A high-temperature water vapor gas film drag reduction measurement test device and test method

Abstract

The application provides a high-temperature water vapor gas film drag reduction measurement test device and a test method. The test device comprises an air supply system, a test model and a collection system. The air supply system and the collection system are connected with the test model respectively, and the test model is installed in a water tunnel. The air supply system comprises a steam generator, a steam pressure reducing valve, a high-temperature vortex flowmeter and a high-temperature and high-pressure steam pipe. The steam pressure reducing valve is communicated with the steam generator and the high-temperature vortex flowmeter through the high-temperature and high-pressure steam pipe. The high-temperature vortex flowmeter is communicated with the test model through the high-temperature and high-pressure steam pipe. The collection system comprises a force measuring balance, a data collection card and a collection computer. The force measuring balance is located in the test model and connected with the data collection card. The collection computer is connected with the data collection card. The application can solve the technical problem that the high-temperature water vapor gas film drag reduction test cannot be realized in the prior art.

Description

Technical Field

[0001] This invention relates to the field of underwater drag reduction technology, and in particular to a test device and method for measuring drag reduction through a high-temperature water vapor film. Background Technology

[0002] Drag reduction is a crucial aspect of underwater vehicle design. To maximize endurance, minimizing drag is a key design focus, and ventilation-based drag reduction technology is currently one of the most effective methods. However, conventional ventilation-based drag reduction methods often result in bubble trails at the tail, easily revealing the vehicle's location. High-temperature steam drag reduction, on the other hand, involves spraying high-temperature steam onto the surface of the vehicle to form a gas-liquid mixture covering it. This high-temperature steam condenses into water upon contact with the condenser, eliminating the need for venting at the tail and resolving the bubble trail issue that exposes the vehicle's position, thus increasing stealth. However, the condensation characteristics of high-temperature steam upon entering the water cause significant differences in the stability of the gas-liquid mixture and its drag reduction characteristics compared to conventional ventilation-based drag reduction using non-condensable gases. Therefore, high-temperature steam drag reduction experiments are needed to test the stability and drag reduction effects of the gas-liquid mixture under different ventilation methods and volumes, providing support for mastering the design technology of high-temperature steam drag reduction.

[0003] Using water tunnel testing to study the drag reduction characteristics of ventilation is an effective method. While current methods for measuring drag reduction using compressed air are available, there are fundamental differences compared to drag reduction measurements using high-temperature steam. Firstly, the gas properties differ: conventional compressed air testing does not require consideration of temperature changes, while high-temperature steam testing necessitates consideration of temperature variations and phase changes, placing higher demands on the gas source, delivery pipelines, and flow measurement in the ventilation system. Secondly, high-temperature steam testing requires consideration of the heat transfer effects on the test model, necessitating thermal insulation design. Furthermore, due to the large mass flow rate and high velocity of the high-temperature steam, the impact of steam impulse on the drag measurement results needs to be considered, requiring the elimination of interference through experimental and data processing methods. Moreover, there are currently no methods or devices for drag reduction testing using high-temperature steam, either domestically or internationally. Therefore, there is an urgent need to invent a test device and method for drag reduction using high-temperature steam film. Summary of the Invention

[0004] The present invention aims to solve at least one of the technical problems existing in the prior art.

[0005] According to one aspect of the present invention, a high-temperature steam film drag reduction measurement test device is provided. This device includes: a ventilation system, a test model, and a data acquisition system. The ventilation system and the data acquisition system are respectively connected to the test model, which is installed inside a water tunnel. The ventilation system includes a steam generator, a steam pressure reducing valve, a high-temperature resistant vortex flow meter, and a high-temperature resistant high-pressure steam pipe. The steam pressure reducing valve is connected to the steam generator and the high-temperature resistant vortex flow meter via the high-temperature resistant high-pressure steam pipe. The high-temperature vortex flow meter is connected to the test model via the high-temperature resistant high-pressure steam pipe. The steam generator provides high-temperature steam, the steam pressure reducing valve controls the ventilation flow rate, and the high-temperature vortex flow meter measures the ventilation volume. The data acquisition system includes a force balance, a data acquisition card, and a data acquisition computer. The force balance is located inside the test model and connected to the data acquisition card. The force balance measures the force on the test model during the test. The data acquisition card collects test data, and the data acquisition computer is connected to the data acquisition card and processes and stores the data.

