A device for measuring microwave power absorbed by a water load

Abstract

This utility model discloses a device for measuring the microwave power absorbed by a water load, aiming to measure the microwave power absorbed by the water load in real time and adjust the inlet water pressure. The system consists of an inlet water pipe, a water load, a return water pipe, a waveguide transmission line, a computer acquisition card, and an industrial control host computer. The waveguide transmission line is equipped with a directional coupler to assist in measurement and verification. The inlet water pipe can adjust the pressure and stabilize the flow rate. The return water pipe ensures the accuracy of flow rate measurement. The water load is fed from top to bottom to avoid air bubble accumulation and local overheating. The rubber hose buffers thermal expansion and contraction. The industrial control host computer displays data curves such as pressure, flow rate, and temperature in real time and calculates the absorbed power. It has the advantages of accurate measurement, stable pressure regulation, system reliability, and convenient operation.

Description

Technical Field

[0001] This utility model relates to the field of microwave power measurement technology, specifically to a device for measuring the microwave power absorbed by a water load. Background Technology

[0002] In the Experimental Superconducting Tokamak (EAST) nuclear fusion device, low-hybrid current drive (LHCD) is one of the important means for plasma-assisted heating. It consists of a klystron used as a microwave source, a microwave transmission line, and a coupling antenna. The maximum power of a single branch can reach 500 kW, with a frequency of 4.6 GHz and a maximum operating pulse width of >1000 s. The core of tokamak physics experiments lies in the optimization and confinement of plasma. The output power of the low-hybrid system has a significant impact on the acquisition of high-performance plasma and its steady-state operation.

[0003] Therefore, it is essential to establish a high-power microwave power measurement system for low-clutter systems. Currently, there are two main methods for measuring high-power microwave transmission within microwave transmission line waveguides: the water-load absorption method and the directional coupler sampling method. The water-load method measures microwave power primarily by absorbing the microwave energy radiated from the microwave source through a water load; the microwave power absorbed by the water is the output power of the microwave. This method is generally used for system testing and is the most basic and reliable power measurement method.

[0004] Calculating the microwave power absorbed by water requires precise measurement of the water flow rate and the temperature rise at the outlet relative to the inlet. Conventional manual measurements and calculations often fail to reflect real-time power changes. Furthermore, as water temperature rises, fluid flow properties increase, altering the flow rate. This explains the relatively low accuracy and inaccuracy of high-power microwave measurement systems both domestically and internationally. Additionally, the ceramic window components on the water load should be protected from excessive water pressure to prevent deformation or breakage; therefore, the inlet water pressure needs to be appropriately limited and adjusted. Utility Model Content

[0005] The technical problem to be solved by this utility model is: how to accurately measure the water flow rate of the water load and the temperature rise of the outlet relative to the inlet, so as to accurately measure the microwave power to improve the absorption of the water load.

[0006] To solve the above-mentioned technical problems, this utility model provides the following technical solution:

[0007] A device for measuring microwave power absorbed by a water load includes a water load, and an inlet pipe, a return pipe, and a microwave transmission line respectively connected to the water load.

[0008] The inlet of the water inlet pipe is provided with an inlet ball valve, a pressure regulator and an inlet water temperature sensor in sequence facing the outlet. The outlet end of the water inlet pipe is connected to the water load through a flexible hose.

[0009] The return water pipeline is equipped with a return water temperature sensor, a flow sensor, and an outlet ball valve in sequence, with the inlet of the return water pipeline facing the outlet. The inlet end of the return water pipeline is connected to the water load through a flexible hose.

[0010] The input side of the water load is connected to the microwave transmission line.

[0011] Since calculating the microwave power absorbed by water requires accurate measurement of the water flow rate of the water load and the temperature rise of the outlet relative to the inlet, this application sets up an inlet pipe, a return pipe, and a microwave transmission line, which are respectively connected to the water load. Inlet water temperature sensors and return water temperature sensors are set on the inlet pipe and the return pipe, respectively, to detect the temperature difference before and after the water flows through the water load. The inlet pipe can adjust the pressure and stabilize the flow rate, and the return pipe ensures the accuracy of the flow rate measurement. Compared with traditional manual measurement, this application can reflect the changes in temperature difference and water flow rate in real time, thereby improving the measurement accuracy.

