Full-premixing type annular combustion chamber based on metal fiber cloth
By using a fully premixed annular combustor based on metal fiber cloth, the waste heat of turbine exhaust gas is used to gasify and preheat fuel, solving the problems of high combustion temperature, high NOx emissions and complex cooling in traditional combustors, and achieving low-temperature stable combustion and efficient energy utilization.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2026-02-05
- Publication Date
- 2026-04-14
AI Technical Summary
Traditional combustion chambers have excessively high combustion temperatures, resulting in high NOx emissions. The turbine and flame tube have complex cooling requirements. Fuel atomization relies on high pressure and precision nozzles. Combustion is unstable at low stoichiometry, making it difficult to balance combustion efficiency, pollutant emissions, and cooling requirements.
The fully premixed annular combustion chamber based on metal fiber cloth is adopted. It utilizes the waste heat of turbine exhaust gas to complete fuel gasification and preheats the fuel gas through iron-chromium-aluminum metal fiber cloth to achieve stable combustion of premixed gas, reduce flame temperature, simplify cooling design, and improve combustion efficiency and reliability by combining with a distributed regeneration system.
It achieves stable combustion at low equivalence ratios, reduces NOx emissions, simplifies cooling structures, improves combustion efficiency and cleanliness, enhances energy utilization efficiency, and reduces fuel consumption.
Smart Images
Figure CN121854901A_ABST
Abstract
Description
Technical Field
[0001] This invention relates to the field of aerospace equipment technology, and in particular to a fully premixed annular combustion chamber based on metal fiber cloth. Background Technology
[0002] The combustor of an aero-engine or gas turbine is a core component of the power plant, and its combustion organization directly determines the thermal efficiency, pollutant emissions, and operational reliability of the power plant. Traditional aero-engine or gas turbine combustors generally adopt diffusion combustion or partially premixed combustion modes. In these combustion modes, fuel is atomized through nozzles and mixed with air for combustion, and the flame temperature in the combustion zone typically exceeds 1800K.
[0003] Excessively high combustion temperatures place stringent demands on turbine blade materials and cooling systems, while also significantly increasing the formation of thermal nitrogen oxides (NOx). To reduce turbine inlet temperature, a large amount of cooling air needs to be mixed into the high-temperature combustion gas, which not only increases the complexity of the combustion organization but also reduces cycle thermal efficiency. Furthermore, traditional combustors require complex flame tube cooling structures (such as film cooling and impingement cooling) to prevent overheating and damage to the flame tube. In conventional combustors, fuel atomization requires high fuel pressure and complex nozzle design, and fuel often struggles to burn stably at low stoichiometric ratios, limiting the path to reducing flame temperature through lean combustion. Therefore, existing technologies present a contradiction between combustion efficiency, pollutant emissions, and cooling requirements. Summary of the Invention
[0004] To address the shortcomings of existing technologies, this invention provides a fully premixed annular combustor based on metal fiber cloth. This solves the technical problems of traditional combustors, such as excessively high combustion temperatures leading to high NOx emissions, complex turbine and flame tube cooling requirements, reliance on high pressure and precision nozzles for fuel atomization, unstable combustion at low stoichiometry, and difficulty in balancing combustion efficiency, pollutant emissions, and cooling requirements. It achieves stable combustion at low stoichiometry by leveraging the heat storage and preheating functions of the metal fiber cloth and the exhaust gas vaporization of fuel, thereby reducing flame temperature and NOx emissions, simplifying cooling and atomization design, and balancing combustion efficiency and operational reliability.
[0005] To solve the above-mentioned technical problems, the present invention provides the following technical solution: a fully premixed annular combustion chamber based on metal fiber cloth, comprising a combustion chamber shell, a baffle plate fixedly connected to the inner end of the combustion chamber shell, a partition plate extending into the interior of the combustion chamber shell fixedly connected to the inner edge of the baffle plate, a turbine exhaust channel for discharging high-temperature exhaust gas on the inner side of the partition plate, a combustion chamber formed between the outer side of the partition plate and the inner wall of the combustion chamber shell, an annular flame tube with a hollow interior for ignition and combustion fixedly connected inside the combustion chamber, a deflection channel for guiding the premixed gas flow installed at the inner end of the annular flame tube, metal fiber cloth for preheating premixed gas welded to the upper and lower inner walls of the annular flame tube respectively, the upper wall of the annular flame tube and the inner wall of the combustion chamber shell forming an outer flow channel of the combustion chamber, the lower wall of the annular flame tube and the outer wall of the partition plate forming an inner flow channel of the combustion chamber, and the tail end of the inner flow channel of the combustion chamber is a closed structure, and a fuel gasification system for supplying gasified fuel for combustion is provided on the baffle plate.