[0006] Furthermore, the test model has a gas chamber and a heat insulation layer. A high-temperature and high-pressure steam pipe is connected to the gas chamber, and the heat insulation layer is located on the inner surface of the gas chamber. Both the gas chamber and the heat insulation layer have exhaust holes that communicate with the outside of the test model.

[0007] Furthermore, the high-temperature water vapor film drag reduction measurement test device also includes a belly support rod, and the test model is installed in the water tunnel by using the belly support rod in a belly support manner.

[0008] Furthermore, a high-temperature and high-pressure steam pipe connected to the test model is installed inside the abdominal support rod, and the force balance is fixedly connected to the abdominal support rod.

[0009] According to another aspect of the present invention, a method for measuring drag reduction of a high-temperature water vapor film is provided, wherein the drag reduction test is performed using the high-temperature water vapor film drag reduction test device described above.

[0010] Further, the high-temperature steam film drag reduction measurement test method includes: Step 1, designing the test model dimensions, selecting the design force balance range and the diameter of the high-temperature and high-pressure steam pipe; Step 2, connecting and installing the ventilation system, test model, and acquisition system; Step 3, adjusting the model mounting platform and correcting the test model's attitude to a zero-angle state; Step 4, adjusting the drag reduction measurement test device parameters, including the water tunnel flow velocity, the ventilation system's ventilation volume, and the acquisition system's sampling frequency; Step 5, starting the test, after the water tunnel flow velocity stabilizes, opening the steam pressure reducing valve until the airflow stabilizes, recording the model's resistance parameters before and after ventilation, completing one test condition; Step 6, checking the model's attitude position, confirming that the balance force parameters return to the state before ventilation after closing the ventilation, ensuring the model is in a zero-angle state, repeating the previous test condition, and then proceeding to the next set of conditions until all test conditions are completed; Step 7, measuring the resistance compensation caused by the steam impulse; Step 8, draining the water from the water tunnel, shutting down all systems, and completing the test.

[0011] Further, step one specifically includes: determining the maximum shell diameter of the test model based on the length of the water tunnel test section and the blockage ratio; estimating the model resistance and ventilation volume through numerical simulation, and selecting a force balance with a suitable range and a high-temperature and high-pressure steam pipe with a suitable diameter; and determining the minimum shell diameter of the test model based on the dimensions of the balance, abdominal support rod, and high-temperature and high-pressure steam pipe installed inside the test model shell.

[0012] Furthermore, step three specifically includes: 1) ensuring that the model is installed horizontally and the angle of attack is zero by measuring with a level or observing the water level; 2) ensuring that the side slip angle of the model is zero by starting the water tunnel to a certain flow rate and measuring the force with a balance.

[0013] Furthermore, step four specifically includes adjusting the inflow velocity Ui of the water tunnel, the hydrodynamic pressure Pi, the ventilation volume Qi of the ventilation system, and the sampling frequency of the acquisition system.

[0014] Further, step seven specifically includes: passing high-temperature water vapor through the water tunnel under the condition of zero flow velocity, measuring the model resistance data Fqi under different ventilation rates Qi, using it as the resistance compensation amount caused by the high-temperature water vapor impulse, and obtaining the resistance reduction amount for the corresponding ventilation rate condition as Fwi+Fqi-Fci, where Fwi and Fci are the model resistance parameters before and after ventilation, respectively.

