Direct-current evaporative cooling simulated electric load system and control method

Abstract

The present application relates to a direct-current evaporative cooling simulated electric load system, comprising: a water storage unit, which is configured to store water to be supplied; a water supply unit, which is configured to provide a water supply pressure and regulate a water supply flow rate that is provided from the water storage unit to a direct-current evaporation unit; the direct-current evaporation unit, which is configured to provide a simulated load, use heat generated by the simulated load to convert supplied water into steam, and discharge the steam to the outside; and a control unit, which is configured to control the operation of components of the direct-current evaporative cooling simulated electric load system, wherein the control unit adjusts a flow-regulating valve in the water supply unit to match the water supply flow rate with a loading power of the direct-current evaporation unit, and the temperature of the direct-current evaporation unit is also controlled within a required interval range. In addition, the present application further relates to a corresponding control method for a direct-current evaporative cooling simulated electric load system.

Description

A DC evaporative heat dissipation simulated electric load system and control method Technical Field

[0001] This application relates to the field of aircraft flight testing. Specifically, it relates to a DC evaporative cooling simulated electric load system used during the aircraft's flight testing phase (particularly during power and power test phases, where excess aircraft electrical energy is consumed to fully load the power system generator output), and a control method for the DC evaporative cooling simulated electric load system. Background Art

[0002] As we all know, before a new aircraft officially enters commercial service, it must undergo a series of flight tests to verify that it meets airworthiness regulations. Among these, flight tests related to the performance of the power plant and electrical system require that the power system generator output power reach full load during the test flight. Because the onboard electrical equipment of the test aircraft consumes relatively little power, it is impossible for the generator to meet the test state requirements. Therefore, a simulated electrical load system is required. By connecting a simulated load, the generator consumes the remaining power. Based on the power changes of the aircraft's actual electrical equipment, the simulated load is controlled to connect or disconnect from the aircraft's power grid, adjusting the generator output power to meet the test state requirements.

[0003] However, the simulated load has high power and long loading time, and will generate a large amount of heat during operation. In order to avoid the impact of heat on the aircraft cabin environment, how to dissipate heat becomes the key to the design of the simulated electric load system.

[0004] Because water is readily available, has a large specific heat capacity, and absorbs a large amount of heat when vaporized, evaporative cooling based on a water medium is an ideal heat dissipation method for high-power, long-duration simulated electrical load systems. Therefore, traditional simulated electrical load systems typically use a pool-boiling evaporative cooling solution based on an evaporator. This heat dissipation is achieved by heating the water in the evaporator until it vaporizes and discharges it outside the cabin. Specifically, the volumetric evaporative cooling solution uses pool boiling evaporation. Its advantages are a mature solution and simple principle. Its disadvantages are a complex structure, many components, low heat transfer efficiency, and large size. The evaporator contains a large amount of high-temperature, high-pressure liquid, which is greatly affected by the aircraft's attitude. Liquid level measurement is also required during use. The electric heating tube is in direct contact with the water, and each electric heating tube joint has the risk of leakage. Therefore, it has a high safety risk.

[0005] Summary of the Invention

[0006] The present application provides a direct current evaporation solution with a simple and compact structure, high heat transfer efficiency, and accurate water supply based on loaded power and temperature feedback.

[0007] According to a first aspect of the present application, a DC evaporative heat dissipation simulated electric load system is provided, comprising:

[0008] a water storage unit configured to store water to be supplied;

[0009] a water supply unit configured to provide water supply pressure and adjust the water supply flow rate provided from the water storage unit to the direct current evaporation unit;

[0010] a direct current evaporation unit configured to provide a simulated load and convert the supplied water into water vapor using heat from the simulated load and discharge the steam to the outside of the machine; and

[0011] A control unit configured to control the operation of various components of the DC evaporative heat dissipation simulated electric load system;

[0012] The control unit adjusts the flow regulating valve in the water supply unit to match the water supply flow rate with the load power of the direct current evaporation unit and the temperature of the direct current evaporation unit is also controlled within a required range.

