Arc heater stable air intake device

Abstract

The application discloses an arc heater stable air inlet device, which comprises an air inlet chamber inner sleeve, a flow plug and an air inlet chamber outer sleeve.The air inlet chamber inner sleeve is a circular ring structure, and a plurality of tangential air inlet grooves are formed on the wall surface of the air inlet chamber inner sleeve.The flow plug is a cylinder, and a Laval nozzle structure is arranged in the flow plug.The flow plug is installed in the air inlet grooves of the air inlet chamber inner sleeve, and compressed working gas enters the interior of the arc heater through the tangential air inlet grooves and is ionized to form an arc.The air inlet chamber outer sleeve is a circular ring structure, and is sleeved on the air inlet chamber inner sleeve and fixedly sealed with the air inlet chamber inner sleeve.An air inlet pipe is connected to the outer circle of the air inlet chamber outer sleeve, and is used for connecting high-pressure gas.A cavity is formed between the inner circle of the air inlet chamber outer sleeve and the air inlet chamber inner sleeve, and high-pressure working gas enters the cavity through the air inlet pipe, and then enters the interior of the arc heater through the flow plug.The application can shield the influence of upstream flow field fluctuation of the air inlet device on the interior flow field of the arc heater, reduce the influence of temperature change and airflow on the air inlet device, and further reduce the influence on the operation parameters of the arc heater.

Description

Technical Field

[0001] This invention relates to a stable air intake device for an electric arc heater, belonging to the field of aerospace aerodynamic thermal protection systems. Background Technology

[0002] Arc heaters are core equipment in ground simulation tests of thermal protection for aerospace vehicles both domestically and internationally, and are an important means of addressing ground-based thermal protection assessments for hypersonic vehicles. Currently, the performance requirements for arc heaters are constantly increasing, and arc heaters capable of stable operation at high power for extended periods are urgently needed. At present, during long-term, high-power operation, parameters such as arc chamber pressure and operating power gradually increase over time, causing inconsistencies between the experimental and commissioning states, affecting the assessment results of the vehicle's materials and structure. There are many reasons for this phenomenon, including electrode ablation and fluctuations in airflow, which can all impact the experimental state. Among these, fluctuations in airflow are related to the structural design of the air intake device; therefore, improvements to the arc heater's air intake device are needed to address these issues. Summary of the Invention

[0003] The technical problem to be solved by the present invention is to overcome the shortcomings of the prior art and solve the problem of stable operation of the electric arc heater under long-term and high-power conditions.

[0004] The objective of this invention is achieved through the following technical solutions:

[0005] An arc heater stabilizing air intake device includes:

[0006] The intake chamber is a ring structure with multiple sets of tangential intake slots on the wall.

[0007] The flow plug is cylindrical and has a Laval nozzle structure inside. It is installed in the intake chamber of the intake slot. The compressed working gas enters the arc heater tangentially through it and is ionized to form an electric arc.

[0008] The outer casing of the air intake is a circular structure that fits onto the inner casing of the air intake and is fixed and sealed with it. An air intake pipe is connected to the outer circumference of the outer casing of the air intake for connecting high-pressure gas. There is a cavity between the inner circumference and the inner casing of the air intake. High-pressure working gas enters the air intake cavity through the air intake pipe, and then enters the arc heater after passing through the flow plug.

[0009] Preferably, the outer air intake sleeve is fixed and sealed to the inner air intake sleeve by welding.

[0010] Preferably, the intake pipe is welded onto the outer circumference of the outer casing of the intake manifold.

[0011] Preferably, the number of air inlet slots in the air inlet chamber is determined by the maximum air inlet flow rate of the electric arc heater, and they are arranged in multiple rows in a uniform distribution.

[0012] Preferably, to ensure stable intake flow over a long period of time and prevent cavitation, the intake chamber sleeve is made of a high-hardness metal material.

[0013] Preferably, the inner surface of the flow plug adopts a Laval nozzle structure to ensure a more stable flow field entering the arc heater.

