Elliptical nozzle design method and sample for enhancing uniformity of annular combustor flow field

Abstract

The application belongs to the technical field of combined engine and rocket engine, and discloses a design method and a sample of an elliptical nozzle for enhancing the uniformity of a flow field of an annular combustion chamber. The design method comprises confirming the size of a single-nozzle combustion area; selecting a nozzle type; designing a gas-liquid nozzle; and establishing a uniformity control strategy. The sample is a combined gas-liquid nozzle sample of a central centrifugal type and an outer peripheral pin type, comprising a pin type elliptical nozzle fixed on a mounting seat of a nozzle mounting flange; the inner wall of the pin type elliptical nozzle is provided with a plurality of liquid centrifugal nozzles in the circumferential direction; a plurality of liquid straight-flow injection orifices are arranged on the nozzle outer surface of the pin type elliptical nozzle with equal arc length; and a gas phase injection annular gap is arranged along the circumferential direction of the pin type elliptical nozzle behind the liquid straight-flow injection orifices. The design method and the sample realize the improvement of the uniformity of the flow field of the annular combustion chamber through structural design and parameter optimization, and have engineering practical value.

Description

Technical Field

[0001] This invention belongs to the field of combined engine and rocket engine technology, specifically relating to a design method and prototype of an elliptical nozzle for enhancing the flow field uniformity of an annular combustion chamber. Background Technology

[0002] The annular combustion chamber is a typical structure in the field of combined propulsion or rocket propulsion technology. Currently, the application scenarios of the annular combustion chamber have put forward the technical development requirements for the uniformity of the combustion flow field. At present, there is an urgent need to develop an elliptical nozzle design method and prototype to enhance the uniformity of the flow field in the annular combustion chamber. Summary of the Invention

[0003] One technical problem to be solved by the present invention is to provide a design method for an elliptical nozzle that enhances the uniformity of the flow field in an annular combustion chamber. Another technical problem to be solved by the present invention is to provide a prototype of an elliptical nozzle that enhances the uniformity of the flow field in an annular combustion chamber, so as to overcome the defects of the prior art.

[0004] The elliptical nozzle design method for enhancing the flow field uniformity of the annular combustion chamber according to the present invention includes the following steps: S10. Confirm the size of the single-nozzle combustion zone; Based on the dimensions of the annular combustion chamber, design the number of nozzles, divide the single-nozzle combustion zone, and determine the aspect ratio t of the single-nozzle combustion zone, where t > 1; S20. Select nozzle type; The nozzle should be selected as a gas-liquid type nozzle. A gas-liquid type nozzle refers to a nozzle in which one component is gas and the other component is liquid. Specifically, it includes needle-type gas-liquid nozzles, direct-flow centrifugal gas-liquid nozzles, and combined gas-liquid nozzles of the center centrifugal type and the outer peripheral needle-type. S30. Design a gas-liquid type nozzle; The gas-liquid nozzle design includes a needle-type gas-liquid nozzle design, a direct-flow centrifugal gas-liquid nozzle design, and a combined gas-liquid nozzle design combining a central centrifugal nozzle and a peripheral needle-type nozzle. Specifically, the needle-type gas-liquid nozzle has a liquid-centered radial nozzle at its center, with multiple circumferentially distributed injection orifices at the front end of the needle, and a gas-phase injection annular slit on its outer periphery. The direct-flow centrifugal gas-liquid nozzle has a liquid-centrifugal nozzle at its center, with a gas-phase injection annular slit on its outer periphery. The combined gas-liquid nozzle combining a central centrifugal nozzle and a peripheral needle-type nozzle has a liquid-centrifugal nozzle in its inner center, a liquid-centered radial nozzle in its outer center, and a gas-phase injection annular slit on its outer periphery. During the design process, the needle plug was optimized from a circular structure to an elliptical structure; S40. Establish a uniformity control strategy; For the elliptical structure, the flow distribution scheme of the gas-liquid nozzle was adjusted through simulation calculation and experimental verification, the nozzle structural parameters were optimized, and a uniformity control strategy was established to achieve a uniform flow field in the annular combustion chamber and improve combustion efficiency.