[0006] A further improvement is that all metal components in the combustion chamber shell are made of GH3625 nickel-chromium-molybdenum-niobium solid solution-strengthened high-temperature alloy.
[0007] A further improvement is that small permeation holes are provided on the inner walls of both the upper and lower sides of the annular flame tube, and a large flow deflector hole communicating with the inner flow channel of the combustion chamber is provided through the deflector flow channel, and the porosity of the deflector flow channel is greater than that of the annular flame tube.
[0008] A further improvement is that the metal fiber cloth is made of iron-chromium-aluminum metal fiber cloth, and the iron-chromium-aluminum metal fiber cloth is a three-dimensional porous material.
[0009] A further improvement is that the fuel vaporization system includes a liquid fuel manifold and a vaporized fuel manifold opened within the baffle plate, with the vaporized fuel manifold located inside the liquid fuel manifold. Multiple fuel heat exchange vaporization pipes are fixedly connected in a ring array on the liquid fuel manifold, and the ends of the fuel heat exchange vaporization pipes extend into the vaporized fuel manifold. The baffle plate is respectively fixed with a liquid fuel injection port extending into the liquid fuel manifold and a gaseous fuel outlet extending into the vaporized fuel manifold.
[0010] A further improvement is that the fuel heat exchange vaporization pipe is installed in a U-shape on the inner wall of the turbine exhaust channel, and its flow path is from the head to the tail of the turbine exhaust channel, and then back to the head to inject vaporized fuel into the manifold.
[0011] A further improvement is that the sealing plate is provided with a plurality of igniter mounting holes arranged in a circular array, and an igniter is installed in each of the igniter mounting holes.
[0012] A further improvement is that multiple support plates are fixedly connected to the inner wall of the turbine exhaust channel, and a pneumatic cone is fixedly connected to the end of the support plate.
[0013] By employing the above technical solution, the present invention provides a fully premixed annular combustion chamber based on metal fiber cloth, which has at least the following beneficial effects: 1. This invention relies on the waste heat of turbine exhaust gas to complete the full gasification of fuel, and combines it with the efficient preheating of the oil-gas premixed gas by iron-chromium-aluminum metal fiber cloth to achieve stable combustion of the premixed gas, significantly reduce the flame combustion temperature, and the high-temperature gas can match the turbine temperature resistance requirements without mixing with cooling air, reducing air loss, allowing more high-quality heat energy to directly drive the turbine to do work, improving combustion work efficiency, and achieving uniform and stable low-temperature combustion at a low stoichiometric ratio.
[0014] 2. The combustion temperature of this invention is controllable, below the threshold of 1500K where thermal NOx is generated in large quantities, fundamentally and significantly reducing the amount of thermal NOx generated, achieving ultra-low emissions of nitrogen oxides, which meets the environmental emission requirements of aviation and gas turbine fields. At the same time, the porous structure of the metal fiber cloth makes the micro-mixing of the premixed gas more uniform, reducing incomplete combustion products, improving combustion cleanliness, achieving clean and low-emission combustion, and inhibiting the generation of pollutants from the source.
[0015] 3. By constructing a low-temperature combustion environment, this invention eliminates the need for a cooling air mixing system at the turbine inlet, thus avoiding the problems of total pressure loss and uneven gas temperature field caused by mixing. The annular flame tube wall utilizes a self-balancing mechanism of "heat recovery-cooling" with metal fiber cloth, eliminating the need for additional complex cooling structures such as gas film and impact. The fuel is premixed with air after being vaporized by the waste heat of the exhaust gas, thus eliminating the dependence of traditional combustion chambers on high-pressure fuel systems and precision atomizing nozzles, simplifying the fuel supply system, resulting in a more compact overall structure and reduced processing and assembly difficulty.