[0014] Preferably, the flow plug is made of ceramic material.

[0015] Preferably, the outer casing of the air intake is designed with cooling water channels to ensure that the radiant temperature of the air intake chamber does not become too high during long-term operation.

[0016] Preferably, the high-pressure working gas enters the arc heater evenly through the flow plug.

[0017] Preferably, the flow plug is used to shield the influence of upstream flow field fluctuations on the internal flow field of the arc heater.

[0018] Compared with the prior art, the present invention has the following advantages:

[0019] The present invention relates to a stable air intake device for an electric arc heater, which, by adding a flow plug component, shields the influence of upstream flow field fluctuations on the internal flow field of the electric arc heater; enhances the cooling design of the air intake device by using a low expansion coefficient material to reduce the impact of temperature changes on the air intake device; and uses a high-hardness material to reduce the erosion of the airflow on the air intake device, thereby ensuring stable air intake flow and reducing the impact on the operating parameters of the electric arc heater. Attached Figure Description

[0020] Figure 1 This is a schematic diagram of the structure of the arc heater stable air intake device shown in this invention.

[0021] Figure 2 This is a schematic diagram of the flow plug structure shown in the invention. Detailed Implementation

[0022] To make the objectives, technical solutions, and advantages of the present invention clearer, the embodiments of the present invention will be described in further detail below with reference to the accompanying drawings.

[0023] An arc heater stabilizing air intake device includes:

[0024] The intake chamber is a ring structure with multiple sets of tangential intake slots on the wall.

[0025] The flow plug is cylindrical and has a Laval nozzle structure inside. It is installed in the intake chamber of the intake slot. The compressed working gas enters the arc heater tangentially through it and is ionized to form an electric arc.

[0026] The outer casing of the air intake is a circular structure that fits onto the inner casing of the air intake and is fixed and sealed to the inner casing of the air intake by welding. An air intake pipe is welded to the outer circle of the outer casing of the air intake for connecting high-pressure gas. There is a cavity between the inner circle and the inner casing of the air intake. High-pressure working gas enters the air intake cavity through the air intake pipe and then enters the arc heater evenly through the flow plug.

[0027] Preferably, in the stable air intake device for the electric arc heater, the number of air intake slots in the air intake chamber should be determined by the maximum air intake flow rate of the electric arc heater, and they should be arranged in multiple rows evenly.

[0028] Preferably, the air intake device for the electric arc heater should be made of a high-hardness metal material to ensure a stable air intake flow over a long period of time and to prevent cavitation.

[0029] Preferably, in the arc heater stabilizing air intake device, the inner surface of the flow plug adopts a Laval nozzle structure to ensure a more stable flow field entering the arc heater.

[0030] Preferably, the arc heater's stable air intake device, in order to ensure a stable air intake flow over a long period of time, and to prevent the throat size of the flow plug from increasing due to cavitation, temperature, or other reasons, requires that the flow plug be made of a high-strength material with a low coefficient of expansion, such as ceramic.

[0031] Preferably, the arc heater has a stable air intake device, and the outer casing of the air intake chamber is designed with cooling water channels to ensure that the radiation temperature of the air intake chamber does not become too high during long-term operation.

[0032] Example:

[0033] like Figure 1 As shown, the arc heater stabilizing air intake device provided in this embodiment of the invention includes:

[0034] The intake chamber is sleeve 1, which has a circular structure and multiple sets of tangential intake slots on the wall surface;

[0035] Flow block 2, such as Figure 2 As shown, it is cylindrical with a Laval nozzle structure inside. It is installed in the intake slot of the intake chamber. The compressed working gas enters the arc heater tangentially through it and is ionized to form an electric arc.

