Double-channel single-nozzle carbon deposition prevention fuel nozzle with check valve

Abstract

The invention aims to provide a double-channel single-spout carbon deposition prevention fuel nozzle with a check valve, which belongs to the field of gas turbines, and comprises a nozzle body, the check valve and a swirler, a first channel and a second channel are respectively arranged in the nozzle body, the swirler is arranged at the end part of the first channel, the check valve is arranged at the end part of the second channel, and the first channel and the second channel are communicated with each other. The check valve is connected with the swirler and is coaxially arranged, an outlet of the swirler is connected with the nozzle, fuel oil in the first channel is sprayed out through the swirler and the nozzle and is separated from the second channel under the action of the check valve, and fluid in the second channel enters the swirler through the check valve. The channel II of the nozzle is provided with the check valve, fuel oil is prevented from flowing back, when the working medium of the channel I is fuel oil, the channel II provides auxiliary atomization air, and under the interaction of the auxiliary atomization air and rotational flow air at the injection opening, the atomization taper angle can be increased, the fuel oil penetrating distance can be shortened, the fuel oil atomization quality can be improved, the residence time of the fuel oil in a main combustion area is prolonged, and the combustion efficiency is effectively improved.

Description

Technical Field

[0001] The present invention relates to a fuel injection device, in particular to a fuel injection device for a gas turbine. Background Art

[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. When the gas turbine is running, the fuel atomization quality and stability affect the combustion efficiency. For dual-nozzle fuel injectors, nozzle carbon deposition is prone to occur. Carbon deposition will interfere with the injection pattern of the fuel, causing changes in the fuel flow rate and injection angle, thereby affecting the atomization quality of the fuel and reducing the combustion efficiency of the combustion chamber. When the gas turbine combustion chamber is operating at reduced operating conditions, fuel backflow may occur in the combustion chamber fuel supply system, which will not only affect the next normal injection of the nozzle, but may also cause carbon deposition of the fuel at the nozzle. Summary of the invention

[0003] The object of the present invention is to provide a dual-channel single-nozzle anti-carbon deposition fuel nozzle with a check valve, which can realize efficient and stable combustion in a gas turbine combustion chamber under all working conditions.

[0004] The object of the present invention is achieved in that:

[0005] The present invention discloses a dual-channel single-nozzle anti-carbon deposition fuel nozzle with a check valve, which is characterized by comprising a nozzle body, a check valve and a swirler, wherein a first channel and a second channel are respectively arranged in the nozzle body, 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 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 cut off 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.

[0006] The present invention may also include:

[0007] 1. The check valve comprises 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 respectively installed in the inner shell. A spring is installed between the ball valve 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 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. The space formed by the heat insulation cover and the nozzle body is connected to the nozzle B, and the nozzle B is connected to the nozzle.

[0008] 2. When the gas turbine is running at low 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 the swirler.

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

[0010] 4. When the gas turbine is operated from a low condition to a high condition, the second channel changes from inflowing auxiliary atomizing air to inflowing fuel. The fuel in the second channel passes through the check valve and is combined with the fuel in the first channel in the nozzle and ejected.

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

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

[0013] The advantages of the present invention are: the present invention performs graded treatment on the fuel channel of the anti-carbon deposition fuel nozzle, and the characteristic is that when the gas turbine is running at low operating conditions, the nozzle I channel works to spray fuel, and the auxiliary atomizing air of the nozzle II channel and the swirl atomizing air at the nozzle port jointly enhance the secondary breakup of the fuel droplets, improve the atomization characteristics of the fuel in the I channel and the combustion stability of the combustion chamber. The dual-channel single-nozzle anti-carbon deposition fuel nozzle with a check valve of the present invention can be used to achieve efficient and stable combustion in the combustion chamber of the gas turbine under all operating conditions, and the maintenance and disassembly of the filter and the check valve are simple, which greatly improves the maintenance efficiency of the nozzle and has important application value. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] Figure 1 It is a structural schematic diagram of the present invention;

[0015] Figure 2 for Figure 1 A-direction view in the figure;

[0016] Figure 3 Schematic diagram of the check valve structure. DETAILED DESCRIPTION

[0017] The present invention is described in more detail below with reference to the accompanying drawings:

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

[0019] When the fuel flows in from the entrance of channel I, auxiliary atomizing air flows into channel II. The air passes through the check valve 6 and the swirler 3 and is pressurized and sheared with the fuel, which improves the atomization characteristics of the liquid fuel. The atomizing air of channel II flows through the center of the fuel atomizing cone, which increases the atomizing cone angle, shortens the fuel penetration distance, and increases the residence time of the fuel in the main combustion zone of the combustion chamber, thereby improving the fuel combustion efficiency. The application of the check valve 6 also prevents the liquid fuel in channel I from entering channel II.