[0013] According to a second aspect of the present application, a control method for the DC evaporative heat dissipation simulated electric load system according to the first aspect is provided, comprising:

[0014] Under the control of the control unit:

[0015] Open the water outlet valve in the water storage unit;

[0016] Start the water supply pump of the water supply unit to generate pressure, so that the water in the water storage tank is continuously pumped to each direct current evaporator through the flow output path composed of a flow sensor and a flow regulating valve connected in series;

[0017] The electric heating tubes in the DC evaporator are turned on according to the loading power requirement to provide a simulated load;

[0018] The heat generated by the electric heating tube when loaded with power is transferred to the evaporation tube via the heat carrier;

[0019] The evaporation tube is heated by the heat, so that the water flowing through the evaporation tube is heated to vaporize and form water vapor;

[0020] The water vapor in the evaporation pipe is discharged to the atmosphere outside the cabin through the steam discharge port;

[0021] The control unit adjusts the flow regulating valve in the water supply unit to match the water supply flow rate with the loading power, and the temperature of the direct current evaporator is also controlled within a required range.

[0022] This Summary is provided to introduce some concepts in a simplified form that are further described below in the Detailed Description. This Summary is not intended to identify key features or essential features of the claimed subject matter, nor is it intended to be used to limit the scope of the claimed subject matter. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] In order to illustrate the manner in which the above-described and other advantages and features of the present application can be obtained, a more particular description of the present application, which has been briefly described above, will be presented by reference to specific embodiments of the present application that are illustrated in the accompanying drawings. Understanding that these drawings depict only typical embodiments of the present application and are therefore not to be considered limiting of its scope, the present application will be described and explained with additional specificity and detail through the use of the accompanying drawings, in which:

[0024] FIG1 shows a schematic top view of the structure of a DC evaporative heat dissipation simulated electric load system according to an embodiment of the present application.

[0025] FIG2 shows a front view schematically showing the specific structure of the DC evaporator in the DC evaporation heat dissipation simulated electric load system shown in FIG1 .

[0026] FIG3 shows a flowchart of a schematic control method for a DC evaporative heat dissipation simulated electric load system according to an embodiment of the present application. DETAILED DESCRIPTION

[0027] In order to solve the above-mentioned problems in the prior art, the present application provides a DC evaporation heat dissipation simulated electric load system, which adopts a DC evaporation scheme based on an evaporation tube. Compared with the pool boiling evaporation scheme based on an evaporation tank, the DC evaporation scheme of the present application has a simple and compact structure, high heat transfer efficiency, and the amount of water can be accurately supplied according to the loaded power and temperature feedback. It solves many problems of the pool boiling evaporation scheme, such as the large volume of the evaporation tank, the presence of a large amount of high-temperature boiling liquid in the tank, the high-temperature boiling liquid in the tank being greatly affected by the aircraft attitude during flight, and high safety risks.

[0028] The solution of the present application is described in detail below with reference to the preferred embodiment given in FIG1 .

[0029] The schematic structure of the DC evaporation heat dissipation simulated electric load system of the present application is shown in FIG1 , which mainly includes three parts: a water storage unit 10 , a water supply unit 20 and a DC evaporation unit 30 .

[0030] The water storage unit 10 is primarily configured to store water to be supplied. Specifically, it comprises a water tank 13, an inlet valve 12, an outlet valve 14, a water supply port 11, and pipes connecting these components. The water tank 13 stores water to be supplied to the direct current evaporation unit 30. The inlet valve 12 and outlet valve 14 are located at either end of the water tank 13, respectively, to control the flow of water into and out of the tank 13. The volume and number of water tanks 13 can be configured based on water storage requirements. This storage requirement is dependent on factors such as the simulated load power applied by the simulated electrical load system during testing and the duration of the load test. In principle, the greater the simulated load power and the longer the load duration, the larger or more water tanks 13 will be required. This can be designed based on the actual flight load test requirements and the aircraft's spatial layout requirements.