[0015] This invention provides a high-temperature steam film drag reduction measurement test device and method. The device includes a ventilation system, a test model, and a data acquisition system. The ventilation system comprises a steam generator, a steam pressure reducing valve, a high-temperature vortex flow meter, and a high-temperature high-pressure steam pipe, providing controllable high-temperature steam to the test model to simulate drag reduction of an underwater vehicle. The data acquisition system measures the drag data of the test model. This invention features a simple structure and can simulate high-temperature steam drag reduction testing of an underwater vehicle in a water tunnel environment. Compared with existing technologies, this invention solves the technical problem of the inability to perform high-temperature steam film drag reduction tests in existing technologies. Attached Figure Description

[0016] The accompanying drawings, which form part of this specification, are provided to further illustrate embodiments of the invention and, together with the textual description, explain the principles of the invention. It is obvious that the drawings described below are merely some embodiments of the invention, and those skilled in the art can obtain other drawings based on these drawings without any creative effort.

[0017] Figure 1 A schematic diagram illustrating the working principle of the high-temperature water vapor film drag reduction measurement test device provided according to a specific embodiment of the present invention is shown.

[0018] Figure 2 A schematic diagram of the structure of the experimental model provided according to a specific embodiment of the present invention is shown;

[0019] Figure 3 A schematic diagram of the heat insulation layer and exhaust port structure of the air chamber provided according to a specific embodiment of the present invention is shown.

[0020] The above figures include the following reference numerals:

[0021] 10. Test model; 11. Gas chamber; 12. Insulation layer; 10a. Exhaust vent; 20. Abdominal support rod; 30. High temperature and high pressure resistant steam pipe; 40. Force balance. Detailed Implementation

[0022] It should be noted that, unless otherwise specified, the embodiments and features described in this application can be combined with each other. 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 a part of the embodiments of the present invention, and not all of them. The following description of at least one exemplary embodiment is merely illustrative and is in no way intended to limit the present invention or its application or use. 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.

[0023] It should be noted that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the exemplary embodiments according to this application. As used herein, the singular form is intended to include the plural form as well, unless the context clearly indicates otherwise. Furthermore, it should be understood that when the terms "comprising" and / or "including" are used in this specification, they indicate the presence of features, steps, operations, devices, components, and / or combinations thereof.

[0024] Unless otherwise specifically stated, the relative arrangement, numerical expressions, and values ​​of the components and steps set forth in these embodiments do not limit the scope of the invention. It should also be understood that, for ease of description, the dimensions of the various parts shown in the drawings are not drawn to actual scale. Techniques, methods, and devices known to those skilled in the art may not be discussed in detail, but where appropriate, such techniques, methods, and devices should be considered part of the specification. In all examples shown and discussed herein, any specific values ​​should be interpreted as merely exemplary and not as limitations. Therefore, other examples of exemplary embodiments may have different values. It should be noted that similar reference numerals and letters in the following figures denote similar items; therefore, once an item is defined in one figure, it need not be further discussed in subsequent figures.

[0025] like Figures 1 to 3As shown in the figure, a high-temperature steam film drag reduction measurement test device is provided according to a specific embodiment of the present invention. The high-temperature steam film drag reduction measurement test device includes: a ventilation system, a test model, and a data acquisition system. The ventilation system and the data acquisition system are respectively connected to the test model, which is installed inside a water tunnel. The ventilation system includes a steam generator, a steam pressure reducing valve, a high-temperature resistant vortex flow meter, and a high-temperature resistant high-pressure steam pipe. The steam pressure reducing valve is connected to the steam generator and the high-temperature resistant vortex flow meter through the high-temperature resistant high-pressure steam pipe. The high-temperature resistant vortex flow meter is connected to the test model through the high-temperature resistant high-pressure steam pipe. The steam generator is used to provide high-temperature steam, the steam pressure reducing valve is used to control the ventilation flow rate, and the high-temperature resistant vortex flow meter is used to measure the ventilation volume. The data acquisition system includes a force balance, a data acquisition card, and a data acquisition computer. The force balance is located inside the test model and is connected to the data acquisition card. The force balance is used to measure the force on the test model during the test. The data acquisition card is used to acquire test data, and the data acquisition computer is connected to the data acquisition card. The data acquisition computer is used to process and store the data.

