Anti-flashback nozzles and gas turbines

Abstract

The present invention discloses an anti-flashback nozzle and a gas turbine, wherein the anti-flashback nozzle comprises a nozzle body and an adjusting member, wherein the nozzle body has a fuel channel and a plurality of fuel spray holes, the fuel spray holes are connected to the fuel channel, and the adjusting member is arranged in the fuel spray holes to adjust the flow area of ​​the fuel spray holes, and the gas turbine comprises an anti-flashback nozzle. When flashback occurs, the adjusting member expands and deforms, and the adjusting member reduces the flow area of ​​the fuel spray holes, thereby reducing the fuel flow rate to prevent the flashback from further deteriorating, thereby playing a role in flashback protection. When the flashback is eliminated, the adjusting member shrinks and deforms to a normal shape, and the flow area of ​​the fuel spray holes returns to a normal size, and the fuel flow rate is adjusted back. Thus, the complex flashback protection method of sensor feedback control is effectively replaced, and the difficulties caused by arranging sensors in the narrow space of the combustion chamber nozzle and the problem of flashback protection reliability caused by the sensors are avoided.

Description

Technical Field

[0001] The invention relates to the technical field of gas turbines, and in particular to an anti-flashback nozzle and a gas turbine. Background Art

[0002] As the global carbon neutrality process accelerates, gas turbines with hydrogen combustion capabilities are the current research and development focus of various gas turbine manufacturers. The development of hydrogen-mixed / pure hydrogen gas turbines can, on the one hand, resolve energy security issues, and on the other hand, alleviate the resistance to the development of the gas turbine industry caused by natural gas shortages. It will play a key supporting role in "building a new power system with new energy as the main body."

[0003] Compared with traditional natural gas fuel, the addition of hydrogen will cause significant changes in the physical and chemical properties of the fuel. Hydrogen will broaden the flammable range of traditional hydrocarbon fuels, accelerate the flame propagation speed of the fuel, increase the combustion speed in turbulent combustion of the fuel, and the minimum ignition energy will be lower and easier to self-ignite. The most significant impact of these changes on the gas turbine is that its combustion chamber is more prone to flashback.

[0004] In the related art, the main means of flashback protection are: arranging temperature sensors, static pressure sensors or optical sensors, etc., and judging flashback through feedback signals to distribute fuel, control fuel quantity, etc. However, it is difficult to arrange sensors in the narrow space of the combustion chamber nozzle, and it is also necessary to consider the reliability of flashback protection caused by the lack of monitoring sensitivity of static pressure sensors, the fragility of temperature sensors, and the high cost and fragility of optical sensors. Summary of the invention

[0005] The present invention is based on the inventor's discovery and understanding of the following facts and problems:

[0006] Flashback refers to the phenomenon that under certain combustion conditions, the flame propagates to the upstream of the mixture passage in the fuel nozzle of the combustion chamber. When flashback occurs in the combustion chamber, it will not only seriously damage the combustion chamber components, but also increase the emission of pollutants.

[0007] Therefore, in the related art, corresponding sensors are usually arranged on the running combustion chamber to monitor the flashback to protect the safety of the gas turbine combustion chamber. In the patent of CN101876434A, a method of arranging multiple static pressure sensors on a certain cross section of the premixing channel of the fuel nozzle is used to detect and determine the flashback. If the risk of flashback occurs, the fuel amount of the nozzle will be reduced or the gas turbine output will be reduced to protect the further occurrence of flashback. However, some flashback tests have proved that the sensitivity of flashback to temperature is much higher than that to speed. Therefore, in the patent of CN104534474B, it is believed that the method of using temperature sensors to detect flashback is more appropriate, but the temperature sensor is more easily damaged, which affects the reliability of monitoring. In the patents of CN101846317A and CN102235674A, optical sensors are used to detect flashback. It is necessary to arrange multiple different optical sensors to monitor the flame wavelengths in different combustion areas and then detect flashback. However, optical sensors are relatively expensive and easily damaged in high temperature environments.

