Sectional type annular circulation cooling protection exhaust and expansion structure and control method thereof

Abstract

The invention relates to the field of aero-engine air environment simulation test equipment, and discloses a sectional type annular circulation cooling protection exhaust expansion structure and a control method thereof.By adopting sectional type water flow organization, a cooling channel of an exhaust diffuser is adjusted from a traditional axial flow channel to a circumferential flow channel in which water flow flows in the circumferential direction of a cylinder wall, so that the cooling effect of the exhaust diffuser is improved; a cooling medium flows section by section in the annular direction, the temperature of the wall of an inner cylinder of the exhaust diffuser is greatly reduced, and therefore the service life of the exhaust diffuser is prolonged. According to the invention, the cooling water introduction amount of each cooling medium channel is strictly controlled, and the flow design of the cooling water considers the influence of parameters such as the flow and the temperature of the fuel gas and the temperature rise required by the cooling water, so that the accurate control of the temperature of the fuel gas side of the exhaust diffuser is ensured; and various functions of the exhaust diffuser are really realized.

Description

Technical Field

[0001] The invention relates to the field of aerial environment simulation test equipment for aircraft engines, and discloses a segmented annular flow cooling protection exhaust expansion structure and a control method thereof. Background Art

[0002] The main function of the exhaust diffuser is to collect the high-temperature and high-speed combustion gas exhausted by the engine and convert the kinetic energy of the high-speed airflow into pressure energy, which is equivalent to the first "boosting" of the two streams of gas exhausted by the engine and the air entering the diffuser to reduce the burden on the exhaust fan or expand the boundary of the direct exhaust to the atmosphere, while providing a relatively uniform temperature field for the cooler inlet.

[0003] When the engine is running, the exhaust temperature is as high as 1850℃, and the exhaust diffuser barrel must be cooled, often by means of an axial flow cooling jacket. As the size of the exhaust diffuser increases, the thermal radiation of the gas increases, and the water flow rate of the traditional axial water flow organization is low and cannot be adjusted, resulting in high wall temperature that cannot meet the high-temperature thermal protection requirements. On the one hand, the gas in the exhaust diffuser is in a high-temperature negative pressure condition for a long time, and the inner barrel must meet the requirements of external pressure instability (high stiffness requirements); on the other hand, due to the large temperature difference of the jacket wall, the stiffness must be small to avoid structural failure; the two are contradictory. Summary of the invention

[0004] The object of the present invention is to provide a segmented annular flow cooling protection exhaust diffuser structure and a control method thereof, which can significantly reduce the inner cylinder wall temperature of the exhaust diffuser and improve the service life of the exhaust diffuser on the basis of ensuring accurate control of the gas side temperature of the exhaust diffuser.

[0005] In order to achieve the above technical effects, the technical solution adopted by the present invention is: A segmented annular circulation cooling protection and expansion structure comprises an inner cylinder and an outer cylinder, wherein the outer cylinder is sleeved on the outer circumference of the inner cylinder; a plurality of water-blocking ring plates are arranged between the inner cylinder and the outer cylinder along the axial direction of the inner cylinder, the outer edge of each water-blocking ring plate is sealedly connected to the inner wall of the outer cylinder, the inner edge of each water-blocking ring plate is sealedly connected to the outer wall of the inner cylinder, and an independent cooling medium channel is formed between two adjacent water-blocking ring plates; two vertical partitions are arranged in each cooling medium channel, and the two vertical partitions are used to divide the corresponding cooling medium channel into two symmetrical and independent semi-annular channels; one end of each semi-annular channel is connected to a water inlet pipe, and the other end of each semi-annular channel is connected to a water outlet pipe.

[0006] Furthermore, a notch section is provided on the outer cylinder body, and a cylindrical flexible connecting section is connected to the outer wall of the outer cylinder body. The notch section is located inside the flexible connecting section, and a connecting ring plate is annularly fixed to the outer wall of the inner cylinder body corresponding to the notch section. The connecting ring plate passes through the notch section position and is fixed on the flexible connecting section.

