Double-channel single-jet anti-carbon-depositing fuel nozzle with check valve

Abstract

The present application aims to provide a double-channel single-nozzle anti-carbon-deposition fuel nozzle with a check valve, belonging to the field of gas turbines, comprising a nozzle body, a check valve and a swirler, the nozzle body is provided with a first channel and a second channel, the swirler is arranged at the end of the first channel, the check valve is arranged at the end of the second channel, the check valve is coaxially arranged and connected with the swirler, the outlet of the swirler is connected with the nozzle, the fuel in the first channel is sprayed through the swirler and the nozzle, and is separated from the second channel under the action of the check valve, and the fluid in the second channel enters the swirler through the check valve. The second channel of the nozzle of the present application is provided with a check valve, which prevents the backflow of fuel, when the working medium in the first channel is fuel, the second channel provides auxiliary atomizing air, which interacts with the swirling air at the nozzle, so as to increase the atomizing cone angle, shorten the fuel penetration distance, improve the fuel atomizing quality, increase the residence time of the fuel in the main combustion zone, and effectively improve the combustion efficiency.

Description

Technical Field

[0001] The present invention relates to a fuel injection device, specifically a gas turbine fuel injection device. Background Technology

[0002] With the continuous development of modern gas turbine technology, the performance of the combustion chamber fuel injection system is crucial. Traditional fuel nozzles have some problems during use. During gas turbine operation, fuel atomization quality and stability affect combustion efficiency. For dual-nozzle injectors, carbon buildup is prone to occur. Carbon buildup interferes with the fuel injection pattern, causing changes in fuel flow rate and injection angle, thus affecting fuel atomization quality and reducing combustion chamber efficiency. When the gas turbine combustion chamber operates under reduced conditions, fuel backflow may occur in the combustion chamber fuel supply system. This not only affects the next normal injection by the nozzle but may also lead to carbon buildup at the nozzle. Summary of the Invention

[0003] The purpose of this invention is to provide a dual-channel, single-nozzle fuel nozzle with a check valve that prevents carbon buildup and enables efficient and stable combustion in the combustion chamber of a gas turbine under all operating conditions.

[0004] The objective of this invention is achieved as follows:

[0005] This invention discloses a dual-channel single-nozzle fuel nozzle with a check valve for preventing carbon buildup. The nozzle nozzle comprises a nozzle body, a check valve, and a swirler. A first channel and a second channel are respectively provided within the nozzle body. The swirler is located at the end of the first channel, and the check valve is located at the end of the second channel. The check valve is connected to the swirler and coaxially arranged. The outlet of the swirler is connected to the nozzle. Fuel from the first channel is ejected through the swirler and the nozzle, and is isolated from the second channel by the check valve. Fluid from the second channel enters the swirler through the check valve.

[0006] The present invention may also include:

[0007] 1. The check valve includes an outer shell, an inner shell, a steel ball, a ball seat, a valve seat, and a spring. The end of the inner shell extends into the outer shell. The ball seat and the valve seat are installed in the inner shell. A spring is installed between the ball seat and the valve seat. A steel ball is installed between the ball seat and the outer shell. A channel A is formed between the ball seat, the valve seat, and the inner shell. The cyclone separator is located in the inner shell. A channel B is provided on the nozzle body outside the nozzle. A heat insulation cover is installed outside the nozzle body at this location. The space formed by the heat insulation cover and the nozzle body is connected to the nozzle B. The nozzle B is connected to the nozzle.

[0008] 2. When the gas turbine is running at low operating conditions, fuel oil flows into the first channel and auxiliary atomizing air flows into the second channel. The auxiliary atomizing air is pressurized and sheared with the fuel oil through the check valve and swirler.

[0009] 3. When the gas turbine is in operation, fuel flows into the first channel and auxiliary atomizing air flows into the second channel. The atomizing air in channel B rotates in the opposite direction to the atomizing air in the second channel. The atomizing air with the opposite rotation direction is on both sides of the fuel atomizing cone.