[0005] Furthermore, the specific process of S10 is as follows: Based on the dimensions of the annular combustion chamber, determine the inner diameter d2 and outer diameter d1 of the annular combustion chamber, and then determine the number of nozzles n. Calculate the basic dimensions of the combustion flow field region corresponding to a single nozzle, including the equivalent width d and the equivalent height h; the combustion flow field region corresponding to a single nozzle is a fan-shaped arc segment, where the equivalent width d is the arc length of the central arc of the fan-shaped arc segment, and the equivalent height h is the radius of the fan-shaped arc segment: ; ; Then the aspect ratio of the combustion zone of a single nozzle is t = d / h.

[0006] Furthermore, the design process of the gas-liquid nozzle of the S30 is as follows: S31. Design the structure of the liquid centrifugal nozzle; The central flow channel of the liquid centrifugal nozzle adopts a circular structure to achieve swirling atomization, and the flow rate relationship is as follows: ; In the formula: The nozzle mass flow rate is expressed in kg / s. For flow coefficient; The nozzle inner diameter is in meters (m). This refers to the density of the liquid medium, in kg / m³. 3 ; The pressure drop across the nozzle is expressed in MPa. Flow coefficient The following can be obtained from the geometric characteristic value A: ; The geometric property value A is calculated by the following formula: ; In the formula: The number of tangential holes; The tangential orifice diameter is in mm; the nozzle wall thickness is... Larger than the tangential hole diameter More than 1.5 times that of the original, and must meet the structural strength design requirements; S32. Design a radial nozzle for the liquid center; To meet the requirement of uniformity of the spatial flow field under the condition that the aspect ratio t > 1, the outer periphery of the needle plug of the radial nozzle at the center of the liquid is changed from a circular structure to an elliptical structure. The specific design method of the corresponding elliptical liquid phase flow channel is as follows: The major semi-axis of the elliptical liquid flow channel With short half shaft The ratio is consistent with the aspect ratio t of the single-nozzle combustion zone; based on the nozzle inner diameter of the liquid centrifugal nozzle. and nozzle wall thickness The minor semi-axis of the elliptical liquid flow channel is obtained. Then the semi-major axis of the elliptical liquid flow channel Set the width of the elliptical liquid flow channel. and the outer wall thickness of the elliptical liquid phase flow channel The cross-sectional area of ​​the elliptical liquid flow channel was calculated. : ; Next, determine the number of liquid direct-flow injection orifices. and aperture Mass flow rate of liquid flowing through the direct current injection orifice The relationship between the flow area and the pressure before and after the flow is as follows: ; In the formula, The unit is the circulation area, in meters. 2 , ; For flow coefficient; The pressure of the liquid before it flows through the liquid direct injection orifice, in Pa; The pressure in the combustion chamber is the pressure of the liquid after it flows through the liquid direct injection orifice, measured in Pa. A uniformity control strategy is achieved by arranging each liquid direct-flow injection orifice with equal arc length along the outer surface of the nozzle. S33. Design of vapor phase injection annular seam structure; Based on the gas flow rate of a single nozzle The area of ​​the gas-phase injection annular joint is calculated using the following formula. : ; In the formula: The flow coefficient is set to 0.5. The area of ​​the gas-phase injection annular gap is expressed in meters. 2 ; This refers to the inlet pressure of the gas injection annular slit, i.e., the gas injection pressure, in Pa. Specific heat ratio of gases; It is the gas constant; The static temperature of the gas is measured in Kelvin (K); simultaneously, the inlet pressure of the gas-phase injection annular slit is... The following conditions must be met: ; Then, the area of ​​the annular gap is injected by vapor phase injection. The circumferential seam width is calculated using the formula for the circumference of an ellipse. : .