[0031] Furthermore, the water inlet valve 12 is connected to the water replenishment port 11 via a pipe. Therefore, when the water level in the water tank 13 falls below a predetermined value, water can be replenished through the water replenishment port 11, thereby preventing the water tank 13 from drying out. Furthermore, this water replenishment mechanism can also reduce the volume and number of water tanks 13 to a certain extent. The predetermined value can be set according to actual needs, for example, 20%.

[0032] The water supply unit 20 is primarily configured to provide water pressure and regulate the flow rate of water supplied from the water storage unit 10 to the direct current evaporation unit 30. The water supply unit 20 includes a water supply pump 21, a relief valve 22, a pressure sensor 23, a flow sensor 24, a flow control valve 25, and pipes connecting these components. The water supply pump 21 is connected to the outlet valve 14 of the water storage tank 13 via a pipe to provide water pressure. The relief valve 22 is connected to both ends of the water supply pump 21 to maintain a constant output pressure. The pressure sensor 23 is connected to the outlet of the water supply pump 21 to measure the output pressure. A flow sensor 24 and a flow control valve 25 connected in series to the outlet of the water supply pump 21 form a flow output path. The flow control valve 25 regulates the water flow rate, while the flow sensor 24 measures the water flow rate in real time. It should be understood that while three flow output paths are shown in Figure 1, this number is for illustrative purposes only and is not intended to be limiting. The specific number of flow output channels can be configured based on the actual needs of the flight test. For example, the specific number of flow output channels is related to factors such as the simulated load power applied by the simulated electrical load system during the test and the duration of the load test, and can be adaptively modified based on specific circumstances.

[0033] The DC evaporation unit 30 is primarily configured to utilize heat from the simulated load to convert the supplied water into steam and discharge it externally. The DC evaporation unit 30 comprises one or more DC evaporators and a connected one-way valve 38. As shown in Figure 2, the exemplary DC evaporation unit 30 includes three DC evaporators 30-1, 30-2, and 30-3. It should be understood that while three DC evaporators 30-1, 30-2, and 30-3 are shown in Figure 1, this number is for illustrative purposes only and is not intended to be limiting. The specific number of DC evaporators can be configured based on the actual requirements of the flight test. For example, the number and size of the DC evaporators are related to factors such as the simulated load power applied by the simulated electrical load system during the test and the duration of the load test, and can be adjusted adaptively based on specific circumstances. Generally, the number of DC evaporators corresponds to the number of flow output paths, as shown in Figure 1, allowing for comprehensive consideration and design.

[0034] Figure 2 illustrates an example structure of a DC evaporator. As shown, the DC evaporator comprises an electric heating pipe 31, an evaporation pipe 32, a heat transfer medium 33, thermal insulation material 34, a temperature sensor 35, a pressure regulating valve 36, a steam exhaust port 37, and the pipes connecting these components. The electric heating pipe 31 and the evaporation pipe 32 are installed within the heat transfer medium 33 using a molding process such as casting. The electric heating pipe 31 provides a simulated load, consuming excess aircraft power. The power load is determined by the remaining power in the aircraft's power system. The evaporation pipe 32 provides a heat exchange channel for water evaporation, allowing the water within the pipe to fully absorb heat. The heat transfer medium 33 is made of a metal material with good thermal conductivity and transfers heat from the electric heating pipe to the evaporation pipe 32. The thermal insulation material 34 prevents heat from dissipating from the heat transfer medium 33 into the passenger cabin, while also maintaining the surface temperature of the DC evaporation unit 30 within an appropriate range to prevent burns. The pressure regulating valve 36 controls the pressure within the evaporation pipe 32 to adjust the evaporation efficiency. The steam exhaust port 37 is in communication with the atmosphere outside the aircraft cabin and is used to discharge the hot steam outside the aircraft.

[0035] The water inlet of the direct current evaporator is connected to the flow output of the water supply unit 20 through a one-way valve 38. The one-way valve 38 is used to supply water to the evaporation tube 32 while preventing the water or steam in the evaporation tube 32 from flowing in the reverse direction.