[0012] Furthermore, the water inlet pipeline is equipped with a pressure regulating valve and a pressure sensor, which can monitor and adjust the pressure inside the pipeline in real time. The extended water inlet pipeline buffers the flow field, reduces the impact of turbulence, ensures stable flow in the water cooling link, and guarantees that the system operates under safe pressure.

[0013] As a further embodiment of this utility model: the pressure regulating component includes a pressure regulating valve and a pressure sensor, which are installed on the water inlet pipe.

[0014] As a further embodiment of this utility model: the water inlet pipeline uses a water-cooled pipe to sequentially connect the inlet ball valve, the pressure regulating valve, the pressure sensor, and the inlet water temperature sensor; wherein, the pressure regulating valve, the pressure sensor, the inlet water temperature sensor, and the water-cooled pipe are threadedly connected.

[0015] As a further aspect of this utility model, it also includes a computer, which is connected to a pressure sensor, a flow sensor, an inlet water temperature sensor, and an outlet water temperature sensor via coaxial cables.

[0016] As a further aspect of this invention, the pressure sensor is model Burkert 8316.

[0017] As a further embodiment of this utility model: the microwave transmission line includes a directional coupler and a long straight waveguide, the microwave input side of the water load is connected to the long straight waveguide, and the other side of the long straight waveguide is connected to the microwave source klystron through the directional coupler.

[0018] As a further embodiment of this utility model: the inlet of the water load is connected to hose one, and the outlet of the water load is connected to hose two.

[0019] As a further embodiment of this utility model: the return water pipeline uses a water-cooled pipe two to sequentially connect the return water temperature sensor, the flow sensor, and the outlet ball valve; wherein, the return water temperature sensor, the flow sensor, and the tee pipe section are connected by threads.

[0020] As a further aspect of this invention, the flow sensor is model Burkert 8025.

[0021] As a further aspect of this utility model, both the inlet water temperature sensor and the return water temperature sensor are Burkert 8400 models.

[0022] Compared with the prior art, the beneficial effects of this utility model are:

[0023] Since calculating the microwave power absorbed by water requires accurate measurement of the water flow rate of the water load and the temperature rise of the outlet relative to the inlet, this application sets up an inlet pipe, a return pipe, and a microwave transmission line, which are respectively connected to the water load. Inlet water temperature sensors and return water temperature sensors are set on the inlet pipe and the return pipe respectively to detect the temperature difference before and after the water flows through the water load. The inlet pipe can adjust the pressure and stabilize the flow rate, and the return pipe ensures the accuracy of flow rate measurement. Compared with traditional manual measurement, this application can reflect the changes in temperature difference and water flow rate in real time, thereby improving the measurement accuracy of microwave power.

[0024] Furthermore, the inlet pipe is equipped with a pressure regulating valve and a pressure sensor, which can monitor and adjust the pressure inside the pipe in real time. The extended inlet pipe buffers the flow field, reduces the impact of turbulence, ensures stable flow in the water cooling link, and guarantees that the system operates under safe pressure.

[0025] This application can accurately measure the microwave power absorbed by the water load in real time. The directional coupler on the waveguide transmission line can calibrate and verify the measurement results. Combined with multi-sensor data acquisition, it ensures the high accuracy and reliability of microwave power measurement.

[0026] The water load of this application adopts a top-down water inlet method, which avoids the accumulation of air bubbles and local overheating; the rubber hose used for connection can absorb the dimensional changes caused by thermal expansion and contraction, prevent the pipeline from being damaged due to stress concentration, and improve the stability and reliability of the system.

[0027] This application combines an industrial control host computer with a computer acquisition card, connects to multiple sensors and uses voltage signal communication, and can display real-time data curves of pressure, flow, and inlet / outlet water temperature in the water cooling pipeline. It can also automatically calculate the water load absorption power, making it easy for operators to fully understand the system's operating conditions.

