High-temperature-resistant impedance combined type noise reduction system for marine gas turbine

Abstract

The invention relates to the technical field of steam turbine silencers, in particular to a high-temperature-resistant impedance combined type silencing system for a marine gas turbine, which comprises an impedance combined type silencer arranged at a turbine outlet of the marine gas turbine, and the impedance combined type silencer comprises a resistant silencing section close to the turbine outlet. The resistance silencing section is located at the downstream of the resistance silencing section, the resistance silencing section comprises a shell, a plurality of expansion chambers are arranged in the shell, the expansion chambers are connected with a turbine of the marine gas turbine through inlet pipes, the expansion chambers are connected with the resistance silencing section through outlet pipes, and a refrigerant outlet and a refrigerant inlet are formed in the shell.

Description

Technical Field

[0001] This invention relates to the field of turbine silencer technology, specifically a high-temperature resistant impedance composite silencer system for marine gas turbines. Background Technology

[0002] In marine propulsion systems, marine gas turbines, with their high power density and fast start-up response, have become the core power plant for modern ocean-going vessels and special-purpose ships. However, the high-temperature exhaust gas discharged from the turbine outlet during gas turbine operation can reach temperatures of 600-800℃ and is accompanied by strong noise of 110-130dB. This can cause thermal radiation damage to ship deck equipment and impair acoustic stealth performance during navigation. Therefore, a silencer system has become an essential component of gas turbine power units. Impedance composite silencers, which combine the structural interference noise reduction of resistive silencers with the sound absorption noise reduction of resistive silencers, have become the preferred solution for marine applications. However, in high-temperature environments, traditional designs always face the challenge of balancing high-temperature resistance and noise reduction effect. The sound-absorbing materials of resistive silencers are prone to pyrolysis and carbonization at high temperatures, while the metal structure of resistive silencers is prone to deformation due to thermal stress concentration, leading to a shift in the noise reduction frequency. Both factors contribute to the short-term failure of the silencer system.

[0003] Improving the high-temperature resistance of impedance composite silencers hinges on addressing two major issues: "high-temperature thermal erosion" and "structural thermal stability." Existing technologies often have significant limitations. Some solutions replace the sound-absorbing lining with a single high-temperature resistant material, such as ceramic fiber. However, these materials have low sound absorption coefficients, leading to a reduction in silencing performance of over 30%. Another solution enhances heat resistance by thickening the shell wall of the silencing section, but this increases the equipment weight by 40%, contradicting the "lightweight" design requirements of ships. More critically, traditional silencers lack a targeted active cooling mechanism, relying solely on natural heat dissipation. When gas turbine load fluctuations cause a sudden rise in exhaust gas temperature, heat rapidly accumulates in core structures such as the expansion chamber, leading to seal failure at the inlet and outlet pipe interfaces and subsequent high-temperature exhaust gas leakage. This "passive bearing" design approach leaves the silencer in a vicious cycle of "weak silencing with high-temperature resistance, and poor heat resistance with strong silencing," failing to meet the complex and variable operating conditions of marine gas turbines.

[0004] The constraints imposed by the marine navigation environment on equipment size and adaptability to various operating conditions further exacerbate the urgency of technological breakthroughs. Shipborne equipment must strictly adhere to the principle of "minimal space utilization." Traditional silencers, in order to balance heat resistance and noise reduction, often increase their overall size, resulting in a 50% increase in installation space and severely impacting the layout flexibility of the ship's powerhouse. Simultaneously, the exhaust gas temperature of a gas turbine can fluctuate by over 300°C under different operating conditions such as start-up, acceleration, and cruising. Fixed-parameter cooling systems struggle to match dynamic temperature changes, either resulting in insufficient cooling at high temperatures leading to component damage or overcooling at low temperatures causing energy waste. Therefore, developing a noise reduction system that can actively adapt to temperature changes and achieve a balance between "high temperature resistance, strong noise reduction, and small size" within a compact structure has become crucial for overcoming the performance bottlenecks of marine gas turbine power systems. Summary of the Invention

[0005] To achieve the above objectives, the present invention provides the following technical solution: A high-temperature resistant impedance composite silencing system for marine gas turbines includes an impedance composite silencer disposed at the turbine outlet of the marine gas turbine. The impedance composite silencer includes a reactive silencing section near the turbine outlet and a resistive silencing section downstream of the reactive silencing section. The reactive silencing section includes a shell containing multiple expansion chambers. The multiple expansion chambers are connected to the turbine of the marine gas turbine via inlet pipes. The multiple expansion chambers are connected to the resistive silencing section via outlet pipes. The shell is provided with a refrigerant outlet and a refrigerant inlet. Refrigerant fluid enters the shell from the refrigerant inlet, passes through the multiple expansion chambers and carries away the heat from the expansion chambers, and then exits from the refrigerant outlet. The resistive silencing section is provided with metal fiber-lined sound-absorbing louvers.