[0036] In addition to the components shown in Figures 1 and 2, it should be understood that there is also a control unit (not shown) that controls the operation of the various components of the DC evaporative heat dissipation simulated electric load system as a whole. The control unit communicates with the corresponding components of the DC evaporative heat dissipation simulated electric load system via cables to send and / or receive data and instructions. Specifically, the control unit receives sensor data from various sensors (such as pressure sensor 23, flow sensor 24, temperature sensor 35...), analyzes these sensor data, and sends control instructions to the corresponding components (such as flow control valve 25, pressure control valve 36, etc.) based on the results of the analysis to adjust the flow and pressure, so that the system can operate normally. The specific functions of the control unit will be specifically explained in conjunction with the following example control process of the DC evaporative heat dissipation simulated electric load system.

[0037] The control method flow of an example thereof will be specifically described below with reference to the schematic structure of the DC evaporative heat dissipation simulated electric load system shown in FIG. 1 and FIG. 2 , as shown in FIG. 3 .

[0038] When the system starts working, under the control of the control unit:

[0039] First, in step 302 , the water outlet valve 14 in the water storage unit 10 is opened.

[0040] Subsequently, in step 304, the water supply pump 32 of the water supply unit 20 is started to generate pressure, thereby continuously pumping the water in the water storage tank 13 to each direct current evaporator 30-1, 30-2 and 30-3 through a flow output path composed of a flow sensor 24 and a flow regulating valve 25 connected in series.

[0041] Next, in step 306 , the electric heating tube 31 in the direct current evaporator is turned on according to the loading power requirement to provide a simulated load.

[0042] Then, in step 308 , the heat generated by the electric heating tube 31 when the power is applied is transferred to the evaporation tube 32 via the heat carrier 33 .

[0043] Then, in step 310 , the evaporation tube 32 is heated by heat to increase its temperature, so that the water flowing through the evaporation tube 32 is heated to vaporize and form water vapor.

[0044] Finally, in step 312 , the water vapor in the evaporation pipe 32 is discharged to the atmosphere outside the cabin through the steam exhaust port 37 .

[0045] When the DC evaporative cooling simulated electric load system starts operating (performing the above steps), a flow monitoring step 314 is also provided, that is, the control unit performs corresponding analysis based on the real-time measured water supply flow data from the flow sensor 24, the loading power of the DC evaporator, and the temperature feedback data from the temperature sensor 35 to obtain a target water supply flow that can match the water supply flow and the loading power of the DC evaporation unit and control the temperature within the required range, and achieves the target water supply flow by adjusting the flow control valve 25.

[0046] For example, if the load power is W (unit: kW), the heat of vaporization of water is K (unit: kJ / kg), the corresponding boiling point is T, and the temperature increment is expressed as ΔT, then the basic water supply flow rate q is calculated as: q = W / K (unit: kg / s).

[0047] After determining the base water flow rate q, it is necessary to fine-tune it based on the measured temperature within the DC evaporator to ensure that the temperature remains within the specified range. If the measured temperature exceeds T + ΔT, meaning the DC evaporator temperature exceeds the boiling point by a predetermined temperature increment, this indicates that the evaporation rate within the DC evaporator exceeds the water supply, generating superheated steam. Therefore, the base water flow rate q needs to be appropriately increased.

[0048] Similarly, when the detected temperature is lower than T-ΔT, this indicates that the water supply in the DC evaporator exceeds the evaporation capacity, resulting in insufficient evaporation and a decrease in its internal temperature. Therefore, it is necessary to appropriately reduce the basic water supply flow rate q.

[0049] The fine-tuned base water flow rate q is the target water flow rate. By adjusting the water flow rate as described above, the temperature can be balanced within the range of T-ΔT and T+ΔT. It should be understood that the temperature increment ΔT can be set based on actual needs. Designers can set the acceptable temperature variation range based on factors such as flight test requirements, the volume and power of the DC evaporator, and other factors.