[0007] Furthermore, the design steps for the needle-type gas-liquid nozzle in S30 are S32 and S33 in sequence, wherein the short semi-axis of the liquid flow channel of the liquid center radial nozzle... If it is 1 / 5 to 1 / 3 of the combustion chamber radius, then the long half-shaft The vapor-phase injection annular seam has an elliptical structure, and the width of the vapor-phase injection annular seam is... Calculated according to formula (11); The design steps for a DC centrifugal gas-liquid nozzle are S31 and S33 in sequence. The central flow channel of the liquid centrifugal nozzle has a circular structure, and the outer periphery of the liquid centrifugal nozzle has an elliptical structure, based on the nozzle inner diameter. and nozzle wall thickness The minor semi-axis of the elliptical structure is obtained. Then the major semi-axis The vapor-phase injection annular seam has an elliptical structure, and the width of the vapor-phase injection annular seam is... Calculated according to formula (11); The design steps for the combined gas-liquid nozzle of the central centrifugal type and the peripheral needle plug type are S31, S32 and S33 in sequence.

[0008] The elliptical nozzle prototype for enhancing the flow field uniformity of the annular combustion chamber of the present invention is designed and manufactured using the design steps of a central centrifugal type and an outer peripheral needle-bolt type combined gas-liquid nozzle. The prototype includes a needle-bolt type elliptical nozzle fixed on a mounting seat of a nozzle mounting flange; several liquid centrifugal nozzles are arranged circumferentially on the inner wall of the needle-bolt type elliptical nozzle; several liquid direct injection holes are arranged on the outer surface of the needle-bolt type elliptical nozzle according to the principle of equal arc length; and a gas phase injection annular slit is provided circumferentially behind the liquid direct injection holes.

[0009] The elliptical nozzle design method and prototype for enhancing the flow field uniformity of the annular combustion chamber of the present invention achieves the improvement of the flow field uniformity of the annular combustion chamber through structural design, parameter optimization and other means, and has practical engineering value. Attached Figure Description

[0010] The accompanying drawings are for illustrative purposes only and are not intended to limit the scope of this disclosure. It is obvious that the drawings described below are merely some embodiments of this disclosure, and those skilled in the art can obtain other drawings based on these drawings without any inventive effort. Furthermore, the same reference numerals denote the same parts throughout the drawings.

[0011] Figure 1 This is a schematic diagram showing the dimensions of the combustion zone of a single nozzle in an annular combustion chamber. Figure 2 Key structural parameters of a liquid centrifugal nozzle (sectional view); Figure 3 Key structural parameters (sectional view) of the elliptical liquid phase flow channel for a needle-type gas-liquid nozzle. Figure 4 for Figure 3 AA cross-section view; Figure 5 Key structural parameters of the gas phase injection annular gap for needle-type gas-liquid nozzles (sectional view). Figure 6 Key structural parameters (section view) of the elliptical nozzle prototype designed to enhance the flow field uniformity in the annular combustion chamber. Figure 6 In the middle, 301. Liquid centrifugal nozzle; 302. Liquid direct current injection orifice; 303. Gas phase injection circumferential seam; 304. Nozzle mounting flange. Detailed Implementation

[0012] The present invention will now be described in detail with reference to the accompanying drawings and embodiments.