[0028] This application uses rubber hoses to connect the inlet or outlet water pipes to the water load. The rubber hoses are flexible, easy to extend and bend at small angles, which facilitates the system installation layout. Each pipe is controlled by a ball valve and a three-way drain valve, which is simple to operate and provides convenience for the use and maintenance of the system. Attached Figure Description

[0029] Figure 1 This is an isometric schematic diagram of the device for measuring microwave power absorbed by water load according to an embodiment of the present invention;

[0030] Figure 2 This is a front view of the water inlet pipe in an embodiment of this utility model;

[0031] Figure 3 This is a front view of the return water pipeline according to an embodiment of this utility model;

[0032] Figure 4 This is a system structure block diagram of the device for measuring microwave power absorbed by water load according to an embodiment of the present invention;

[0033] Explanation of reference numerals in the attached figures:

[0034] 1. Microwave source klystron; 2. Directional coupler; 3. Long straight waveguide; 4. Water load; 5. Inlet ball valve; 6. Three-way drain valve one; 7. Pressure regulating valve; 8. Pressure sensor; 9. Inlet water temperature sensor; 10. Hoses one; 11. Outlet ball valve; 12. Three-way drain valve two; 13. Flow sensor; 14. Return water temperature sensor; 15. Hoses two; 16. Water-cooled pipe one; 17. Water-cooled pipe two. Detailed Implementation

[0035] To make the objectives, technical solutions, and advantages of the embodiments of this utility model clearer, the technical solutions of the embodiments of this utility model will be clearly and completely described below in conjunction with the embodiments of this utility model. Obviously, the described embodiments are only some embodiments of this utility model, not all embodiments. Based on the embodiments of this utility model, all other embodiments obtained by those skilled in the art without creative effort are within the protection scope of this utility model.

[0036] Reference Figure 1 A device for measuring the microwave power absorbed by a water load includes a directional coupler 2, a long straight waveguide 3, a water load 4, an inlet ball valve 5, a three-way drain valve 6, a pressure regulating valve 7, a pressure sensor 8, an inlet water temperature sensor 9, a hose 10, an outlet ball valve 11, a three-way drain valve 12, a flow sensor 13, a return water temperature sensor 14, a hose 15, a water-cooled pipe 16, and a water-cooled pipe 17.

[0037] Reference Figure 1The directional coupler 2 and the long straight waveguide 3 form a microwave transmission line. The microwave input side of the water load 4 is connected to the long straight waveguide 3, and the other side of the long straight waveguide 3 is connected to the microwave source klystron 1 through the directional coupler 2.

[0038] Reference Figure 2 The inlet water pipeline consists of ball valve 5, three-way drain valve 6, pressure regulating valve 7, pressure sensor 8, inlet water temperature sensor 9, and water cooling pipe 16.

[0039] Reference Figure 3 The return water pipeline consists of a ball valve 11 at the outlet, a three-way drain valve 12, a flow sensor 13, a return water temperature sensor 14, and a water-cooled pipe 17. The drain end of the inlet pipeline is connected to the inlet of the water load 4 via a hose 10, and the inlet end of the outlet pipeline is connected to the outlet of the water load 4 via a hose 15.

[0040] Reference Figure 1 and Figure 2 The water inlet pipe is connected to the water-cooled inlet A, and passes through the inlet ball valve 5, the three-way drain valve 6, the pressure regulating valve 7, the pressure sensor 8 and the inlet water temperature sensor 9 in sequence. All components are connected by the water-cooled pipe 16, which is a DN50 stainless steel water-cooled pipe.

[0041] The water-cooled pipe 16 is equipped with a tee section welded using a special process. The pipe section has internal threads. The tee drain valve 6, pressure sensor 8, and inlet water temperature sensor 9 are connected to the water-cooled pipe 16 via threads, facilitating future maintenance and replacement. The end of the inlet pipe is connected to the inlet of the water load 4 via a flexible hose 10, which is a DN25 rubber hose.

[0042] It should be noted that pressure sensor 8 is an insertion type, with the pressure tap direction perpendicular to the fluid flow direction. The installation position is located on the straight pipe section of water-cooled pipe 16. Upstream, a straight pipe section with a diameter greater than 10 times is reserved and it is far from the pressure regulating valve. Downstream, a straight pipe section with a diameter greater than 5 times is reserved and it is far from the pipe bend, ensuring the accuracy of the measurement data.