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

[0021] When the 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 the fuel flows in from the inlet of channel II. The check valve 6 opens, and the fuel flows through channel A. After the strong swirl of the swirler 3, it merges with the fuel of channel I in the nozzle and enters the combustion zone of the combustion chamber.

[0022] When the gas turbine is running at the downgrade condition, the fuel flow rate of channel II gradually decreases until the check valve is closed. After closing, no fuel will be sprayed into the combustion chamber from channel II. The check valve 6 effectively prevents the fuel from flowing back, protecting the nozzle and the entire fuel system.

[0023] The advantage of the dual-channel single-nozzle nozzle is that under any operating conditions, fuel is always sprayed out of the nozzle 4, which effectively prevents fuel backflow and carbon deposition in channel II.

[0024] When the gas turbine is running at high operating conditions, the use of the heat shield 5 can effectively block the heat transfer and heat exchange from the main combustion zone to the nozzle nozzle, preventing carbon deposition, coking and other faults from occurring at the nozzle nozzle. The plugging cap 1 and the plugging cap 9 can be removed to clean the I channel filter 2 and the II channel filter 8, or to replace them with new filters. Similarly, the check valve 6 in the nozzle II channel is easy to disassemble and maintain.

[0025] It can be seen from the above working process that the dual-channel single-nozzle anti-carbon deposition fuel nozzle with a check valve of the present invention is compared with other gas turbine nozzles. The check valve 6 is set in the II channel. When the gas turbine is running at low working conditions, the atomizing air put into the II channel interacts with the swirl atomizing air of the channel B to effectively improve the fuel atomization characteristics, and at the same time prevent the fuel from flowing back into the II channel from the I channel. The nozzle plugging cap is easy to disassemble, and the filter and the check valve 6 are easy to repair and replace, which effectively improves the maintenance efficiency of the fuel injector.

Claims

1. A dual-channel single-nozzle anti-carbon deposition fuel nozzle with a check valve, characterized by: The invention comprises a nozzle body, a check valve and a swirler. A first channel and a second channel are respectively arranged in the nozzle body. 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 connected to the swirler and arranged coaxially. 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 cut off from the second channel by the action of the check valve. The fluid in the second channel enters the swirler through the check valve.

2. The dual-channel single-nozzle anti-carbon deposition fuel nozzle with a check valve according to claim 1, characterized in that: The check valve comprises 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 respectively installed in the inner shell. A spring is installed between the ball valve 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 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. The space formed by the heat insulation cover and the nozzle body is connected to the nozzle B, and the nozzle B is connected to the nozzle.

3. The dual-channel single-nozzle anti-carbon deposition fuel nozzle with a check valve according to claim 2, characterized in that: When the gas turbine is running at low 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 the swirler.

4. The dual-channel single-nozzle anti-carbon deposition fuel nozzle with a check valve according to claim 2, characterized in that: When the gas turbine is running, fuel flows into the first channel and auxiliary atomizing air flows into the second channel. The atomizing air rotation direction of channel B is opposite to that of the atomizing air of the second channel, and the atomizing air of opposite rotation directions is on both sides of the fuel atomizing cone.

5. The dual-channel single-nozzle anti-carbon deposition fuel nozzle with a check valve according to claim 2, characterized in that: When the gas turbine is operated from a low operating condition to a high operating condition, the second channel changes from inflowing auxiliary atomizing air to inflowing fuel oil. The fuel oil in the second channel flows through the check valve and is combined with the fuel oil in the first channel in the nozzle and ejected.

6. The dual-channel single-nozzle anti-carbon deposition fuel nozzle with a check valve according to claim 1, characterized in that: On the nozzle body, a first blocking cap is installed at the end of the first channel, a first channel filter is arranged below the first blocking cap, and a second blocking cap is installed at the end of the second channel, a second channel filter is arranged below the second blocking cap.

7. The dual-channel single-nozzle anti-carbon deposition fuel nozzle with a check valve according to claim 2, characterized in that: A third blocking cap is arranged at the end of the outer shell.

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