[0006] Furthermore, the resistant silencing section includes an expansion chamber and a cooling cavity located between the shell and the expansion chamber. The silencing performance is maintained while ensuring thermal management by controlling the refrigerant fluid velocity within the cooling cavity.

[0007] Furthermore, a first sensor assembly is installed at the inlet pipe of the resistive noise reduction section, and the first sensor assembly monitors the exhaust gas velocity. and exhaust gas temperature A second sensor assembly is installed at the refrigerant inlet, and the second sensor assembly collects the refrigerant inlet temperature. and the current refrigerant flow rate Based on the heat transfer coefficient of the exhaust gas side Assess the current heat load Q and predict the expansion chamber wall temperature. To determine whether the flow rate needs adjustment; the controller calculates the required refrigerant flow rate based on the heat balance equation. The controller generates control commands and determines the flow rate adjustment amount. .

[0008] Furthermore, the current heat load Q is the heat that the cooling system needs to remove. Where Q is the heat to be transferred. The exhaust gas side convective heat transfer coefficient is... For heat transfer area, To increase the temperature of the expansion chamber wall.

[0009] Furthermore, the diameter D of the expansion chamber of the resistive silencing section, the diameter d of the inlet pipe, and the heat exchange area... The following constraint must be satisfied; the expansion chamber at frequency The propagation loss under the following conditions is satisfied. ,in, Indicates the expansion ratio. The wave number is represented by c, and the speed of sound in the exhaust gas is c; the refrigerant fluid needs to absorb at least the heat load. Calories, ,in, The convective heat transfer coefficient on the cold side is... For refrigerant mass flow rate, For the specific heat capacity of the refrigerant, For gas temperature, This refers to the refrigerant inlet temperature.

[0010] Furthermore, the plurality of expansion chambers are a first expansion chamber, a second expansion chamber, and a third expansion chamber arranged in parallel; the inlets of the first expansion chamber, the second expansion chamber, and the third expansion chamber are all connected to the inlet pipe, and the outlets of the first expansion chamber, the second expansion chamber, and the third expansion chamber are all connected to the outlet pipe; the refrigerant fluid passes through the first expansion chamber, the second expansion chamber, and the third expansion chamber.

[0011] Furthermore, the airflow in the parallel-connected first expansion chamber, second expansion chamber, and third expansion chamber satisfies the following mass conservation constraints: ,in, For gas density, Let be the airflow velocity in the i-th expansion chamber. Let i be the cross-sectional area of ​​the i-th expansion chamber. The airflow velocity in the main pipe, This is the cross-sectional area of ​​the main pipe.

[0012] Furthermore, the overall transfer loss of the multiple expansion chambers must meet the following requirements: Wherein, the transmission loss of the i-th expansion chamber is, ,in, This represents the expansion ratio of the i-th expansion chamber. Let be the diameter of the i-th expansion chamber. Let be the diameter of the connecting pipe of the i-th expansion chamber. Indicates wave number.

[0013] Furthermore, the refrigerant fluid needs to absorb at least the heat load. Calories, The overall heat transfer equation of the cooling cavity within the shell, ,in, For refrigerant mass flow rate, For the specific heat capacity of the refrigerant, For gas temperature, This refers to the refrigerant inlet temperature. This refers to the refrigerant outlet temperature. The total heat transfer area is represented by U, and the overall heat transfer coefficient U is obtained through... Obtain, among which, The heat transfer coefficient is the refrigerant side heat transfer coefficient. , For the thermal conductivity of the refrigerant, The hydraulic diameter, For the refrigerant side Nusselt number, This is the heat transfer coefficient on the exhaust side.

[0014] Furthermore, the resistive silencing section is provided with sound-absorbing louvers made of metal fibers, and the sound-absorbing louvers form a channel structure to achieve resistive silencing.