[0010] 4. When the gas turbine increases its operating condition from a low operating condition, the second channel changes from flowing into auxiliary atomizing air to flowing into fuel. The fuel in the second channel, after passing through the check valve, merges with the fuel in the first channel in the nozzle and is then sprayed out.

[0011] 5. On the nozzle body, a first cap is installed at the end of the first channel, and a first channel filter is installed below the first cap. A second cap is installed at the end of the second channel, and a second channel filter is installed below the second cap.

[0012] 6. A third cap is provided at the end of the outer casing.

[0013] The advantages of this invention are as follows: This invention employs a tiered treatment of the fuel passage in the anti-carbon-deposit fuel nozzle. Specifically, when the gas turbine is operating at low speeds, nozzle channel I injects fuel, while the auxiliary atomizing air in nozzle channel II, combined with the swirling atomizing air at the nozzle opening, enhances the secondary breakup of fuel droplets, improving the atomization characteristics of the fuel in channel I and the combustion stability of the combustion chamber. This invention's dual-channel, single-nozzle anti-carbon-deposit fuel nozzle with a check valve can achieve efficient and stable combustion in the gas turbine combustion chamber under all operating conditions. The filter and check valve are easy to maintain and disassemble, significantly improving nozzle maintenance efficiency and possessing significant application value. Attached Figure Description

[0014] Figure 1 This is a schematic diagram of the structure of the present invention;

[0015] Figure 2 for Figure 1 View A in the middle;

[0016] Figure 3 A schematic diagram of a stop valve. Detailed Implementation

[0017] The invention will now be described in more detail with reference to the accompanying drawings:

[0018] Combination Figure 1-3 The present invention mainly includes a plug cap 1, a channel I filter 2, a cyclone separator 3, a nozzle 4, a heat shield 5, a check valve 6, a plug cap 7, a channel II filter 8, a plug cap 9, a steel ball 10, a ball seat 11, a spring 12, and a valve seat 13. The nozzle 4, cyclone separator 3, and check valve 6 are arranged coaxially. Auxiliary atomized air or fuel from channel II enters the combustion zone of the combustion chamber through the check valve 6, cyclone separator 3, and nozzle 4.

[0019] When fuel flows in from channel I, auxiliary atomizing air flows in from channel II. The air passes through check valve 6 and swirler 3, where it is pressurized and sheared against the fuel, improving the atomization characteristics of the liquid fuel. The atomizing air in channel II flows past the center of the fuel atomization cone, increasing the atomization cone angle, shortening the fuel penetration distance, and increasing the residence time of the fuel in the main combustion zone of the combustion chamber, thereby improving fuel combustion efficiency. The application of check valve 6 also prevents liquid fuel from channel I from entering channel II.

[0020] When fuel flows in from the inlet of channel I and auxiliary atomizing air flows in from channel II, and air from the combustion chamber flows in through channel B, the two flow directions are opposite. The two streams of atomizing air are on both sides of the fuel atomizing cone. The opposite swirling directions increase the force between the air and the atomizing cone, thereby improving the fuel atomization performance.

[0021] When fuel flows in from the inlet of channel I, as the operating conditions of the gas turbine increase, the required amount of fuel increases, and fuel flows in from the inlet of channel II. The check valve 6 opens, and the fuel flows through channel A. After strong swirling in the swirler 3, it merges with the fuel from channel I in the nozzle and enters the combustion zone of the combustion chamber.

[0022] When the gas turbine is operating under reduced operating conditions, the fuel flow rate in channel II gradually decreases until the check valve closes. After closure, no more fuel will be injected into the combustion chamber from channel II. Check valve 6 effectively prevents fuel backflow, protecting the nozzles and the entire fuel system.

[0023] The advantage of the dual-channel single-nozzle nozzle is that fuel is always injected into the nozzle 4 under any operating conditions, effectively preventing fuel backflow and carbon buildup in the II channel.