[0016] 4. This invention recovers the waste heat of high-temperature exhaust gas in the turbine exhaust channel through a U-shaped fuel heat exchange and vaporization pipe, heats and vaporizes the liquid fuel and preheats it to 523K, achieving efficient recovery and energy reuse of waste heat from exhaust gas, improving fuel activity. At the same time, the distributed wall regeneration system constructed with metal fiber cloth recovers part of the heat released by combustion and uses it to preheat the incoming premixed gas, realizing energy circulation within the combustion system, promoting complete combustion of fuel, significantly improving the overall thermal utilization efficiency of fuel, and reducing fuel consumption. Attached Figure Description
[0017] The accompanying drawings, which are provided to further illustrate this application and form part of this application, illustrate exemplary embodiments of this application and are used to explain this application, but do not constitute an undue limitation of this application.
[0018] In the attached diagram: Figure 1 This is a schematic diagram of the overall structure of the present invention; Figure 2 This is a schematic diagram of the rear view structure of the present invention; Figure 3This is a side view of the structure of the present invention; Figure 4 This is a cross-sectional internal structure diagram of the fuel gasification system of the present invention; Figure 5 This is a schematic diagram of the overall cross-sectional internal structure of the present invention; Figure 6 This is a schematic diagram of the independent structure of the annular flame tube and the deflecting flow channel of the present invention.
[0019] In the diagram: 1. Combustion chamber outer shell; 2. Baffle plate; 3. Divider plate; 4. Turbine exhaust channel; 5. Combustion chamber; 6. Annular flame tube; 7. Turning channel; 8. Metal fiber cloth; 9. Outer channel of the combustion chamber; 10. Inner channel of the combustion chamber; 11. Fuel vaporization system; 111. Liquid fuel manifold; 112. Vaporized fuel manifold; 113. Fuel heat exchange vaporization pipe; 114. Liquid fuel injection port; 115. Gaseous fuel outlet; 12. Igniter mounting hole; 13. Support plate; 14. Pneumatic cone. Detailed Implementation
[0020] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.
[0021] Addressing the problems of excessively high NOx emissions due to high combustion temperatures in traditional combustors, complex turbine and flame tube cooling requirements, reliance on high pressure and precision nozzles for fuel atomization, unstable combustion at low stoichiometry, and difficulty in balancing combustion efficiency, pollutant emissions, and cooling requirements, this embodiment provides a fully premixed annular combustor based on metal fiber cloth. This combustor leverages the heat storage and preheating functions of the metal fiber cloth, as well as its ability to vaporize fuel from exhaust gas, to achieve stable combustion at low stoichiometry, reduce flame temperature and NOx emissions, simplify cooling and atomization design, and balance combustion efficiency and operational reliability. Please refer to... Figures 1-6The fully premixed annular combustor based on metal fiber cloth includes a combustor shell 1, a baffle plate 2 fixedly connected to the inner end of the combustor shell 1, a partition plate 3 fixedly connected to the inner edge of the baffle plate 2 extending into the interior of the combustor shell 1, a turbine exhaust channel 4 for emitting high-temperature exhaust gas on the inner side of the partition plate 3, a combustor 5 formed between the outer side of the partition plate 3 and the inner wall of the combustor shell 1, a hollow annular flame tube 6 for ignition and combustion fixedly connected inside the combustor 5, a deflection channel 7 for guiding the flow of premixed gas installed at the inner end of the annular flame tube 6, metal fiber cloth 8 for preheating premixed gas welded to the upper and lower inner walls of the annular flame tube 6, an outer channel 9 formed by the upper wall of the annular flame tube 6 and the inner wall of the combustor shell 1, and an inner channel 10 formed by the lower wall of the annular flame tube 6 and the outer wall of the partition plate 3, with the tail end of the inner channel 10 being a closed structure, and a fuel gasification system 11 for supplying gasified fuel for combustion is provided on the baffle plate 2.