[0008] The present invention aims to solve one of the technical problems in the related art at least to a certain extent.

[0009] To this end, an embodiment of the present invention provides an anti-flashback nozzle, which has the function of automatically adjusting the fuel flow rate.

[0010] An embodiment of the present invention further provides a gas turbine, the flashback protection method of the gas turbine is relatively simple.

[0011] The anti-flashback nozzle of an embodiment of the present invention includes a nozzle body and an adjusting part, the nozzle body has a fuel channel and a plurality of fuel spray holes, the fuel spray holes are connected to the fuel channel, the adjusting part is arranged in the fuel spray holes, the adjusting part can expand and deform to reduce the flow area of ​​the fuel spray holes when the temperature is higher than the protection temperature, and the adjusting part can shrink and deform to expand the flow area of ​​the fuel spray holes when the temperature is lower than the protection temperature.

[0012] The anti-flashback nozzle of the embodiment of the present invention is provided with an adjusting part in the fuel nozzle hole. When flashback occurs, the temperature of the adjusting part rises. When it exceeds the protection temperature, the adjusting part expands and deforms, and the adjusting part reduces the flow area of ​​the fuel nozzle hole, thereby reducing the fuel flow rate to prevent the flashback from further deteriorating, thereby playing the role of flashback protection. When the flashback is eliminated, the temperature of the adjusting part drops to below the protection temperature, and the adjusting part shrinks and deforms to a normal shape, so that the flow area of ​​the fuel nozzle hole returns to a normal size and the fuel flow rate is adjusted back. Therefore, the anti-flashback nozzle of the embodiment of the present invention effectively replaces the complex flashback protection method of sensor feedback control, avoiding the difficulties caused by arranging sensors in the narrow space of the combustion chamber nozzle and the problem of flashback protection reliability caused by the sensors.

[0013] In some embodiments, an extending direction of the fuel injection hole is perpendicular to an extending direction of the fuel channel.

[0014] In some embodiments, the plurality of fuel injection holes are spaced apart and distributed along an extending direction of the fuel channel.

[0015] In some embodiments, the adjusting member is cylindrical, and an outer peripheral wall of the adjusting member is connected to a hole wall of the fuel injection hole.

[0016] In some embodiments, the outer peripheral wall of the adjusting member fits with the hole wall of the fuel injection hole.

[0017] In some embodiments, the wall thickness of the adjusting member is 1 to 5 mm.

[0018] In some embodiments, the diameter of the central through hole of the adjusting member is 0.1-2 mm.

[0019] In some embodiments, the adjusting member is made of shape memory alloy.

[0020] The gas turbine according to the embodiment of the present invention comprises the anti-flashback nozzle described in any one of the above embodiments. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 It is a schematic diagram when the temperature of the adjusting part of the anti-flashback nozzle according to the embodiment of the present invention is lower than the protection temperature.

[0022] Figure 2 It is a schematic diagram when the temperature of the adjusting part of the anti-flashback nozzle according to the embodiment of the present invention is higher than the protection temperature.

[0023] Figure 3 is a schematic diagram of a nozzle having a swirl effect.

[0024] Figure 4 is a schematic diagram of a swirl blade of a nozzle having a swirl effect.

[0025] Reference numerals:

[0026] Nozzle body 11, fuel channel 101, fuel injection hole 102, adjustment member 12,

[0027] Inner cylinder 21 , outer cylinder 22 , and swirl blades 23 . DETAILED DESCRIPTION

[0028] Embodiments of the present invention are described in detail below, and examples of the embodiments are shown in the accompanying drawings. The embodiments described below with reference to the accompanying drawings are exemplary and intended to be used to explain the present invention, but should not be understood as limiting the present invention.

[0029] The anti-flashback nozzle according to the embodiment of the present invention will be described below with reference to the accompanying drawings.

