensures that the vortex motion in the first section 111a moves in the opposite direction to the axial vortex motion (a counterflow is generated). The third swirler 3 generates a paraxial vortex in the second section 111b, which moves in one direction with the paraxial flow (a parallel flow is generated).
[0025] The second swirler 2 and the third swirler 3 are connected to second and third fuel supply devices 150b and 150c, respectively.
[0026] The partition 115 between the sections allows for separation of the combustion zones, forming combustion zone 1 and combustion zone 2, thereby facilitating afterburning of residual gases from the first section to the second section.
[0027] The three fuel supplies 150a, 150b, 150c increase the range of stable operation of the claimed burner 100 when its load changes. Therefore, during operation of the two-stage burner 100 at low power levels (less than 30% of the maximum), fuel is not supplied to the third fuel supply and afterburning of the residual gases of the first section is carried out due to the airflow from the third swirler.
[0028] Methane, propane, butane, diesel, kerosene or gasoline can be used as fuel. In some burner applications, it is also possible to provide a third fuel source, a low-calorie fuel such as synthesis gas or pyrolysis gas.
[0029] The carried out field tests show that the proposed burner design works most efficiently with values of the diameter of the inlet nozzle D1 corresponding to 0.2-0.4D and the diameter of the outlet nozzle D2 corresponding to 0.6-0.8D, where D is the diameter of the flame tube.
[0030] To use the proposed two-stage burner 100 as part of a gas turbine plant, the second section 111B of the flame tube 105 has a contoured shape that allows it to be connected to the nozzle device of the turbine of the gas turbine plant without using an additional adapter in the form of a nozzle. In this embodiment, the second section 111b is a gas collector. Structurally, the front part of the second section, which is attached to the first section, has a cylindrical design, while the outlet part, which is connected to the gas turbine plant, has a trapezoidal shape.
[0031] The two-stage burner with two-layer counterflow vortex operates as follows: Air is supplied to the air channel and passes through the first, second, and third swirlers into the corresponding sections of the flame tube. The first and second fuel supply devices are supplied with fuel, which mixes with the air to form a fuel-air mixture. The fuel-air mixture from the second swirler moves spirally along the inner surface of the first section, creating a peripheral vortex that cools the flame tube wall. Upon reaching the toroidal wall, this vortex unfolds and merges with the central vortex formed by the first swirler from the inlet nozzle, forming a stable combustion stabilization zone, which is ignited in start-up mode by the ignition device installed in the first section. Combustion products pass from the first section through the outlet nozzle into the second section, where they mix with the airflow from the third swirler, burning off any remaining combustible gases. The presence of the three swirlers (1, 2, and 3) through which the air enters reduces the combustion temperature, allowing for the control of harmful emissions of nitrogen oxides and carbon oxides. When the rated output of the burner is reached, fuel can be supplied through a third fuel supply device, which mixes with the air flow of the third swirler to form a fuel-air mixture, which is then ignited in the axial zone of the second section.
[0032] Unless explicitly stated, the method embodiments described herein are not constrained to a particular order in time or chronological order. Furthermore, some of the described method elements may be skipped or repeated during the sequence of operations of the method.
[0033] While certain features of the invention have been illustrated and described herein, many modifications, substitutions, changes, and equivalents will occur to those skilled in the art. It is therefore to be understood that the appended claims are intended to cover all such modifications and changes that fall within the true spirit of the invention.
[0034] Various embodiments are presented, each of which can of course include features from the other embodiments presented, and embodiments not specifically described can include various features described herein.
Claims
1. 1. A two-stage burner with two-layer counter-vortex flow, comprising a burner body and a flame tube including an ignition device and an outlet nozzle coaxially disposed therein, wherein between the burner body and the flame tube there is an air channel in which the first swirler is disposed, the flame tube being made of the first section and the second section separated by a partition wall including an outlet nozzle, the front wall of the first section having a toroidal shape and forming an inlet nozzle inside the first section connected to the air channel, the first fuel supply device being disposed within the inlet nozzle, and second and third swirlers connected to the air channel and the second and third fuel supply devices, respectively, inside the first and second sections of the partition wall.
2. The two-stage burner of claim 1 , wherein the first swirler is combined with the inlet nozzle.
3. 10. The two-stage burner of claim 1, wherein the outlet of the second section of the flame tube has a trapezoidal shape.
4. 2. The two-stage burner according to claim 1, wherein the diameter of the inlet nozzle corresponds to 0.2-0.4D, and the diameter of the outlet nozzle is 0.6-0.8D, where D is the diameter of the flame tube.