[0015] The beneficial effects of this invention are significant. Compared to traditional marine gas turbine mufflers, this invention has a significant advantage in improving the high-temperature resistance of impedance composite mufflers. Through a cooling system, dynamic control strategy, and structural optimization, this invention significantly improves the high-temperature resistance of the muffler system. Traditional mufflers often rely on passive thermal protection or simple insulation materials, which are insufficient to withstand the high-temperature impact of gas turbine exhaust, leading to material aging, decreased muffler performance, and even structural failure. In contrast, this invention integrates an active cooling mechanism, setting a cooling chamber between the shell of the resistive muffler section and multiple parallel expansion chambers. The refrigerant fluid enters from the refrigerant inlet, flows over the surface of the expansion chamber, and exits from the refrigerant outlet, carrying away heat. This ensures that the expansion chamber wall temperature remains below the material's temperature resistance limit, thereby preventing thermal deformation or degradation. Simultaneously, the system adjusts the refrigerant mass flow rate in real time according to the exhaust gas temperature, achieving dynamic thermal management through control equations. This feedforward-feedback control not only improves cooling efficiency but also prevents energy waste caused by over-cooling, ensuring stable muffler performance. In addition, the parallel expansion chamber layout enhances the uniformity of heat distribution and reduces local hot spots. Combined with the resistive silencing section with metal fiber lining, the material maintains its acoustic properties at high temperatures, further improving overall durability. While ensuring sound absorption and high temperature resistance, the optimization of the cooling system reduces the size of the resistive silencing section and the thickness of the cooling cavity, achieving miniaturization and solving the problem of balancing performance in a compact space in traditional designs. Attached Figure Description

[0016] Figure 1 This is a schematic diagram of the high-temperature resistant impedance composite silencing system for marine gas turbines according to the present invention. Figure 2 This is a schematic diagram of the impedance composite silencer of the present invention; Figure 3 This is a control flowchart of the reactive silencing section in the impedance composite silencer of the present invention; In the figure: impedance composite silencer 100, marine gas turbine 200, reactive silencer section 10, resistive silencer section 20, inlet pipe 11, expansion chamber 12, outlet pipe 13, refrigerant outlet 14, refrigerant inlet 15, shell 16. Detailed Implementation The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0017] The present invention will now be described in detail with reference to the accompanying drawings. The present invention provides a high-temperature resistant impedance composite silencing system for marine gas turbines, comprising an impedance composite silencer 100 disposed at the turbine outlet of a marine gas turbine 200. The impedance composite silencer 100 includes a reactive silencing section 10 near the turbine outlet and a resistive silencing section 20 downstream of the reactive silencing section 10. The reactive silencing section 10 includes a housing 16, in which a plurality of expansion chambers 12 are disposed. Each expansion chamber 12 is connected to the turbine of the marine gas turbine 200 via an inlet pipe 11; the multiple expansion chambers 12 are connected to the resistive silencing section 20 via an outlet pipe 13; the housing 16 is provided with a refrigerant outlet 14 and a refrigerant inlet 15, the refrigerant fluid enters the housing 16 from the refrigerant inlet 15, the refrigerant fluid passes through the multiple expansion chambers 12 and carries away the heat of the expansion chambers 12 before being discharged from the refrigerant outlet 14; the resistive silencing section 20 is provided with sound-absorbing louvers lined with metal fibers.

[0018] In the high-temperature impedance composite silencing system of the present invention, the resistive silencing section 10 in the high-temperature zone prioritizes high-temperature resistance and reliability, mainly relying on resistive silencing and a cooling cavity provided in the shell 16 to cool the expansion chamber 12; in the resistive silencing section 20 in the medium and low temperature zone, the advantages of impedance composite are emphasized, and high-performance high-temperature sound-absorbing materials are used to achieve broadband silencing. Specifically, the resistive silencing section 20 can be equipped with silencing louvers or channel structures made of high-temperature resistant materials such as metal fibers and ceramic fibers.

[0019] Example 1 Marine gas turbines generate high-intensity noise and high-temperature exhaust gas during operation, requiring a silencing system that simultaneously possesses good noise reduction performance and high-temperature resistance. The resistive silencing section 10 of the impedance composite silencing system of the present invention includes an expansion chamber 12 and a cooling cavity located between the shell 16 and the expansion chamber 12. By controlling the refrigerant fluid velocity within the cooling cavity, effective thermal management is ensured while maintaining silencing performance.