[0030] like Figure 1 and Figure 2 As shown, the anti-flashback nozzle of the embodiment of the present invention comprises a nozzle body 11 and an adjusting member 12, wherein the nozzle body 11 has a fuel channel 101 and a plurality of fuel spray holes 102, and the fuel spray holes 102 are connected to the fuel channel 101. The adjusting member 12 is arranged in the fuel spray holes 102, and the adjusting member 12 can expand and deform to reduce the flow area of ​​the fuel spray holes 102 when the temperature is higher than the protection temperature, and can shrink and deform to expand the flow area of ​​the fuel spray holes 102 when the temperature is lower than the protection temperature.

[0031] It can be understood that the multiple fuel nozzles 102 are all connected to the fuel channel 101, so that after the anti-flashback nozzle of the embodiment of the present invention is installed on the gas turbine, the mixed gas fuel mixed with hydrogen can pass through the fuel channel 101 on the nozzle body 11 and be sprayed into the downstream combustion chamber through each fuel nozzle hole 102.

[0032] The addition of hydrogen will cause significant changes in the physical and chemical properties of the fuel. Hydrogen will broaden the flammable range of traditional hydrocarbon fuels, accelerate the flame propagation speed of the fuel, increase the combustion speed in turbulent combustion of the fuel, and the minimum ignition energy will be lower and more prone to spontaneous combustion. The most significant impact of these changes on gas turbines is the increased probability of flashback in their combustion chambers.

[0033] Therefore, the regulating member 12 is arranged in the fuel injection hole 102. Figure 2 As shown, when flashback occurs, the temperature of the adjusting member 12 exceeds the preset protection temperature, and the adjusting member 12 automatically expands according to the temperature to adjust the flow area of ​​the fuel nozzle 102, thereby reducing the flow area of ​​the fuel nozzle 102, thereby regulating the fuel flow rate, and preventing the further deterioration of the flashback by reducing the fuel flow rate, thereby achieving the effect of flashback protection, avoiding flashback from damaging the components in the combustion chamber and increasing the emission of pollutants.

[0034] After the tempering is eliminated, Figure 1 As shown, the regulating member 12 shrinks and deforms to a normal shape to increase the flow area of ​​the fuel injection hole 102, so that the flow area of ​​the fuel injection hole 102 is restored to a normal size and the fuel flow rate is adjusted back.

[0035] Compared with the related art, a temperature sensor, a static pressure sensor or an optical sensor is arranged at the nozzle of the combustion chamber, and the method of fuel distribution and fuel quantity control is performed after judging the flashback through the feedback signal. In the anti-flashback nozzle of the embodiment of the present invention, the adjustment member 12 automatically adjusts the flow area of ​​the fuel nozzle 102 according to the temperature to eliminate the flashback, which effectively replaces the complex flashback protection method of sensor feedback control, simplifies the design process of the gas turbine combustion chamber, and avoids the difficulties caused by arranging various sensors in the narrow space of the combustion chamber nozzle. In addition, there is no problem of flashback protection reliability caused by the insufficient monitoring sensitivity of the static pressure sensor, the easy damage of the temperature sensor, and the high cost and easy damage of the optical means in the existing feedback control method.

[0036] Moreover, the protection temperature of the gas turbine is set differently under different working conditions. Moreover, when the combustion chamber is operating normally, the premixing channel of the combustion chamber nozzle contains a mixture of air and fuel, and its temperature is significantly lower than the temperature of the burned area in the combustion chamber. When flashback occurs, the temperature of the premixing channel of the nozzle is significantly higher than the normal temperature due to flashback, causing the temperature of the regulating member 12 to rise above the normal temperature, and then expansion and deformation occurs.

[0037] For example, if the protection temperature is set to 700°C. When flashback occurs, after the temperature of the adjusting member 12 exceeds 700°C, the adjusting member 12 expands and deforms to reduce the flow area of ​​the fuel injection hole 102, thereby reducing the fuel flow rate and performing flashback protection. When the flashback is eliminated, the temperature of the adjusting member 12 drops below 700°C, and the adjusting member 12 shrinks and deforms to a normal shape to increase the flow area of ​​the fuel injection hole 102, so that the flow area of ​​the fuel injection hole 102 is restored to a normal size, and the fuel flow rate is adjusted back.