[0043] Reference Figure 1 and Figure 3 The outlet of the water load 4 is connected to the return water pipeline through the second hose 15, and passes through the return water temperature sensor 14, the flow sensor 13, the three-way drain valve 12 and the outlet ball valve 11 in sequence. The components are connected by the second water cooling pipe 17. The second hose 15 is a DN25 rubber hose, and the second water cooling pipe 17 is a DN50 stainless steel water cooling pipe.

[0044] It should be noted that the water-cooled pipe 2 17 has a tee section welded in by process welding. The pipe section has internal threads, and the return water temperature sensor 14, flow sensor 13, and tee drain valve 2 12 are connected to the water-cooled pipe 2 17 via these threads. The cooling water flowing through the system finally flows out from the water-cooled outlet B (refer to...). Figure 1 ).

[0045] It should be noted that straight pipe sections with a diameter greater than 10 times are reserved upstream and downstream of the installation location of flow sensor 13, which can effectively avoid flow instability and measurement errors caused by bends and valves.

[0046] Reference Figure 1 The inlet water temperature sensor 9 and the return water temperature sensor 14 are inserted into the water. The sensor's temperature probe is perpendicular to the water flow direction and is completely immersed in the fluid. They are respectively arranged at key points for monitoring heat dissipation. The inlet water temperature sensor 9 is located in the inlet pipe near the water inlet of the water load 4, and the return water temperature sensor 14 is located in the return water pipe near the water outlet of the water load 4, which helps to obtain accurate temperature rise change data.

[0047] Reference Figure 4 Pressure sensor 8, flow sensor 13, inlet water temperature sensor 9 and return water temperature sensor 14 are connected to the computer via coaxial cables. The computer includes a computer acquisition card and an industrial control host computer.

[0048] Reference Figure 1 The pressure sensor 8 is a Burkert 8316, the flow sensor 13 is a Burkert 8025, and both the inlet water temperature sensor 9 and the return water temperature sensor 14 are Burkert 8400s. All of these sensors have a built-in 4-20mA sampling output, which is converted to a 0-10V voltage signal after passing through a current-voltage transmitter. These signals are then connected to the computer acquisition card via coaxial cables. It should be noted that the sensor models provided in this application are all commonly available models and are provided for reference only. The computer acquisition card is an NI 6259, installed in the universal slot of a NIPXIe-8840 industrial control host computer. The industrial control host computer receives the acquired signals and updates and displays them in real time.

[0049] All components in this application can be disassembled and replaced at any time, such as various sensors, inlet pipes, return pipes, hoses, etc. It is also applicable to other high-power microwave tubes that require microwave load and power measurement, except for the microwave source klystron 1. By closing the inlet ball valve 5 and the outlet ball valve 11, and opening the three-way drain valve 6 and the three-way drain valve 12, the water-cooling medium in the inlet and return pipes can be drained, at which point the components in the system can be replaced and maintained.

[0050] This application calculates the microwave power absorbed by the water, which requires accurate measurement of the water flow rate of the water load and the temperature rise of the outlet relative to the inlet. The formula for calculating the microwave power absorbed by the water load is as follows:

[0051] P=C×Q×d×δ

[0052] Where P is the microwave power absorbed by the water, in W or kW;

[0053] C is the specific heat capacity of water, measured in J / (kg×℃), which is 4186 J / (kg×℃) under standard atmospheric pressure.

[0054] Q is the water flow rate, measured in m³ / s, and is obtained by flow sensor 13.

[0055] d is the density of water, measured in kg / m³, which is 1 kg / m³ under standard atmospheric pressure.

[0056] δ is the water temperature rise, in °C, obtained by calculating the difference between the return water temperature sensor 14 and the inlet water temperature sensor 9.

[0057] The specific operating principle of this application is as follows:

[0058] After the microwave source klystron 1 is installed, the system starts to work. Open the inlet ball valve 5 and the outlet ball valve 11, and close the three-way drain valve 1 6 and the three-way drain valve 2 12. The experimental operator adjusts the pressure regulating valve 7 according to the maximum pressure bearing index of the water load. The water pressure in the pipeline measured by the pressure sensor 8 can be observed in real time through the industrial control host computer program interface.