[0020] Specifically, a first sensor assembly is installed at the inlet pipe 11 of the resistive noise reduction section 10, and the first sensor assembly monitors the exhaust gas velocity. and exhaust gas temperature A second sensor assembly is installed at the refrigerant inlet 15, and the second sensor assembly collects the refrigerant inlet temperature. and the current refrigerant flow rate Based on the heat transfer coefficient of the exhaust gas side Assess the current heat load Q and predict the expansion chamber wall temperature. To determine whether the flow rate needs adjustment; the controller calculates the required refrigerant flow rate based on the heat balance equation. The controller generates control commands and determines the flow rate adjustment amount. .

[0021] The current heat load Q is the heat that the cooling system needs to remove, which is determined by the exhaust gas condition. Where Q is the amount of heat to be transferred. The exhaust gas side convective heat transfer coefficient is... For heat transfer area, To increase the temperature of the expansion chamber wall.

[0022] The exhaust gas side heat transfer coefficient ,in, For the thermal conductivity of the exhaust gas, The exhaust-side Nusselt number, where , The exhaust Reynolds number, This is the Prandtl number for exhaust gases.

[0023] The heat that the refrigerant needs to remove on the cooling side. And at the same time, it needs to satisfy ,in, For refrigerant mass flow rate, For the specific heat capacity of the refrigerant, This refers to the refrigerant inlet temperature. This refers to the refrigerant outlet temperature. The average temperature of the refrigerant. The heat transfer coefficient on the refrigerant side is denoted as .

[0024] The relationship between the refrigerant mass flow rate and flow velocity satisfies ,in, For refrigerant density, For refrigerant flow rate, This represents the cross-sectional area of ​​the cooling channel.

[0025] The heat transfer coefficient on the refrigerant side ,in, For the thermal conductivity of the refrigerant, The hydraulic diameter, For the refrigerant side Nusselt number, For refrigerant Reynolds number, For refrigerant, Trump number.

[0026] The governing equation for the required refrigerant flow rate is: The wall temperature Determined by the following equation, .

[0027] Example 2 Large marine gas turbine silencers not only take up space but also significantly raise the ship's center of gravity, impairing navigation stability and safety. Miniaturizing the silencer through compact design can optimize the ship's space utilization, weight distribution, and fuel efficiency while ensuring noise reduction and high-temperature resistance.

[0028] The impedance composite silencer 100 achieves miniaturization while meeting the necessary noise reduction and high-temperature resistance requirements. Specifically, the difference in sound power level at the silencer inlet is the transmission loss and a key indicator for evaluating the silencer's noise reduction capability. The expansion chamber 12 operates at a certain frequency... The transmission loss must be minimized, that is... ,in, Indicates the expansion ratio. The wave number is represented by D, the diameter of the expansion chamber is d, the diameter of the inlet pipe is c, and the velocity of sound in the exhaust gas is c.

[0029] The refrigerant fluid needs to absorb at least the heat load. Calories, ,in, For heat exchange area, The convective heat transfer coefficient on the cold side is... For refrigerant mass flow rate, For the specific heat capacity of the refrigerant, For gas temperature, This refers to the refrigerant inlet temperature.

[0030] Example 3 The marine gas turbine silencing system of the present invention adopts a parallel multi-expansion chamber structure, in which airflow is distributed to multiple parallel expansion chambers, which can effectively reduce the size of a single expansion chamber and achieve system compactness, while increasing the contact area between the outer wall of the expansion chamber and the refrigerant, thereby improving heat exchange efficiency.

[0031] Specifically, the plurality of expansion chambers 12 are a first expansion chamber, a second expansion chamber, and a third expansion chamber arranged in parallel. The inlets of the first expansion chamber, the second expansion chamber, and the third expansion chamber are all connected to the inlet pipe 11, and the outlets of the first expansion chamber, the second expansion chamber, and the third expansion chamber are all connected to the outlet pipe 13. The refrigerant fluid can pass through the first expansion chamber, the second expansion chamber, and the third expansion chamber.