[0026] This configuration provides a high-temperature steam film drag reduction measurement test device. The device includes a ventilation system, a test model, and a data acquisition system. The ventilation system comprises a steam generator, a steam pressure reducing valve, a high-temperature vortex flow meter, and a high-temperature high-pressure steam pipe, providing controllable high-temperature steam to the test model to simulate drag reduction of an underwater vehicle. The data acquisition system measures the drag data of the test model. This invention's high-temperature steam film drag reduction measurement test device has a simple structure and can simulate high-temperature steam drag reduction testing of underwater vehicles in a water tunnel testing environment. Compared with existing technologies, this invention solves the technical problem that existing technologies cannot achieve high-temperature steam film drag reduction testing.

[0027] Furthermore, in this invention, as Figure 2 and Figure 3 As shown, to prevent high-temperature water vapor from condensing before exiting the exhaust chamber 11, the test model 10 can be configured with an exhaust chamber 11 and a heat insulation layer 12. A high-temperature and high-pressure steam pipe 30 is connected to the exhaust chamber 11, and the heat insulation layer 12 is located on the inner surface of the exhaust chamber 11. Both the exhaust chamber 11 and the heat insulation layer 12 have exhaust holes 10a that communicate with the outside of the test model 10. The heat insulation layer 12, in conjunction with the high-temperature and high-pressure steam pipe 30, can prevent high-temperature water vapor from condensing before exiting the exhaust chamber 11, thus preventing the heat transfer of high-temperature steam from affecting the force balance 40 inside the model.

[0028] Furthermore, in this invention, to facilitate the installation of the test model 10, a high-temperature steam film drag reduction measurement test device can be configured, which also includes a belly support rod 20. The test model 10 is installed in the water tunnel using the belly support rod 20. As a specific embodiment of this invention, the test model 10 can be an underwater low-resistance model, and the high-temperature and high-pressure steam pipe 30 connected to the test model 10 can be installed inside the belly support rod 20. The force balance 40 can be fixedly connected to the belly support rod 20.

[0029] According to another aspect of the present invention, a method for measuring drag reduction in a high-temperature water vapor film is provided. This method employs the high-temperature water vapor film drag reduction measurement device described above to perform drag reduction testing. The method specifically includes:

[0030] Step 1: Design the dimensions of the test model, and select the range of the force balance and the diameter of the high-temperature and high-pressure steam pipe.

[0031] As a specific embodiment of the present invention, the maximum shell diameter of the test model can be determined according to the length of the water tunnel test section and the blockage ratio; the model resistance and ventilation volume can be estimated by numerical simulation, and a force balance with a suitable range and a high-temperature and high-pressure steam pipe with a suitable diameter can be selected; the minimum shell diameter of the test model can be determined according to the dimensions of the balance, abdominal support rod and high-temperature and high-pressure steam pipe installed inside the shell of the test model.

[0032] Step two: Connect and install the ventilation system, test model, and data acquisition system.

[0033] A force balance is installed inside the test model. One end of the force balance is fixed to the abdominal support rod. The test model is connected to the high-temperature vortex flow meter outside the water tunnel through the abdominal support rod. A high-temperature and high-pressure steam pipe ventilation line is laid inside the test model and connected to the high-temperature vortex flow meter.

[0034] Step 3: Adjust the model mounting platform to correct the test model's attitude to a zero-angle state.

[0035] When the abdominal support rod is assembled onto the water tunnel mounting platform, mechanical fine-tuning is used to ensure that the test model is installed with zero angle of attack and zero lateral slippage.

[0036] Step four: Adjust the parameters of the drag reduction measurement test device, including the inflow velocity of the water tunnel, the ventilation volume of the ventilation system, and the sampling frequency of the acquisition system.

[0037] Step 5: The experiment begins. After the water flow velocity in the tunnel stabilizes, open the steam pressure reducing valve until the airflow stabilizes. Record the model resistance parameters before and after ventilation to complete one test condition.

[0038] Step 6: Check the model's attitude and position, confirm that the balance force parameters have returned to the state before ventilation was turned off, ensure that the model is in a zero-angle state, repeat the previous test condition, and then carry out the next set of conditions until all test conditions are completed.