[0059] The microwave energy output from the microwave source klystron 1 is absorbed by the water load 4 after passing through the directional coupler 2 and the long straight waveguide 3 on the microwave transmission line. The external circulating cooling water enters the inlet pipe from the water-cooled inlet A. After passing through the pressure regulating valve 7, the water flows at a certain velocity and flows into the inlet of the water load 4 through the hose 10. The water flowing through the water load 4 is heated by microwaves and flows out from the outlet. After passing through the hose 15, it flows into the return water pipe and finally flows back into the external circulating cooling water from the water-cooled outlet B.

[0060] During this process, the flow data measured by the flow sensor 13, the inlet water temperature measured by the inlet water temperature sensor 9, and the return water temperature measured by the return water temperature sensor 14 can be observed in real time on the industrial control host computer program interface. The current microwave power is automatically calculated by the industrial control host computer according to the water load absorption method calculation formula. The calculated microwave power can be compared and verified with the result measured by the directional coupler 2.

[0061] The above embodiments are only used to illustrate the technical solutions of this utility model, and are not intended to limit it. Although this utility model has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of this utility model.

Claims

1. A device for measuring the microwave power absorbed by a water load, characterized in that, It includes a water load, as well as an inlet water pipe, an outlet water pipe, and a microwave transmission line, which are respectively connected to the water load; The inlet of the water inlet pipe is provided with an inlet ball valve (5), a pressure regulator and an inlet water temperature sensor (9) in sequence facing the outlet. The outlet end of the water inlet pipe is connected to the water load (4) through a hose (10). The return water pipeline is provided with a return water temperature sensor (14), a flow sensor (13) and an outlet ball valve (11) in sequence facing the outlet. The inlet end of the return water pipeline is connected to the water load (4) through a second flexible hose (15). The input side of the water load (4) is connected to the microwave transmission line.

2. A device for measuring the absorption of microwave power by a water load as claimed in claim 1, characterized in that: The pressure regulating component includes a pressure regulating valve (7) and a pressure sensor (8), which are installed on the water inlet pipe.

3. A device for measuring the absorption of microwave power by a water load as claimed in claim 2, characterised in that: The water inlet pipeline is connected in sequence to the water inlet ball valve (5), pressure regulating valve (7), pressure sensor (8) and water inlet temperature sensor (9) via a water-cooled pipe (16); wherein the pressure regulating valve (7), pressure sensor (8), water inlet temperature sensor (9) are threadedly connected to the water-cooled pipe (16).

4. A device for measuring the absorption of microwave power by a water load as claimed in claim 2, characterized in that: It also includes a computer, which is connected to a pressure sensor (8), a flow sensor (13), an inlet water temperature sensor (9), and an outlet water temperature sensor (14) via coaxial cables.

5. A device for measuring the absorption of microwave power by a water load as claimed in claim 2, characterized in that: The pressure sensor (8) is a Burkert 8316.

6. A device for measuring the absorption of microwave power by a water load as claimed in claim 1, characterized in that: The microwave transmission line includes a directional coupler (2) and a long straight waveguide (3). The microwave input side of the water load (4) is connected to the long straight waveguide (3), and the other side of the long straight waveguide (3) is connected to the microwave source klystron (1) through the directional coupler (2).

7. A device for measuring the water load absorption of microwave power as defined in claim 1, wherein: The inlet of the water load (4) is connected to hose one (10), and the outlet of the water load (4) is connected to hose two (15).

8. A device for measuring the absorption of microwave power by a water load as claimed in claim 1, characterized in that: The return water pipeline uses a water-cooled pipe two (17) to connect the return water temperature sensor (14), the flow sensor (13), and the outlet ball valve (11) in sequence; wherein the return water temperature sensor (14), the flow sensor (13), and the tee pipe section are connected by threads.

9. The device for measuring microwave power absorbed by a water load according to claim 1, characterized in that: The flow sensor (13) is a Burkert 8025.

10. A device for measuring the absorption of microwave power by a water load as claimed in claim 1, characterized in that: Both the inlet water temperature sensor (9) and the return water temperature sensor (14) are Burkert 8400 models.

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