[0032] The airflow in the parallel-connected first, second, and third expansion chambers satisfies the following mass conservation constraints. ,in, For gas density, Let be the airflow velocity in the i-th expansion chamber. Let i be the cross-sectional area of ​​the i-th expansion chamber. The airflow velocity in the main pipe, This is the cross-sectional area of ​​the main pipe; The overall transmission loss of the multiple expansion chambers 12 must meet the following requirements. Wherein, the transmission loss of the i-th expansion chamber is, , in, This represents the expansion ratio of the i-th expansion chamber. Let be the diameter of the i-th expansion chamber. Let be the diameter of the connecting pipe of the i-th expansion chamber. Indicates wave number; The refrigerant fluid needs to absorb at least the heat load. Calories, The overall heat transfer equation of the cooling cavity within the housing 16 in, For refrigerant mass flow rate, For the specific heat capacity of the refrigerant, For gas temperature, This refers to the refrigerant inlet temperature. This refers to the refrigerant outlet temperature. The total heat transfer area is represented by U, and the overall heat transfer coefficient U is obtained through... Obtain, among which, The heat transfer coefficient is the refrigerant side heat transfer coefficient. , For the thermal conductivity of the refrigerant, The hydraulic diameter, For the refrigerant side Nusselt number, This is the heat transfer coefficient on the exhaust side.

[0033] To ensure uniform cooling in each expansion chamber and meet the required temperature distribution within the cooling cavity, , in, This is the highest temperature in the cooling chamber. This is the lowest temperature in the cooling chamber. This is the maximum permissible temperature non-uniformity coefficient.

[0034] By limiting the layout, size, and cooling parameters of multiple side-by-side expansion chambers, the volume is minimized while ensuring sound absorption and cooling performance.

[0035] The control process of the silencing system of this invention uses the exhaust gas temperature of the gas turbine as the core input parameter, and monitors the exhaust gas temperature in real time. To dynamically adjust the refrigerant mass flow rate The control system adopts a feedforward-feedback composite mechanism, where the feedforward part is based on The predicted value is used to adjust the cooling intensity in advance, and the feedback part relies on the expansion chamber wall temperature sensor for closed-loop correction to ensure that the wall temperature is always below the material's temperature resistance limit. Through the above settings, the load fluctuation is effectively dealt with and a stable cooling effect is maintained, thereby preventing high temperature from damaging the soundproofing structure.

[0036] The control logic of the silencing system of this invention is based on the heat balance equation, that is, the heat Q carried away by the refrigerant must match the heat load transferred by the gas, and satisfy the requirement that... ,in For the specific heat capacity of the refrigerant, and These are the refrigerant inlet and outlet temperatures, respectively. The temperature is dynamically adjusted using a proportional-integral-derivative (PID) controller. The system rapidly maintains thermal balance when the exhaust gas temperature changes, ensuring that the acoustic performance of the expansion chamber does not decrease due to thermally induced deformation or material degradation, while avoiding energy loss caused by insufficient or excessive cooling.

[0037] In terms of miniaturization, optimized cooling parameters indirectly support compact design, and precise flow regulation improves cooling efficiency, allowing for minimal transfer losses. Under the premise of ensuring wall temperature safety, the size of the expansion chamber and the thickness of the cooling cavity are reduced, thereby reducing the overall system volume V, eliminating redundant space in traditional designs, and making the equipment more adaptable to the weight and space constraints of marine environments.

[0038] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A high-temperature resistant impedance composite silencer system for marine gas turbines, comprising an impedance composite silencer (100) disposed at the turbine outlet of a marine gas turbine (200), characterized in that: The impedance composite silencer (100) includes a reactive silencer section (10) near the turbine outlet and a resistive silencer section (20) downstream of the reactive silencer section (10). The resistant silencing section (10) includes a housing (16) in which a plurality of expansion chambers (12) are provided. The plurality of expansion chambers (12) are connected to the turbine of the marine gas turbine (200) via inlet pipes (11); The plurality of expansion chambers (12) are connected to the resistive silencing section (20) via outlet pipes (13); The housing (16) is provided with a refrigerant outlet (14) and a refrigerant inlet (15). The refrigerant fluid enters the housing (16) from the refrigerant inlet (15), passes through the plurality of expansion chambers (12) and carries away the heat of the expansion chambers (12) before being discharged from the refrigerant outlet (14). The resistive silencing section (20) is equipped with sound-absorbing louvers lined with metal fibers.