[0013] Example: The elliptical nozzle design method for enhancing the flow field uniformity of the annular combustion chamber in this example includes the following steps: S10. Confirm the size of the single-nozzle combustion zone; Based on the dimensions of the annular combustion chamber, design the number of nozzles, divide the single-nozzle combustion zone, and determine the aspect ratio t of the single-nozzle combustion zone, where t > 1; S20. Select nozzle type; The nozzle should be selected as a gas-liquid type nozzle. A gas-liquid type nozzle refers to a nozzle in which one component is gas and the other component is liquid. Specifically, it includes needle-type gas-liquid nozzles, direct-flow centrifugal gas-liquid nozzles, and combined gas-liquid nozzles of the center centrifugal type and the outer peripheral needle-type. The specific type of gas-liquid nozzle to be selected depends on the actual scenario. For situations where the working conditions are fixed or change only slightly, a needle-type gas-liquid nozzle or a direct-flow centrifugal gas-liquid nozzle can be selected alone. For situations where the working conditions need to change over a large range, a combination of a central centrifugal nozzle and a peripheral needle-type gas-liquid nozzle can be selected. S30. Design a gas-liquid type nozzle; The gas-liquid nozzle design includes a needle-type gas-liquid nozzle design, a direct-flow centrifugal gas-liquid nozzle design, and a combined gas-liquid nozzle design combining a central centrifugal nozzle and a peripheral needle-type nozzle. Specifically, the needle-type gas-liquid nozzle has a liquid-centered radial nozzle at its center, with multiple circumferentially distributed injection orifices at the front end of the needle, and a gas-phase injection annular slit on its outer periphery. The direct-flow centrifugal gas-liquid nozzle has a liquid-centrifugal nozzle at its center, with a gas-phase injection annular slit on its outer periphery. The combined gas-liquid nozzle combining a central centrifugal nozzle and a peripheral needle-type nozzle has a liquid-centrifugal nozzle in its inner center, a liquid-centered radial nozzle in its outer center, and a gas-phase injection annular slit on its outer periphery. During the design process, the needle plug was optimized from a circular structure to an elliptical structure; S40. Establish a uniformity control strategy; For the elliptical structure, the flow distribution scheme of the gas-liquid nozzle was adjusted through simulation calculation and experimental verification, the nozzle structural parameters were optimized, and a uniformity control strategy was established to achieve a uniform flow field in the annular combustion chamber and improve combustion efficiency.

[0014] Furthermore, the specific process of S10 is as follows: like Figure 1 As shown, based on the dimensions of the annular combustion chamber, the inner diameter d2 and outer diameter d1 of the annular combustion chamber are determined, and the number of nozzles n is determined. Calculate the basic dimensions of the combustion flow field region corresponding to a single nozzle, including the equivalent width d and the equivalent height h; the combustion flow field region corresponding to a single nozzle is a fan-shaped arc segment, where the equivalent width d is the arc length of the central arc of the fan-shaped arc segment, and the equivalent height h is the radius of the fan-shaped arc segment: ; ; Then the aspect ratio of the combustion zone of a single nozzle is t = d / h.

[0015] Due to structural space constraints and overall layout requirements, t is usually greater than 1. The flow field formed after combustion in a traditional circular nozzle will exhibit a relatively uniform temperature and component field in the central region, while the temperature and component fields near the two sides will deviate significantly.