[0022] All metal components in the combustion chamber outer shell 1 are made of GH3625 nickel-chromium-molybdenum-niobium solid solution strengthened high-temperature alloy. Small permeation holes are provided on the inner walls of both the upper and lower sides of the annular flame tube 6. A large baffle hole communicating with the inner flow channel 10 of the combustion chamber is provided through the deflecting flow channel 7, and the porosity of the deflecting flow channel 7 is greater than that of the annular flame tube 6. The metal fiber cloth 8 is made of iron-chromium-aluminum metal fiber cloth, which is a three-dimensional porous material. The pressurized air from the external compressor outlet is uniformly mixed with the vaporized fuel at the compressor outlet. The premixed air is blown out by the compressor and enters the outer flow channel 9 of the combustion chamber 5 from the tail end. During this process, a portion of the premixed air enters the annular flame tube 6 through the small permeation holes on the upper wall and burns inside the annular flame tube 6. The remaining premixed air passes through the large baffle hole on the deflecting flow channel 7 at the end of the outer flow channel 9 of the combustion chamber and turns 180° before entering the inner side of the combustion chamber. The premixed gas flows from the flow channel 10 towards its tail end. During this process, the remaining premixed gas enters the annular flame tube 6 through the permeation holes on the lower wall of the annular flame tube 6. When the premixed gas permeates into the annular flame tube 6 through the permeation holes on both the upper and lower walls, the premixed gas flows through the iron-chromium-aluminum metal fiber cloth 8, resulting in a certain pressure loss. However, the pressure loss of the premixed gas when flowing through the turning flow channel 7 is very small. This ensures that the pressure of the premixed gas in the inner side flow channel 10 of the combustion chamber is greater than the pressure of the high-temperature combustion gas in the annular flame tube 6, thereby ensuring the pressure of the premixed gas in the inner side flow channel 10 of the combustion chamber. The premixed gas can smoothly penetrate into the annular flame tube 6. Inside the annular flame tube 6, the premixed gas is ignited by the igniter and forms a stable low-temperature flame. The high-temperature gas that has completed combustion flows out from the gas outlet at the tail of the annular flame tube 6, driving the downstream turbine to do work. The high-temperature exhaust gas after doing work enters the turbine exhaust channel 4 located in the center. The metal fiber cloth 8 constitutes a "natural" distributed regenerator, constructing a distributed "wall regeneration-permeation combustion" system. On the one hand, with the unique dual-channel airflow organization, the permeation process itself achieves microscopic uniform mixing of fuel and oxidant. On the other hand, when the relatively low-temperature premixed gas flows through and is forced through the high-temperature metal fiber cloth 8, the huge heat capacity and surface area of the metal fiber cloth 8 can quickly transfer some of the heat released by combustion to the incoming premixed gas, effectively preheating it. The preheated premixed gas is ignited in the annular flame tube 6, and low stoichiometric combustion is carried out to produce low-temperature gas. The low-temperature gas is guided to directly drive the turbine to do work. At the same time, the metal fiber cloth 8 itself is cooled by the premixed gas. This process achieves a highly efficient regeneration cycle.
[0023] Specifically, the fuel vaporization system 11 includes a liquid fuel manifold 111 and a vaporized fuel manifold 112 opened in the baffle plate 2. The vaporized fuel manifold 112 is located inside the liquid fuel manifold 111. Multiple fuel heat exchange vaporization pipes 113 are fixedly connected in a ring array on the liquid fuel manifold 111. The ends of the fuel heat exchange vaporization pipes 113 extend into the vaporized fuel manifold 112. A liquid fuel injection port 114 extending into the liquid fuel manifold 111 and a gaseous fuel outlet 115 extending into the vaporized fuel manifold 112 are fixedly connected to the baffle plate 2.
[0024] The fuel heat exchange vaporization pipe 113 is U-shaped and installed on the inner wall of the turbine exhaust channel 4. Its flow path is from the head to the tail of the turbine exhaust channel 4, and then back to the head to inject vaporized fuel manifold 112. Liquid fuel is injected into the liquid fuel manifold 111 from the liquid fuel injection port 114. The fuel is evenly distributed into multiple fuel heat exchange vaporization pipes 113 in the liquid fuel manifold 111. The fuel flows in the fuel heat exchange vaporization pipes 113, from the head to the tail of the turbine exhaust channel 4, and then back to the head to inject vaporized fuel manifold 112. Thus, the high-temperature exhaust gas discharged from the turbine exhaust channel 4 vaporizes the liquid fuel in the fuel heat exchange vaporization pipes 113. The heated and vaporized fuel in the latter half of section 113 flows into the vaporized fuel manifold 112 and is then transported to the compressor outlet through the gaseous fuel outlet 115 and external pipe, where it is injected into the air to mix. It then enters the combustion chamber 5. The inner diameter of the fuel heat exchange vaporization pipe 113 is 0.8 mm, the total length of the return flow is 400 mm, the turbine exhaust is 953 K, and the aviation kerosene with a flow rate of 12 g / s can be vaporized into a gaseous state after flowing through the fuel heat exchange vaporization pipe 113, and the temperature can reach 523 K. The high-temperature exhaust gas after power is applied exchanges heat with the fuel heat exchange vaporization pipe 113, which fully heats and vaporizes the fuel in the fuel heat exchange vaporization pipe 113, thus completing energy recovery and realizing the cascade utilization of energy.