[0038] Optionally, the adjusting member 12 may be provided in only one or a few (less than the number of the fuel injection holes 102) of the plurality of fuel injection holes 102. Alternatively, an adjusting member 12 may be provided in each fuel injection hole 102. According to the actual requirements of the working conditions, if the flashback can be eliminated by changing the flow area of ​​some fuel injection holes 102, the adjusting member 12 is provided in some fuel injection holes 102. If the flashback needs to be eliminated as soon as possible, the adjusting member 12 may be provided in each fuel injection hole 102, thereby increasing the flashback elimination efficiency.

[0039] Specifically, there are a plurality of adjusting members 12 , and the plurality of adjusting members 12 correspond one-to-one to the plurality of fuel injection holes 102 , and each adjusting member 12 is installed in the fuel injection hole 102 corresponding thereto.

[0040] Therefore, the anti-flashback nozzle of the embodiment of the present invention sets an adjustment member 12 in the fuel nozzle hole 102. When flashback occurs, the temperature of the adjustment member 12 rises. When it exceeds the protection temperature, the adjustment member 12 expands and deforms. The adjustment member 12 reduces the flow area of ​​the fuel nozzle hole 102, thereby reducing the fuel flow rate to prevent the flashback from further deteriorating, thereby playing a role in flashback protection. When the flashback is eliminated, the temperature of the adjustment member 12 drops to below the protection temperature, and the adjustment member 12 shrinks and deforms to a normal shape, so that the flow area of ​​the fuel nozzle hole returns to a normal size and the fuel flow rate is adjusted back. Therefore, the anti-flashback nozzle of the embodiment of the present invention effectively replaces the complex flashback protection method of sensor feedback control, avoiding the difficulties caused by arranging sensors in the narrow space of the combustion chamber nozzle and the problem of reliability of flashback protection caused by the sensors.

[0041] In some embodiments, Figure 1 or Figure 2 As shown, the extending direction of the fuel injection hole 102 is perpendicular to the extending direction of the fuel channel 101 .

[0042] In some embodiments, the plurality of fuel injection holes 102 are spaced apart and distributed along the extending direction of the fuel channel 101 .

[0043] In some embodiments, Figure 1 and Figure 2 As shown, the adjusting member 12 is cylindrical, and the outer peripheral wall of the adjusting member 12 is connected to the hole wall of the fuel injection hole 102 .

[0044] Alternatively, if Figures 1 to 3 As shown, the adjusting member 12 is cylindrical, and the central axis of the adjusting member 12 is coaxially arranged with the central axis of the fuel injection hole 102. Both ends of the adjusting member 12 along its own axial direction are flush with both ends of the fuel injection hole 102 along its own axial direction.

[0045] Furthermore, the outer peripheral wall of the adjusting member 12 is connected to the hole wall of the fuel injection hole 102 by welding, and the outer peripheral wall of the adjusting member 12 is in contact with the hole wall of the fuel injection hole 102 .

[0046] It can be understood that, since the two ends of the adjusting member 12 are flush with the two ends of the fuel injection hole 102, and the outer peripheral wall of the adjusting member 12 is in contact with the hole wall of the fuel injection hole 102, the central through hole of the adjusting member 12 is connected to the fuel channel 101, and the change of the flow area of ​​the fuel injection hole 102 in the above embodiment is to change the flow area of ​​the central through hole of the adjusting member 12.

[0047] In some embodiments, the wall thickness of the adjusting member 12 is 1-5 mm.

[0048] It is understandable that the wall thickness of the adjusting member 12 refers to the distance between the inner peripheral wall of the adjusting member 12 and the outer peripheral wall of the adjusting member 12. Optionally, the wall thickness of the adjusting member 12 is 1 mm, 2 mm, 3 mm, 4 mm or 5 mm. Moreover, different thicknesses correspond to different expansion ranges of the adjusting member 12. The greater the wall thickness of the adjusting member 12, the greater its expansion range. Conversely, the smaller the wall thickness of the adjusting member 12, the smaller its expansion range.