[0050] Thus, by using the adjusted target water flow rate, the heat generated by the electric heating tubes 31 in the DC evaporator and the heat dissipated by evaporation are maintained in balance. Specifically, the amount of liquid water entering the evaporation tubes 32 per unit time is balanced with the amount of water vapor converted after heating. Furthermore, since the evaporation tubes 32, containing only a small amount of high-temperature, boiling water, are completely enclosed within the heat carrier 33, which is in turn isolated from the cabin environment by thermal insulation 34, the DC evaporative heat dissipation simulated electric load system exhibits excellent safety and reliability.

[0051] The flow monitoring step 314 can be performed periodically at a certain time interval during the entire working phase of the DC evaporative heat dissipation simulated electric load system to achieve a dynamic balance between the heat generated by the electric heating tube 31 and the evaporative heat dissipation.

[0052] In a preferred embodiment, the control method may also include a water replenishment step (not shown in FIG. 3 ). In this step, the control unit determines whether the water level in the water tank 13 of the water storage unit 10 has reached a predetermined level. If the water level in the water tank 13 is below the predetermined level, the control unit sends an open command to the water replenishment interface 11 to replenish the water tank 13. This step can be performed periodically, for example at a certain time interval, throughout the operation of the DC evaporative cooling simulated electric load system to ensure timely replenishment of the water tank 13 and prevent the system from "dry-boiling."

[0053] Furthermore, in another preferred embodiment, the control method may further include a pressure regulation step (not shown in FIG. 3 ), whereby the control unit may adjust the pressure within the evaporation tube 32 by adjusting the pressure regulating valve 36 to change the evaporation efficiency. For example, if the simulated load power in a new flight test is higher, the pressure within the evaporation tube 32 may be increased by adjusting the pressure regulating valve 36 (thereby accelerating the flow and discharge rate of water vapor) to improve the evaporation efficiency. At this point, the control unit will also execute the flow monitoring step 314 to obtain a new target water supply flow rate, ensuring that the water supply flow rate matches the load power and the temperature is controlled within the required range. Conversely, if the simulated load power in the new flight test is lower, the pressure within the evaporation tube 32 may be reduced by adjusting the pressure regulating valve 36 (thereby slowing the flow and discharge rate of water vapor) to reduce the evaporation efficiency. At this point, the control unit will again execute the flow monitoring step 314 to obtain a new target water supply flow rate, ensuring that the water supply flow rate matches the load power and the temperature is controlled within the required range.

[0054] It is not difficult to understand from the above explanations and illustrations that the direct current evaporative heat dissipation solution of the present application adopts flow boiling evaporation, which has the advantages of simple and compact structure, high heat transfer efficiency, no large amount of high-temperature liquid, and little impact from the aircraft attitude. When in use, it is only necessary to monitor the temperature without measuring the liquid level. The evaporating tube and the electric heating tube are integrally cast in the heat carrier, and will not break or leak, and the reliability and safety are relatively high.

[0055] Furthermore, by using the DC evaporative heat dissipation simulated electric load system of this application, the large amount of heat generated during loading is converted into water vapor and dissipated into the atmosphere. Furthermore, the evaporator tube and electric heating tube are integrally cast and enclosed within a heat carrier (which is in turn enclosed within a thermal insulation material), leaving only a small amount of high-temperature, boiling water within the tube. Therefore, during intense maneuvers during a test flight, the center of gravity of the entire DC evaporation unit will not significantly shift, thus avoiding potential hazards. Therefore, compared to traditional pool-boiling evaporative heat dissipation solutions based on evaporation tanks, this system is smaller, requires fewer joints, and offers improved safety and reliability.

[0056] Although various embodiments have been described above, it should be understood that they are intended to be illustrative only and not limiting. Persons skilled in the relevant art(s) will appreciate that various modifications may be made in form and detail without departing from the spirit and scope of the present application as defined by the appended claims. Therefore, the breadth and scope of the present application as disclosed herein should not be limited by the exemplary embodiments disclosed above, but should be defined only in accordance with the appended claims and their equivalents.