[0016] Furthermore, the design process of the gas-liquid nozzle of the S30 is as follows: S31. Design the structure of the liquid centrifugal nozzle; like Figure 2 As shown, the central flow channel of the liquid centrifugal nozzle adopts a circular structure to achieve swirling atomization, and the flow rate relationship is: ; In the formula: The nozzle mass flow rate is expressed in kg / s. For flow coefficient; The nozzle inner diameter is in meters (m). Density of the liquid medium, in kg / m³ 3 ; The pressure drop across the nozzle is expressed in MPa. Flow coefficient The following can be obtained from the geometric characteristic value A: ; The geometric property value A is calculated by the following formula: ; In the formula: Number of tangential holes; The tangential orifice diameter is in mm; the nozzle wall thickness is... Larger than the tangential hole diameter More than 1.5 times that of the original, and must meet the structural strength design requirements; S32. Design a radial nozzle for the liquid center; To meet the requirement of uniformity of the spatial flow field under the condition that the aspect ratio t > 1, the outer periphery of the needle plug of the radial nozzle at the center of the liquid is changed from a circular structure to an elliptical structure. The specific design method of the corresponding elliptical liquid phase flow channel is as follows: like Figure 3 , Figure 4 As shown, the major semi-axis of the elliptical liquid flow channel With short half shaft The ratio is consistent with the aspect ratio t of the single-nozzle combustion zone; based on the nozzle inner diameter of the liquid centrifugal nozzle. and nozzle wall thickness The minor semi-axis of the elliptical liquid flow channel is obtained. Then the semi-major axis of the elliptical liquid flow channel Set the width of the elliptical liquid flow channel. and the outer wall thickness of the elliptical liquid phase flow channel The cross-sectional area of ​​the elliptical liquid flow channel was calculated. : ; Next, determine the number of liquid direct-flow injection orifices. and aperture Mass flow rate of liquid flowing through the direct current injection orifice The relationship between the flow area and the pressure before and after the flow is as follows: ; In the formula, The unit is the circulation area, in meters. 2 Because the liquid is throttled only at the liquid direct injection orifice, it is required that... ; For flow coefficient; The pressure of the liquid before it flows through the liquid direct injection orifice, in Pa; The pressure in the combustion chamber is the pressure of the liquid after it flows through the liquid direct injection orifice, measured in Pa. A uniformity control strategy is achieved by arranging each liquid direct-flow injection orifice with equal arc length along the outer surface of the nozzle. S33. Design of vapor phase injection annular seam structure; Based on the gas flow rate of a single nozzle The area of ​​the gas-phase injection annular joint is calculated using the following formula. : ; In the formula: This is the flow coefficient, typically taken as 0.5; The area of ​​the gas-phase injection annular gap is expressed in meters. 2 ; This refers to the inlet pressure of the gas injection annular slit, i.e., the gas injection pressure, in Pa. Specific heat ratio of gases; It is the gas constant; The static temperature of the gas is measured in Kelvin (K); simultaneously, the inlet pressure of the gas-phase injection annular slit is... The following conditions must be met: ; Then, the area of ​​the annular gap is injected by vapor phase injection. The circumference of an ellipse is calculated using the formula as follows: Figure 5 The shown circumferential seam width : .

[0017] Furthermore, the design steps for the needle-type gas-liquid nozzle in S30 are S32 and S33 in sequence, wherein the short semi-axis of the liquid flow channel of the liquid center radial nozzle... If it is 1 / 5 to 1 / 3 of the combustion chamber radius, then the long half-shaft The vapor-phase injection annular seam has an elliptical structure, and the width of the vapor-phase injection annular seam is... Calculated according to formula (11); The design steps for a DC centrifugal gas-liquid nozzle are S31 and S33 in sequence. The central flow channel of the liquid centrifugal nozzle has a circular structure, and the outer periphery of the liquid centrifugal nozzle has an elliptical structure, based on the nozzle inner diameter. and nozzle wall thickness The minor semi-axis of the elliptical structure is obtained. Then the major semi-axis The vapor-phase injection annular seam has an elliptical structure, and the width of the vapor-phase injection annular seam is... Calculated according to formula (11); The design steps for the combined gas-liquid nozzle of the central centrifugal type and the peripheral needle plug type are S31, S32 and S33 in sequence.

[0018] like Figure 5 , Figure 6 As shown, the elliptical nozzle prototype for enhancing the flow field uniformity of the annular combustion chamber in this embodiment is designed and manufactured using a design process combining a central centrifugal nozzle and an outer peripheral needle-type gas-liquid nozzle. The prototype includes a needle-type elliptical nozzle fixed on a mounting base of a nozzle mounting flange 304; a plurality of liquid centrifugal nozzles 301 are arranged circumferentially on the inner wall of the needle-type elliptical nozzle; a plurality of liquid direct injection holes 302 are arranged on the outer surface of the needle-type elliptical nozzle according to the principle of equal arc length; and a gas phase injection annular slit 303 is provided circumferentially behind the liquid direct injection holes 302.

[0019] Although the embodiments of the present invention have been disclosed above, they are not limited to the applications listed in the specification and embodiments. For those skilled in the art, all features disclosed in the present invention, or all steps in all methods or processes disclosed, except for mutually exclusive features and / or steps, can be combined in any way without departing from the principles of the present invention. The present invention is not limited to the specific details and illustrations shown and described herein.