[0049] In some embodiments, the diameter of the central through hole of the adjusting member 12 is 0.1-2 mm.

[0050] Optionally, the diameter of the central through hole of the adjusting member 12 is 0.1 mm, 0.5 mm, 1 mm, 1.5 mm or 2 mm. It is understood that when operating normally, Figure 2 As shown, the central through hole of the adjusting member 12 is a passage of a normal cylindrical hole. Figure 3 As shown, the adjusting member 12 expands inwardly to reduce the flow area of ​​the central through hole of the adjusting member 12. The deformation degree of the two ends of the central through hole of the adjusting member 12 along its axial direction is small, and the expansion deformation degree of the middle part is the largest.

[0051] Furthermore, when tempering occurs, the aperture of the middle portion of the central through hole of the adjusting member 12 becomes 5%-50% of the normal aperture.

[0052] In some embodiments, the material of the adjusting member 12 is a shape memory alloy, such as a TiNi-based shape memory alloy, a copper-based shape memory alloy, an iron-based shape memory alloy, and the like.

[0053] Therefore, by utilizing the deformation characteristics of shape memory alloy at different temperatures, the adjustment member 12 can automatically adjust the aperture of the fuel injection hole 102 according to the temperature, thereby controlling the fuel supply to protect the gas turbine combustion chamber from flashback.

[0054] In addition, the regulating member according to the embodiment of the present invention can be applied to the gas holes of different types of nozzles. A nozzle with a swirl effect is specifically listed below.

[0055] like Figure 3 and Figure 4As shown, the nozzle includes: an inner cylinder 21, an outer cylinder 22 and a plurality of swirl blades 23. The outer cylinder 22 is sleeved outside the inner cylinder 21, the outer cylinder 22 and the inner cylinder 21 are spaced apart in the inner and outer directions, and the central axis of the inner cylinder 21 is coaxially arranged with the central axis of the outer cylinder 22. The swirl blades 23 are arranged between the inner cylinder 21 and the outer cylinder 22, the blade roots of the swirl blades 23 (the end of the swirl blades 23 close to the inner cylinder 21) are connected to the outer peripheral wall of the inner cylinder 21, the blade tops of the swirl blades 23 (the end of the swirl blades 23 close to the outer cylinder 22) are connected to the inner peripheral wall of the outer cylinder 22, and the plurality of swirl blades 23 are spaced and distributed along the circumference of the inner cylinder 21.

[0056] The fuel channel 101 is provided on the swirl blade 23, and the fuel channel 101 extends from the root of the swirl blade 23 to the tip of the swirl blade 23. A plurality of fuel injection holes 102 are provided on the suction surface of the swirl blade 23, and are close to the leading edge of the swirl blade 23. The fuel injection holes 102 extend from the suction surface of the swirl blade 23 to the pressure surface of the swirl blade 23, and the extension direction of the fuel injection holes 102 is perpendicular to the extension direction of the fuel channel 101, and the plurality of fuel injection holes 102 are distributed at intervals along the extension direction of the fuel channel 101.

[0057] It should be understood that the suction surface of the swirl blade 23 refers to the concave surface of the swirl blade 23, and the pressure surface of the swirl blade 23 refers to the convex surface of the swirl blade 23. Multiple fuel injection holes 102 are evenly distributed on the suction surface of the swirl blade 23 so that the mixed gas of air and fuel is evenly injected into the combustion chamber.

[0058] Therefore, by providing an adjustment member 12 made of shape memory alloy in the fuel injection hole 102 on the swirl blade 23, the adjustment member 12 can automatically adjust the fuel flow rate of the fuel injection hole 102 when flashback occurs, so that the nozzle has a flashback protection function.

[0059] The gas turbine according to the embodiment of the present invention comprises the anti-flashback nozzle according to the above embodiment.