Claims

1. A DC evaporation heat dissipation type analog electrical load system, comprising: A water storage unit configured to store water to be supplied; A water supply unit configured to provide water supply pressure and regulate the water supply flow rate supplied from the water storage unit to the DC evaporation unit; A DC evaporation unit configured to provide an analog load and convert the water supply into water vapor using the heat from the analog load and discharge it to the outside of the machine; And A control unit configured to control the operation of each component of the DC evaporation heat dissipation type analog electrical load system; Wherein, the control unit makes the water supply flow rate match the loading power of the DC evaporation unit by adjusting the flow regulating valve in the water supply unit, and the temperature of the DC evaporation unit is also controlled within the required range.

2. The DC evaporation heat dissipation type analog electronic load system according to claim 1, wherein Wherein the water storage unit includes a water storage tank, a water inlet valve, a water outlet valve, and a water replenishment interface; The water supply unit includes a water supply pump, an overflow valve, a pressure sensor, a flow sensor, and a flow regulating valve; and The DC evaporation unit includes a DC evaporator and a check valve connected to the DC evaporator, and the DC evaporator includes an electric heating tube, an evaporation tube, a heat carrier, a heat insulating material, a temperature sensor, a pressure regulating valve, and a steam discharge port.

3. The DC evaporation heat dissipation type analog electronic load system according to claim 2, characterized in that, Wherein the control unit analyzes the real-time measured water supply flow rate data from the flow sensor, the loading power of the DC evaporator, and the temperature feedback data from the temperature sensor to obtain the target water supply flow rate, and adjusts the flow regulating valve to reach the target water supply flow rate.

4. The DC evaporation heat dissipation type analog electronic load system according to claim 2, characterized in that Wherein the control unit determines whether the water level in the water storage tank in the water storage unit reaches a predetermined level, and if the water level in the water storage tank is lower than the predetermined level, the control unit sends an opening instruction to the water replenishment interface to replenish water to the water storage tank.

5. The DC evaporation heat dissipation type analog electronic load system according to claim 2, wherein The control unit controls the pressure in the evaporation tube by adjusting the pressure regulating valve to change the evaporation efficiency.

6. A control method for a DC evaporation heat dissipation type analog electrical load system according to any one of claims 1-5, comprising: Under the control of the control unit: Open the water outlet valve in the water storage unit; Start the water supply pump of the water supply unit to generate pressure, so as to continuously pump the water in the water storage tank to each DC evaporator through a flow output path composed of a series connection of a flow sensor and a flow regulating valve; The electric heating tubes in the DC evaporator are turned on according to the loading power requirement to provide an analog load; The heat generated by the electric heating tubes at the loading power is transferred to the evaporation tube through the heat carrier; The evaporation tube is heated by the heat, so that the water flowing through the evaporation tube is heated to vaporize to form water vapor; The water vapor in the evaporation tube is discharged to the outside atmosphere through the steam discharge port; Wherein the control unit makes the water supply flow rate match the loading power by adjusting the flow regulating valve in the water supply unit, and the temperature of the DC evaporator is also controlled within the required range.

7. The method according to claim 6, characterized in that, The control unit analyzes the real-time measured water supply flow rate data from the flow sensor, the loading power of the DC evaporator, and the temperature feedback data from the temperature sensor to obtain the target water supply flow rate, and adjusts the flow regulating valve to reach the target water supply flow rate.

8. The method according to claim 6, wherein The control unit determines whether the water level in the water storage tank of the water storage unit reaches a predetermined level, and if the water level in the water storage tank is lower than the predetermined level, the control unit sends an opening instruction to the water replenishment interface to replenish water for the water storage tank.

9. The method according to claim 6, characterized in that, The control unit controls the pressure in the evaporation tube by adjusting the pressure regulating valve in the DC evaporator to change the evaporation efficiency.

Images