Claims

1. A method for designing an elliptical nozzle to enhance the uniformity of the flow field in an annular combustion chamber, characterized in that, The elliptical nozzle design method includes the following steps: S10. Confirm the size of the single-nozzle combustion zone; Based on the dimensions of the annular combustion chamber, design the number of nozzles, divide the single-nozzle combustion zone, and determine the aspect ratio t of the single-nozzle combustion zone, where t > 1; S20. Select nozzle type; The nozzle should be selected as a gas-liquid type nozzle. A gas-liquid type nozzle refers to a nozzle in which one component is gas and the other component is liquid. Specifically, it includes needle-type gas-liquid nozzles, direct-flow centrifugal gas-liquid nozzles, and combined gas-liquid nozzles of the center centrifugal type and the outer peripheral needle-type. S30. Design a gas-liquid type nozzle; The gas-liquid nozzle design includes a needle-type gas-liquid nozzle design, a direct-flow centrifugal gas-liquid nozzle design, and a combined gas-liquid nozzle design combining a central centrifugal nozzle and a peripheral needle-type nozzle. Specifically, the needle-type gas-liquid nozzle has a liquid-centered radial nozzle at its center, with multiple circumferentially distributed injection orifices at the front end of the needle, and a gas-phase injection annular slit on its outer periphery. The direct-flow centrifugal gas-liquid nozzle has a liquid-centrifugal nozzle at its center, with a gas-phase injection annular slit on its outer periphery. The combined gas-liquid nozzle combining a central centrifugal nozzle and a peripheral needle-type nozzle has a liquid-centrifugal nozzle in its inner center, a liquid-centered radial nozzle in its outer center, and a gas-phase injection annular slit on its outer periphery. During the design process, the needle plug was optimized from a circular structure to an elliptical structure; S40. Establish a uniformity control strategy; For the elliptical structure, the flow distribution scheme of the gas-liquid nozzle was adjusted through simulation calculation and experimental verification, the nozzle structural parameters were optimized, and a uniformity control strategy was established to achieve a uniform flow field in the annular combustion chamber and improve combustion efficiency.

2. The elliptical nozzle design method for enhancing the flow field uniformity of the annular combustion chamber according to claim 1, characterized in that, The specific process of S10 is as follows: Based on the dimensions of the annular combustion chamber, determine the inner diameter d2 and outer diameter d1 of the annular combustion chamber, and then determine the number of nozzles n. Calculate the basic dimensions of the combustion flow field region corresponding to a single nozzle, including the equivalent width d and the equivalent height h; the combustion flow field region corresponding to a single nozzle is a fan-shaped arc segment, where the equivalent width d is the arc length of the central arc of the fan-shaped arc segment, and the equivalent height h is the radius of the fan-shaped arc segment: ； ； Then the aspect ratio of the combustion zone of a single nozzle is t = d / h.