[0039] Step 7: Measure the resistance compensation caused by the steam impulse: Pass high-temperature steam through the water tunnel under the condition of zero flow velocity, and measure the model resistance data under different ventilation conditions, which will be used as the resistance compensation caused by the high-temperature steam impulse.

[0040] Step 8: Drain the water from the water tunnel, shut down all systems, and the test is complete.

[0041] The present invention provides a method for measuring drag reduction of underwater high-temperature water vapor film by introducing high-temperature water vapor into a water tunnel under the condition of zero flow velocity and measuring the model resistance data under different ventilation rates. This data serves as the resistance compensation amount caused by the high-temperature water vapor impulse, providing a means for underwater high-temperature water vapor film drag reduction test measurement.

[0042] To gain a further understanding of the present invention, the following description is provided in conjunction with... Figures 1 to 3 The present invention provides a detailed description of the experimental method for measuring drag reduction of high-temperature water vapor film.

[0043] like Figures 1 to 3 As shown in the figure, a method for measuring drag reduction of high-temperature water vapor film is provided according to a specific embodiment of the present invention, which specifically includes the following steps.

[0044] Step 1, as follows Figure 2 As shown, the dimensions of the SUBOFF external test model are designed as follows: 1) The maximum shell diameter D_max of the test model is determined based on the length of the water tunnel test section and the blockage ratio; 2) The model resistance F(N) and ventilation rate Q(m³) are estimated using numerical simulation. 3 / s), select a force balance with a range between 1.5F and 3F and an inner diameter not less than 3) Calculate the minimum test model shell diameter D_min = d1 + 2d2 + 20mm based on the balance diameter d1 installed inside the test model shell and the outer diameter d2 of the high temperature and high pressure steam pipe; 4) Select the test model shell diameter between D_min and D_max.

[0045] Step 2: Connect and install the ventilation system, test model, and data acquisition system: A force balance is installed inside the test model, with one end of the force balance fixed to the abdominal support rod. The test model is connected to the high-temperature vortex flow meter outside the water tunnel through the abdominal support rod. A high-temperature and high-pressure steam pipe ventilation line is laid inside the test model and connected to the high-temperature vortex flow meter.

[0046] Step 3: Adjust the model mounting platform to correct the model's attitude to a zero-angle state: When the abdominal support rod is assembled onto the water tunnel mounting platform, mechanical fine-tuning is used to ensure that the model is installed with zero angle of attack and zero sideslip. Specifically, 1) the model is installed horizontally with a zero angle of attack by measuring with a level or observing the water level line; 2) the water tunnel is started to a certain flow rate, and the force measured by the balance is zero, ensuring that the model's sideslip angle is zero.

[0047] Step 4: Adjust the parameters of the drag reduction measurement test device according to the test conditions: adjust the inflow velocity Ui of the water tunnel, the hydrodynamic pressure Pi, the ventilation volume Qi of the ventilation system, and the sampling frequency of the acquisition system.

[0048] Step 5: The experiment begins. After the water flow velocity in the tunnel stabilizes, open the high-temperature steam vent valve until the airflow stabilizes. Record the model resistance parameters Fwi and Fci before and after ventilation to complete one test condition.

[0049] Step 6: Check the model's attitude and position, confirm that the balance force parameters have returned to the state before ventilation was turned off, ensure that the model is in a zero-angle state, repeat the previous working condition, and then carry out the next set of working conditions until all test working conditions are completed.

[0050] Step 7: Measure the resistance compensation caused by the steam impulse. Pass high-temperature steam through the water tunnel under the condition of zero flow velocity and measure the model resistance data Fqi under different ventilation rates Qi. Use this data as the resistance compensation caused by the high-temperature steam impulse. The resistance reduction for the corresponding ventilation rate condition is obtained as Fwi + Fqi - Fci.

[0051] Step 8: Drain the water from the water tunnel, shut down all systems, and the test is complete.