[0024] When the gas turbine is operating under high conditions, the use of heat shield 5 can effectively block heat transfer from the main combustion zone to the nozzle orifice, preventing carbon buildup, coking, and other malfunctions at the nozzle orifice. Removing plugs 1 and 9 allows for cleaning of channel I filter 2 and channel II filter 8, or replacement with new filters. Similarly, the check valve 6 inside nozzle channel II is easy to disassemble and maintain.

[0025] As can be seen from the above working process, this invention provides a dual-channel, single-nozzle fuel injector with a check valve to prevent carbon buildup. Compared with other gas turbine injectors, this structure has a check valve 6 in channel II. When the gas turbine is operating at low conditions, the atomizing air introduced into channel II interacts and shears with the swirling atomizing air in channel B, effectively improving the fuel atomization characteristics, while preventing fuel from flowing back into channel II from channel I. The nozzle cap removal operation is simple, and the filter and check valve 6 are easy to maintain and replace, effectively improving the maintenance efficiency of the fuel injector.

Claims

1. A dual-channel single-nozzle fuel nozzle with a check valve to prevent carbon buildup, characterized in that: The nozzle body includes a nozzle body, a check valve, and a swirler. The nozzle body is provided with a first channel and a second channel. The swirler is located at the end of the first channel, and the check valve is located at the end of the second channel. The check valve is connected to the swirler and is coaxially arranged. The outlet of the swirler is connected to the nozzle. The fuel in the first channel is sprayed out through the swirler and the nozzle, and is isolated from the second channel by the check valve. The fluid in the second channel enters the swirler through the check valve. The check valve includes an outer shell, an inner shell, a steel ball, a ball seat, a valve seat, and a spring. The end of the inner shell extends into the outer shell. The ball seat and the valve seat are installed inside the inner shell. A spring is installed between the ball seat and the valve seat. A steel ball is installed between the ball seat and the outer shell. A channel A is formed between the ball seat, the valve seat, and the inner shell. The cyclone separator is located inside the inner shell. A channel B is provided on the nozzle body outside the nozzle. A heat insulation cover is installed outside the nozzle body at this location. The space formed by the heat insulation cover and the nozzle body is connected to the nozzle B. The nozzle B is connected to the nozzle.

2. A dual-channel single-nozzle anti-carbon-deposit fuel nozzle with a check valve according to claim 1, characterized in that: When the gas turbine is operating at low operating conditions, fuel flows into the first channel and auxiliary atomizing air flows into the second channel. The auxiliary atomizing air is pressurized and sheared with the fuel through the check valve and swirler.

3. A dual-channel single-nozzle anti-carbon-deposit fuel nozzle with a check valve according to claim 1, characterized in that: When the gas turbine is in operation, fuel flows into the first channel and auxiliary atomizing air flows into the second channel. The atomizing air in channel B rotates in the opposite direction to the atomizing air in the second channel. The atomizing air with the opposite rotation direction is on both sides of the fuel atomizing cone.

4. A dual-channel single-nozzle fuel nozzle with a check valve for preventing carbon buildup, as described in claim 1, is characterized in that: When the gas turbine increases its operating condition from a low operating condition, the second channel changes from flowing into auxiliary atomizing air to flowing into fuel. The fuel in the second channel passes through the check valve and then merges with the fuel in the first channel into the nozzle and is sprayed out.

5. A dual-channel single-nozzle fuel nozzle with a check valve for preventing carbon buildup, as described in claim 1, is characterized in that: On the nozzle body, a first cap is installed at the end of the first channel, and a first channel filter is installed below the first cap. A second cap is installed at the end of the second channel, and a second channel filter is installed below the second cap.

6. A dual-channel single-nozzle anti-carbon-deposit fuel nozzle with a check valve according to claim 1, characterized in that: A third cap is provided at the end of the outer casing.

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