2. The high-temperature resistant impedance composite silencing system according to claim 1, characterized in that: The resistant silencing section (10) includes an expansion chamber (12) and a cooling cavity located between the housing (16) and the expansion chamber (12). The silencing performance is maintained while ensuring thermal management by controlling the refrigerant fluid velocity in the cooling cavity.

3. The high-temperature resistant impedance composite silencing system according to claim 2, characterized in that: A first sensor assembly is installed at the inlet pipe (11) of the resistive noise reduction section (10), and the first sensor assembly monitors the exhaust gas velocity. and exhaust gas temperature ; A second sensor assembly is provided at the refrigerant inlet (15), and the second sensor assembly collects the refrigerant inlet temperature. and the current refrigerant flow rate ; Based on the heat transfer coefficient of the exhaust gas side Assess the current heat load Q and predict the expansion chamber wall temperature. To determine whether the flow rate needs to be adjusted; The controller calculates the required refrigerant flow rate based on the heat balance equation. The controller generates control commands and determines the flow rate adjustment amount. .

4. The high-temperature resistant impedance composite silencing system according to claim 3, characterized in that: The current heat load Q is the heat that the cooling system needs to remove. ， Where Q represents the heat that needs to be transferred. The exhaust gas side convective heat transfer coefficient is... For heat transfer area, To increase the temperature of the expansion chamber wall.

5. The high-temperature resistant impedance composite silencing system according to any one of claims 1-4, characterized in that: The diameter D of the expansion chamber (12) of the resistive silencing section (10), the diameter d of the inlet pipe (11), and the heat exchange area The following constraints must be met; The expansion chamber (12) at frequency The propagation loss under the following conditions is satisfied. ,in, Indicates the expansion ratio. The wave number is represented by c, and the speed of sound in the exhaust gas is c. The refrigerant fluid needs to absorb at least the heat load. Calories, ,in, The convective heat transfer coefficient on the cold side is... For refrigerant mass flow rate, For the specific heat capacity of the refrigerant, For gas temperature, This refers to the refrigerant inlet temperature.

6. The high-temperature resistant impedance composite silencing system according to any one of claims 1-4, characterized in that: The plurality of expansion chambers (12) are a first expansion chamber, a second expansion chamber, and a third expansion chamber arranged in parallel; The inlets of the first expansion chamber, the second expansion chamber, and the third expansion chamber are all connected to the inlet pipe (11), and the outlets of the first expansion chamber, the second expansion chamber, and the third expansion chamber are all connected to the outlet pipe (13). The refrigerant fluid passes through the first expansion chamber, the second expansion chamber, and the third expansion chamber.

7. The high-temperature resistant impedance composite silencing system according to claim 6, characterized in that: The airflow in the parallel-connected first, second, and third expansion chambers satisfies the following mass conservation constraints. ， in, For gas density, Let be the airflow velocity in the i-th expansion chamber. Let i be the cross-sectional area of ​​the i-th expansion chamber. The airflow velocity in the main pipe, This is the cross-sectional area of ​​the main pipe.

8. The high-temperature resistant impedance composite silencing system according to claim 7, characterized in that: The overall transmission loss of the multiple expansion chambers (12) must meet the following requirements: Wherein, the transmission loss of the i-th expansion chamber is, ， in, This represents the expansion ratio of the i-th expansion chamber. Let be the diameter of the i-th expansion chamber. Let be the diameter of the connecting pipe of the i-th expansion chamber. Indicates wave number.

9. The high-temperature resistant impedance composite silencing system according to claim 8, characterized in that: The refrigerant fluid needs to absorb at least the heat load. Calories, The overall heat transfer equation of the cooling cavity within the shell (16) is as follows: in, For refrigerant mass flow rate, For the specific heat capacity of the refrigerant, For gas temperature, This refers to the refrigerant inlet temperature. This refers to the refrigerant outlet temperature. The total heat transfer area is represented by U, and the overall heat transfer coefficient U is obtained through... Obtain, among which, The heat transfer coefficient is the refrigerant side heat transfer coefficient. , For the thermal conductivity of the refrigerant, The hydraulic diameter, For the refrigerant side Nusselt number, This is the heat transfer coefficient on the exhaust side.

10. The high-temperature resistant impedance composite silencing system according to any one of claims 1-4, characterized in that: The resistive silencing section (20) is provided with silencing louvers made of metal fibers, and the silencing louvers form a channel structure to achieve resistive silencing.

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