[0007] Furthermore, a sealing ring matching with the notch section is arranged on the connecting ring plate.

[0008] Furthermore, the water inlet pipe or the water outlet pipe is connected to the outer cylinder through a flexible pipe.

[0009] Furthermore, each of the water inlet pipes is provided with a flow regulating valve.

[0010] In order to achieve the above technical effects, the present invention also provides a control method for a segmented annular flow cooling protection exhaust expansion structure, comprising: Measure or simulate the gas flow rate of the exhaust diffuser in the working state, and the average temperature of the gas at the inner cylinder cavity position corresponding to each cooling medium channel; According to the gas flow rate, the average temperature, and the cooling water requirement control temperature rise required by the design, the cooling water flow analysis value of the corresponding cooling medium channel is obtained by analysis; According to the cooling water flow analysis value, cooling water is supplied to the corresponding cooling medium channel, and the cooling water flow of each semi-ring channel in the same cooling medium channel is equal.

[0011] Furthermore, the flow rate of cooling water in each cooling medium channel is based on The analysis obtained is the total mass flow rate of cooling water in the cooling medium channel, is the heat transfer efficiency, The value range is 0.05~0.25. is the gas mass flow rate in the inner cylinder cavity, is the specific heat capacity of the gas, is the average gas temperature at the corresponding position of each cooling medium channel, is the specific heat capacity of water, To control the temperature rise in accordance with the cooling water requirements of the corresponding cooling medium channel.

[0012] Furthermore, along the airflow direction, the required controlled temperature rise of the cooling water in the cooling medium channel decreases in a gradient.

[0013] Compared with the prior art, the present invention has the following beneficial effects: 1. The present invention adopts a segmented water flow organization to adjust the cooling channel of the exhaust diffuser from a traditional axial flow channel to a circumferential flow channel where water flows circumferentially along the cylinder wall, so that the cooling medium flows in sections along the annular direction, greatly reducing the wall temperature of the cylinder inside the exhaust diffuser, thereby improving the service life of the exhaust diffuser.

[0014] 2. In the present invention, the amount of cooling water introduced into each cooling medium channel is strictly controlled, and the flow design of the cooling water takes into account the influence of parameters such as the flow and temperature of the gas and the temperature rise required to be controlled by the cooling water, thereby ensuring precise control of the temperature on the gas side of the exhaust diffuser, so that the various functions of the exhaust diffuser can be truly realized. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 It is a schematic diagram of the segmented annular flow cooling protection exhaust expansion structure in the embodiment; Figure 2 It is a cross-sectional schematic diagram of a segmented annular flow cooling protection exhaust expansion structure in an embodiment; Figure 3 This is a schematic diagram of the structure of the flexible connecting section in the embodiment; Among them, 1. inner cylinder; 2. outer cylinder; 3. water-blocking ring plate; 4. cooling medium channel; 401. semi-ring channel; 5. vertical partition; 6. water inlet pipe; 7. water outlet pipe; 8. notch section; 9. flexible connection section; 10. connecting ring plate; 11. sealing ring; 12. flexible pipe fittings; 13. flow regulating valve. DETAILED DESCRIPTION

[0016] The present invention is further described in detail below in conjunction with the embodiments and drawings. However, it should not be understood that the scope of the above subject matter of the present invention is limited to the following embodiments, and all technologies realized based on the content of the present invention belong to the scope of the present invention.

[0017] Example See also Figure 1-Figure 3 A segmented annular circulation cooling protection and expansion structure comprises an inner cylinder 1 and an outer cylinder 2, wherein the outer cylinder 2 is sleeved on the outer periphery of the inner cylinder 1; a plurality of water-blocking ring plates 3 are arranged between the inner cylinder 1 and the outer cylinder 2 along the axial direction of the inner cylinder 1, the outer edge of each of the water-blocking ring plates 3 is sealedly connected to the inner wall of the outer cylinder 2, the inner edge of each of the water-blocking ring plates 3 is sealedly connected to the outer wall of the inner cylinder 1, and an independent cooling medium channel 4 is formed between two adjacent water-blocking ring plates 3; two vertical partitions 5 are arranged in each cooling medium channel 4, and the two vertical partitions 5 are used to divide the corresponding cooling medium channel 4 into two symmetrical and independent semi-annular channels 401; one end of each of the semi-annular channels 401 is connected to a water inlet pipe 6, and the other end of each of the semi-annular channels 401 is connected to a water outlet pipe 7.