[0036] The outer sleeve 3 of the air intake is a circular structure, which is fitted onto the inner sleeve 1 of the air intake and fixed and sealed to the inner sleeve 1 of the air intake by welding. An air intake pipe is welded on the outer circle of the outer sleeve 3 to connect high-pressure gas. There is a cavity between the inner circle and the inner sleeve 1 of the air intake. High-pressure working gas enters the air intake cavity through the air intake pipe and then enters the arc heater evenly through the flow plug 2.

[0037] It should be noted that the flow plug 2 can be fixed to the inner sleeve 1 of the air intake chamber by means of threads or tight fit. The inner sleeve 1 of the air intake chamber and the outer sleeve 3 of the air intake chamber are connected and sealed by welding, and the connection surface ensures no air leakage at a pressure of 10MPa.

[0038] It should be further explained that the flow plug 2 is a key component to ensure the stable airflow of the arc heater. Its inner surface adopts the Laval nozzle structure and needs to be processed with high strength and low thermal expansion coefficient.

[0039] It should be further explained that during the long-term operation of the electric arc heater, the temperature of the electric arc inside the heater is very high, and it will continuously heat the air intake device through thermal radiation. Therefore, the air intake device needs to be designed with cooling water channels for cooling.

[0040] Specifically, the intake manifold 1 is made of high-strength alloy, the flow plug 2 is made of alumina ceramic material sintered, and the intake manifold 3 is made of stainless steel material.

[0041] The contents not described in detail in this specification are common knowledge to those skilled in the art.

[0042] Although the present invention has been disclosed above with reference to preferred embodiments, it is not intended to limit the present invention. Any person skilled in the art can make possible changes and modifications to the technical solutions of the present invention by utilizing the methods and techniques disclosed above without departing from the spirit and scope of the present invention. Therefore, any simple modifications, equivalent changes and alterations made to the above embodiments based on the technical essence of the present invention without departing from the content of the technical solutions of the present invention shall fall within the protection scope of the technical solutions of the present invention.

Claims

1. A device for stabilizing the air intake of an electric arc heater, characterized in that, include: The intake chamber is a ring structure with multiple sets of tangential intake slots on the wall. The flow plug is cylindrical and has a Laval nozzle structure inside. It is installed in the intake chamber of the intake slot. The compressed working gas enters the arc heater tangentially through it and is ionized to form an electric arc. The outer casing of the air intake is a circular structure that fits onto the inner casing of the air intake and is fixed and sealed with it. An air intake pipe is connected to the outer circumference of the outer casing of the air intake for connecting high-pressure gas. There is a cavity between the inner circumference and the inner casing of the air intake. High-pressure working gas enters the air intake cavity through the air intake pipe, and then enters the arc heater after passing through the flow plug.

2. The stable air intake device according to claim 1, characterized in that, The outer air intake sleeve is fixed and sealed to the inner air intake sleeve by welding.

3. The stable air intake device according to claim 1, characterized in that, The intake pipe is welded onto the outer circumference of the outer casing of the intake manifold.

4. The stable air intake device according to claim 1, characterized in that, The number of air inlet slots in the air inlet chamber is determined by the maximum air inlet flow rate of the electric arc heater, and they are arranged in multiple rows in a uniform distribution.

5. The stable air intake device according to claim 1, characterized in that, To ensure stable airflow over a long period and prevent cavitation, the intake chamber is made of a high-hardness metal material.

6. The stable air intake device according to claim 1, characterized in that, The inner surface of the flow plug adopts a Laval nozzle structure to ensure a more stable flow field entering the arc heater.

7. The stable air intake device according to claim 1, characterized in that, The flow plug is made of ceramic material.

8. The stable air intake device according to claim 1, characterized in that, The outer casing of the air intake is designed with cooling water channels to ensure that the radiant temperature of the air intake chamber does not become too high during long-term operation.

9. The stable air intake device according to any one of claims 1 to 8, characterized in that, High-pressure working gas enters the arc heater evenly through the flow plug.

10. The stable air intake device according to any one of claims 1 to 8, characterized in that, The flow plug is used to shield the upstream flow field fluctuations of the air intake device from the internal flow field of the arc heater.

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