[0060] The gas turbine of the embodiment of the present invention protects the gas turbine combustion chamber from flashback by using a method of fully automatically adjusting the fuel supply using a deformation memory alloy, effectively replacing the complex flashback protection method of sensor feedback control in the related art, simplifying the design process of the gas turbine combustion chamber, and avoiding the difficulty of arranging various sensors in the narrow space of the combustion chamber nozzle. In addition, there is no problem of flashback protection reliability caused by the static pressure sensor's insufficient monitoring sensitivity, the temperature sensor's easy damage, and the optical means' high cost and easy damage in the existing feedback control method, and the flashback protection method of the gas turbine is relatively simple.

[0061] In the description of the present invention, it is to be understood that the terms “center”, “longitudinal”, “lateral”, “length”, “width”, “thickness”, “up”, “down”, “front”, “back”, “left”, “right”, “vertical”, “horizontal”, “top”, “bottom”, “inside”, “outside”, “clockwise”, “counterclockwise”, “axial”, “radial”, “circumferential”, etc., indicating orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the referred device or element must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as limiting the present invention.

[0062] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include at least one of the features. In the description of the present invention, the meaning of "plurality" is at least two, such as two, three, etc., unless otherwise clearly and specifically defined.

[0063] In the present invention, unless otherwise clearly specified and limited, the terms "installed", "connected", "connected", "fixed" and the like should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral one; it can be a mechanical connection, an electrical connection, or communication with each other; it can be a direct connection, or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements, unless otherwise clearly defined. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0064] In the present invention, unless otherwise clearly specified and limited, a first feature being "above" or "below" a second feature may mean that the first and second features are in direct contact, or the first and second features are in indirect contact through an intermediate medium. Moreover, a first feature being "above", "above" or "above" a second feature may mean that the first feature is directly above or obliquely above the second feature, or simply means that the first feature is higher in level than the second feature. A first feature being "below", "below" or "below" a second feature may mean that the first feature is directly below or obliquely below the second feature, or simply means that the first feature is lower in level than the second feature.

[0065] In the present invention, the terms "one embodiment", "some embodiments", "examples", "specific examples", or "some examples" etc. mean that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the described specific features, structures, materials or characteristics may be combined in any one or more embodiments or examples in a suitable manner. In addition, those skilled in the art may combine and combine the different embodiments or examples described in this specification and the features of the different embodiments or examples, without contradiction.

[0066] Although the above embodiments have been shown and described, it is to be understood that the above embodiments are exemplary and are not to be construed as limitations on the present invention. Changes, modifications, substitutions and variations of the above embodiments by those of ordinary skill in the art are all within the scope of protection of the present invention.

Claims

1. A flashback prevention nozzle, characterized in that: include: a nozzle body, the nozzle body having a fuel passage and a plurality of fuel injection holes, the fuel injection holes being connected to the fuel passage; and, The regulating member is arranged in the fuel injection hole. When the temperature of the regulating member is higher than the protection temperature, the regulating member can expand and deform to reduce the flow area of ​​the fuel injection hole. When the temperature of the regulating member is lower than the protection temperature, the regulating member can shrink and deform to expand the flow area of ​​the fuel injection hole.

2. The anti-flashback nozzle according to claim 1, characterized in that: An extending direction of the fuel injection hole is perpendicular to an extending direction of the fuel channel.

3. The anti-flashback nozzle according to claim 2, characterized in that: The plurality of fuel injection holes are distributed at intervals along an extending direction of the fuel channel.

4. The anti-flashback nozzle according to claim 1, characterized in that: The adjusting member is cylindrical, and the outer peripheral wall of the adjusting member is connected to the hole wall of the fuel injection hole.

5. The anti-flashback nozzle according to claim 4, characterized in that: The outer peripheral wall of the adjusting member is in contact with the hole wall of the fuel injection hole.

6. The anti-flashback nozzle according to claim 1, characterized in that: The wall thickness of the adjusting member is 1-5 mm.

7. The anti-flashback nozzle according to claim 1, characterized in that: The diameter of the central through hole of the adjusting member is 0.1-2 mm.

8. The anti-flashback nozzle according to claim 1, characterized in that: The material of the adjusting member is shape memory alloy.

9. A gas turbine, characterized in that: The invention comprises the anti-flashback nozzle according to any one of claims 1 to 8.

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