3. The elliptical nozzle design method for enhancing the flow field uniformity of the annular combustion chamber according to claim 2, characterized in that, The design process of the gas-liquid nozzle of the S30 is as follows: S31. Design the structure of the liquid centrifugal nozzle; The central flow channel of the liquid centrifugal nozzle adopts a circular structure to achieve swirling atomization, and the flow rate relationship is as follows: ； In the formula: The nozzle mass flow rate is expressed in kg / s. For flow coefficient; The nozzle inner diameter is in meters (m). Density of the liquid medium, in kg / m³ 3 ; The pressure drop across the nozzle is expressed in MPa. Flow coefficient The following can be obtained from the geometric characteristic value A: ； The geometric property value A is calculated by the following formula: ； In the formula: Number of tangential holes; The tangential orifice diameter is in mm; the nozzle wall thickness is... Larger than the tangential hole diameter More than 1.5 times that of the original, and must meet the structural strength design requirements; S32. Design a radial nozzle for the liquid center; To meet the requirement of uniformity of the spatial flow field under the condition that the aspect ratio t > 1, the outer periphery of the needle plug of the radial nozzle at the center of the liquid is changed from a circular structure to an elliptical structure. The specific design method of the corresponding elliptical liquid phase flow channel is as follows: The major semi-axis of the elliptical liquid flow channel With short half shaft The ratio is consistent with the aspect ratio t of the single-nozzle combustion zone; based on the nozzle inner diameter of the liquid centrifugal nozzle. and nozzle wall thickness The minor semi-axis of the elliptical liquid flow channel is obtained. Then the semi-major axis of the elliptical liquid flow channel ; Set the width of the elliptical liquid phase flow channel and the outer wall thickness of the elliptical liquid phase flow channel The cross-sectional area of ​​the elliptical liquid flow channel was calculated. : ； Next, determine the number of liquid direct-flow injection orifices. and aperture Mass flow rate of liquid flowing through the direct current injection orifice The relationship between the flow area and the pressure before and after the flow is as follows: ； In the formula, The unit is the circulation area, in meters (m). 2 , ; For flow coefficient; The pressure of the liquid before it flows through the liquid direct injection orifice, in Pa; The pressure in the combustion chamber is the pressure of the liquid after it flows through the liquid direct injection orifice, measured in Pa. A uniformity control strategy is achieved by arranging each liquid direct-flow injection orifice with equal arc length along the outer surface of the nozzle. S33. Design of vapor phase injection annular seam structure; Based on the gas flow rate of a single nozzle The area of ​​the gas-phase injection annular joint is calculated using the following formula. : ； In the formula: The flow coefficient is set to 0.

5. The area of ​​the gas-phase injection annular gap is expressed in meters. 2 ; This refers to the inlet pressure of the gas injection annular slit, i.e., the gas injection pressure, in Pa. Specific heat ratio of gases; It is the gas constant; The static temperature of the gas is measured in Kelvin (K); simultaneously, the inlet pressure of the gas-phase injection annular slit is... The following conditions must be met: ； Then, the area of ​​the annular gap is injected by vapor phase injection. The circumferential seam width is calculated using the formula for the circumference of an ellipse. : 。 4. The elliptical nozzle design method for enhancing the flow field uniformity of the annular combustion chamber according to claim 3, characterized in that, The design steps for the needle-type gas-liquid nozzle in S30 are S32 and S33, wherein the short half-axis of the liquid flow channel of the liquid center radial nozzle is... If it is 1 / 5 to 1 / 3 of the combustion chamber radius, then the long half-shaft The vapor-phase injection annular seam has an elliptical structure, and the width of the vapor-phase injection annular seam is... Calculated according to formula (11); The design steps for a DC centrifugal gas-liquid nozzle are S31 and S33 in sequence. The central flow channel of the liquid centrifugal nozzle has a circular structure, and the outer periphery of the liquid centrifugal nozzle has an elliptical structure, based on the nozzle inner diameter. and nozzle wall thickness The minor semi-axis of the elliptical structure is obtained. Then the major semi-axis The vapor-phase injection annular seam has an elliptical structure, and the width of the vapor-phase injection annular seam is... Calculated according to formula (11); The design steps for the combined gas-liquid nozzle of the central centrifugal type and the peripheral needle plug type are S31, S32 and S33 in sequence.

5. An elliptical nozzle prototype for enhancing the uniformity of the flow field in an annular combustion chamber, designed and manufactured according to the design steps of the central centrifugal and peripheral needle-bolt combined gas-liquid nozzle in the elliptical nozzle design method for enhancing the uniformity of the flow field in an annular combustion chamber as described in claim 4, characterized in that... The sample includes a needle-type elliptical nozzle fixed on a mounting base of a nozzle mounting flange (304); a number of liquid centrifugal nozzles (301) are arranged circumferentially on the inner wall of the needle-type elliptical nozzle; a number of liquid direct injection holes (302) are arranged on the outer surface of the needle-type elliptical nozzle according to the principle of equal arc length; a gas phase injection annular slit (303) is provided circumferentially behind the liquid direct injection holes (302).

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