[0025] Specifically, the baffle plate 2 has multiple igniter mounting holes 12 arranged in a ring array, and an igniter is installed in the igniter mounting hole 12; the ring flame tube 6 is ignited and burned through the igniter in the igniter mounting hole 12.
[0026] Specifically, multiple support plates 13 are fixed to the inner wall of the turbine exhaust channel 4, and a pneumatic cone 14 is fixed to the end of the support plate 13; the pneumatic cone 14 assists the flow of high-pressure airflow.
[0027] It should be noted that, in this document, the terms “comprising,” “including,” or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such process, method, article, or apparatus.
[0028] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.
Claims
1. A fully premixed annular combustion chamber based on metal fiber cloth, comprising a combustion chamber shell (1), characterized in that: A baffle plate (2) is fixedly connected to the inner end of the combustion chamber shell (1). A partition plate (3) extending into the interior of the combustion chamber shell (1) is fixedly connected to the inner edge of the baffle plate (2). The inner side of the partition plate (3) is a turbine exhaust channel (4) for discharging high-temperature exhaust gas. A combustion chamber (5) is formed between the outer side of the partition plate (3) and the inner wall of the combustion chamber shell (1). A hollow annular flame tube (6) for ignition and combustion is fixedly connected inside the combustion chamber (5). A guide for the rotation of the premixed gas flow is installed at the inner end of the annular flame tube (6). The inner walls of the upper and lower sides of the annular flame tube (6) are welded with metal fiber cloth (8) for preheating and premixing gas. The upper wall of the annular flame tube (6) and the inner wall of the combustion chamber shell (1) form the outer side flow channel (9) of the combustion chamber. The lower wall of the annular flame tube (6) and the outer wall of the partition plate (3) form the inner side flow channel (10) of the combustion chamber. The tail end of the inner side flow channel (10) of the combustion chamber is a closed structure. The baffle plate (2) is equipped with a fuel gasification system (11) for supplying gasified fuel for combustion.
2. The fully premixed annular combustion chamber based on metal fiber cloth according to claim 1, characterized in that: The metal components in the combustion chamber shell (1) are all made of GH3625 nickel-chromium-molybdenum-niobium solid solution strengthened high-temperature alloy.
3. The fully premixed annular combustion chamber based on metal fiber cloth according to claim 1, characterized in that: The inner walls of the upper and lower sides of the annular flame tube (6) are provided with permeation holes, and the deflection channel (7) is provided with a deflection hole that communicates with the inner side channel (10) of the combustion chamber. The porosity of the deflection channel (7) is greater than that of the annular flame tube (6).
4. The fully premixed annular combustion chamber based on metal fiber cloth according to claim 1, characterized in that: The metal fiber cloth (8) is made of iron-chromium-aluminum metal fiber cloth, and the iron-chromium-aluminum metal fiber cloth is a three-dimensional porous material.
5. The fully premixed annular combustion chamber based on metal fiber cloth according to claim 1, characterized in that: The fuel vaporization system (11) includes a liquid fuel manifold (111) and a vaporized fuel manifold (112) opened in the baffle plate (2), and the vaporized fuel manifold (112) is located inside the liquid fuel manifold (111). Multiple fuel heat exchange vaporization pipes (113) are fixedly connected in a ring array on the liquid fuel manifold (111), and the ends of the fuel heat exchange vaporization pipes (113) extend into the vaporized fuel manifold (112). The baffle plate (2) is respectively fixed with a liquid fuel injection port (114) extending into the liquid fuel manifold (111) and a gaseous fuel outlet (115) extending into the vaporized fuel manifold (112).
6. A fully premixed annular combustion chamber based on metal fiber cloth according to claim 5, characterized in that: The fuel heat exchange vaporization pipe (113) is installed in a U-shape on the inner wall of the turbine exhaust channel (4). Its flow path is from the head to the tail of the turbine exhaust channel (4), and then back to the head to inject the vaporized fuel manifold (112).
7. A fully premixed annular combustion chamber based on metal fiber cloth according to claim 1, characterized in that: The sealing plate (2) has multiple igniter mounting holes (12) arranged in a ring array, and an igniter is installed in the igniter mounting holes (12).
8. A fully premixed annular combustion chamber based on metal fiber cloth according to claim 1, characterized in that: The inner wall of the turbine exhaust channel (4) is fixed with multiple support plates (13), and the end of the support plate (13) is fixed with a pneumatic cone (14).