[0018] In this embodiment, by adopting a segmented water flow organization, the cooling channel of the exhaust diffuser is adjusted from a traditional axial flow channel to a circumferential flow channel in which water flows circumferentially along the cylinder wall, so that the cooling medium flows in sections along the annular direction, which greatly reduces the wall temperature of the cylinder 1 inside the exhaust diffuser, thereby improving the service life of the exhaust diffuser.

[0019] In this embodiment, the outer cylinder 2 is further provided with a notch section 8, and the outer wall of the outer cylinder 2 is further connected with a cylindrical flexible connection section 9, the notch section 8 is located inside the flexible connection section 9, and a connecting ring plate 10 is annularly fixed to the outer wall of the inner cylinder 1 corresponding to the notch section 8, and the connecting ring plate 10 passes through the notch section 8 and is fixed to the flexible connection section 9. The connecting ring plate 10 is used in conjunction with the flexible connection section 9, and can also coordinate the thermal deformation between the inner cylinder 1 and the outer cylinder 2 under external pressure, reduce the overall stress of the exhaust diffuser, thereby further improving the service life and ensuring the safety of the test.

[0020] In this embodiment, a sealing ring 11 is provided on the connecting ring plate 10, which cooperates with the notch section 8. While meeting the thermal deformation of the inner cylinder 1, it can play a sealing role to prevent cooling water from entering the gap between the flexible connecting section 9 and the outer cylinder 2 from the notch. While ensuring the cooling effect, it can ensure the normal expansion and contraction of the flexible connecting section 9, avoiding the problem that cooling water can easily penetrate into the gap between the flexible connecting section 9 and the outer cylinder 2, causing the flexible connecting section 9 to be unable to absorb the thermal deformation of the inner cylinder 1.

[0021] The water inlet pipe 6 or the water outlet pipe 7 in this embodiment is connected to the outer cylinder 2 through the flexible pipe 12, which can absorb the axial deformation of the outer cylinder 2, thereby avoiding the problem that the fixed water inlet pipe 6 or the water outlet pipe 7 will affect the axial thermal deformation of the outer cylinder 2 and cause excessive axial stress of the outer cylinder 2.

[0022] In this embodiment, a flow regulating valve 13 is provided on each of the water inlet pipes 6 , so as to realize accurate control of the cooling water flow in each semi-annular channel 401 .

[0023] Based on the same inventive concept, this embodiment provides a control method for a segmented annular flow cooling protection exhaust expansion structure, including: Step 1: Measure or simulate the gas flow rate of the exhaust diffuser in the working state, and the average temperature of the gas at the inner cavity position of the inner cylinder 1 corresponding to each cooling medium channel 4; Step 2: According to the gas flow rate, the average temperature, and the cooling water requirement of the design, the temperature rise is controlled, and the cooling water flow analysis value corresponding to the cooling medium channel 4 is analyzed and obtained; Step three: supply cooling water into the corresponding cooling medium channel 4 according to the cooling water flow analysis value, and the cooling water flow of each semi-annular channel 401 in the same cooling medium channel 4 is equal.

[0024] In this embodiment, the amount of cooling water introduced into each cooling medium channel 4 is strictly controlled, and the flow rate design of the cooling water takes into account the influence of parameters such as the flow rate and temperature of the gas and the temperature rise required to be controlled by the cooling water, thereby ensuring precise control of the temperature on the gas side of the exhaust diffuser, so that the various functions of the exhaust diffuser can be truly realized.

[0025] In this embodiment, the flow rate of cooling water in each cooling medium channel 4 is based on The analysis obtained is the total mass flow rate of cooling water in the cooling medium channel 4, is the heat transfer efficiency, The value range is 0.05~0.25. is the gas mass flow rate in the inner cavity of the inner cylinder 1, is the specific heat capacity of the gas, is the average gas temperature at the corresponding position of each cooling medium channel 4, is the specific heat capacity of water, To control the temperature rise in accordance with the requirements of the cooling water in the cooling medium channel 4.

[0026] In this embodiment, the characteristics of the change in gas temperature along the flow direction of the airflow are taken into account. When the required control temperature rise parameters of the cooling water in each cooling medium channel 4 are performed, the required control temperature rise of the cooling water in the cooling medium channel 4 decreases gradually along the flow direction of the airflow, thereby meeting the control requirements for the temperature on the gas side of the exhaust diffuser.

[0027] The above are only preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A segmented annular flow cooling protection exhaust expansion structure, characterized in that: It comprises an inner cylinder and an outer cylinder, wherein the outer cylinder is sleeved on the outer circumference of the inner cylinder; a plurality of water-blocking ring plates are arranged between the inner cylinder and the outer cylinder at intervals along the axial direction of the inner cylinder, the outer edge of each of the water-blocking ring plates is sealedly connected to the inner wall of the outer cylinder, the inner edge of each of the water-blocking ring plates is sealedly connected to the outer wall of the inner cylinder, and an independent cooling medium channel is formed between two adjacent water-blocking ring plates; two vertical partitions are arranged in each cooling medium channel, and the two vertical partitions are used to divide the corresponding cooling medium channel into two symmetrical and independent semi-ring channels; one end of each of the semi-ring channels is connected to a water inlet pipe, and the other end of each of the semi-ring channels is connected to a water outlet pipe.

2. The segmented annular flow cooling protection exhaust expansion structure according to claim 1 is characterized in that: The outer cylinder body is also provided with a notch section, and the outer wall of the outer cylinder is also connected with a cylindrical flexible connecting section, the notch section is located inside the flexible connecting section, and a connecting ring plate is annularly fixed at the outer wall position of the inner cylinder corresponding to the notch section, and the connecting ring plate passes through the notch section position and is fixed on the flexible connecting section.

3. The segmented annular flow cooling protection exhaust expansion structure according to claim 1 is characterized in that: The connecting ring plate is provided with a sealing ring matched with the notch section.

4. The segmented annular flow cooling protection exhaust expansion structure according to claim 1 is characterized in that: The water inlet pipe or the water outlet pipe is communicated with the outer cylinder through a flexible pipe.

5. The segmented annular flow cooling protection exhaust expansion structure according to claim 1 is characterized in that: Each of the water inlet pipes is provided with a flow regulating valve.

6. A control method for a segmented annular flow cooling protection exhaust expansion structure, characterized in that: include: Measure or simulate the gas flow rate of the exhaust diffuser in the working state, and the average temperature of the gas at the inner cylinder cavity position corresponding to each cooling medium channel; According to the gas flow rate, the average temperature, and the cooling water requirement control temperature rise required by the design, the cooling water flow analysis value of the corresponding cooling medium channel is obtained by analysis; According to the cooling water flow analysis value, cooling water is supplied to the corresponding cooling medium channel, and the cooling water flow of each semi-ring channel in the same cooling medium channel is equal.

7. The control method of the segmented annular flow cooling protection exhaust expansion structure according to claim 6 is characterized in that: The flow rate of cooling water in each cooling medium channel is based on The analysis obtained is the total mass flow rate of cooling water in the cooling medium channel, is the heat transfer efficiency, The value range is 0.05~0.

25. is the gas mass flow rate in the inner cylinder cavity, is the specific heat capacity of the gas, is the average gas temperature at the corresponding position of each cooling medium channel, is the specific heat capacity of water, To control the temperature rise in accordance with the cooling water requirements of the corresponding cooling medium channel.

8. The control method of the segmented annular flow cooling protection exhaust expansion structure according to claim 7 is characterized in that: Along the airflow direction, the required controlled temperature rise of the cooling water in the cooling medium channel decreases gradually.

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