[0052] In summary, this invention provides a high-temperature steam film drag reduction measurement test device and method. The device includes a ventilation system, a test model (10), and a data acquisition system. The ventilation system comprises a steam generator, a steam pressure reducing valve, a high-temperature vortex flow meter, and a high-temperature high-pressure steam pipe (30), providing controllable high-temperature steam to the test model (10) to simulate drag reduction of an underwater vehicle using high-temperature steam. The data acquisition system measures the drag data of the test model (10). The high-temperature steam film drag reduction measurement test device of this invention has a simple structure and can simulate high-temperature steam drag reduction testing of an underwater vehicle in a water tunnel test environment. Compared with the prior art, the technical solution of this invention can solve the technical problem that the prior art cannot achieve high-temperature steam film drag reduction testing.

[0053] For ease of description, spatial relative terms such as "above," "on top of," "on the upper surface of," "above," etc., are used herein to describe the spatial positional relationship of a device or feature as shown in the figures to other devices or features. It should be understood that spatial relative terms are intended to encompass different orientations in use or operation beyond the orientation of the device as described in the figures. For example, if the device in the figures were inverted, a device described as "above" or "on top of" other devices or structures would subsequently be positioned as "below" or "under" other devices or structures. Thus, the exemplary term "above" can include both "above" and "below." The device may also be positioned in other different ways (rotated 90 degrees or in other orientations), and the spatial relative descriptions used herein will be interpreted accordingly.

[0054] The above description is merely a preferred embodiment of the present invention and is not intended to limit the invention. Various modifications and variations can be made to the present invention by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A high temperature water vapor skin friction drag measurement test apparatus, characterized by, The high-temperature water vapor gas film drag reduction measurement test device comprises an air supply system, a test model and a collection system, the air supply system and the collection system are connected with the test model respectively, and the test model is installed in a water tunnel; the air supply system comprises a steam generator, a steam pressure reducing valve, a high-temperature vortex flowmeter and a high-temperature high-pressure steam pipe, the steam pressure reducing valve is communicated with the steam generator and the high-temperature vortex flowmeter through the high-temperature high-pressure steam pipe, the high-temperature vortex flowmeter is communicated with the test model through the high-temperature high-pressure steam pipe, the steam generator is used for providing high-temperature water vapor, the steam pressure reducing valve is used for controlling the air supply flow, and the high-temperature vortex flowmeter is used for measuring the air supply amount; the collection system comprises a force measuring balance, a data collection card and a collection computer, the force measuring balance is located in the test model and connected with the data collection card, the force measuring balance is used for measuring the force of the test model in the test process, the data collection card is used for collecting test data, and the collection computer is connected with the data collection card and used for processing and storing data.

2. The high-temperature water vapor gas-membrane drag-reduction measurement test apparatus according to claim 1, characterized by The test model has an air chamber and a heat insulation layer, the high-temperature high-pressure steam pipe is communicated to the air chamber, and the heat insulation layer is located on the inner surface of the air chamber; the air chamber and the heat insulation layer both have exhaust holes communicated with the outside of the test model.

3. The high-temperature water vapor gas-membrane drag-reduction measurement test apparatus according to claim 1 or 2, characterized by The high-temperature water vapor gas film drag reduction measurement test device further comprises a belly support rod, and the test model is installed in the water tunnel in a belly support mode through the belly support rod.

4. The high-temperature water vapor gas-membrane drag-reduction measurement test apparatus according to claim 3, characterized by The high-temperature high-pressure steam pipe communicated with the test model is arranged in the belly support rod, and the force measuring balance is fixedly connected with the belly support rod.

5. A method for measuring a drag reduction effect of a gas film by high-temperature water vapor, characterized by, The high-temperature water vapor gas film drag reduction measurement test method is implemented by the high-temperature water vapor gas film drag reduction measurement test device of claim 3 or 4.

6. The high-temperature water vapor gas-membrane drag-reduction measurement test method according to claim 5, characterized by, The high-temperature water vapor gas film drag reduction measurement test method comprises the following steps: Step 1: designing the size of the test model, selecting the range of the force measuring balance and the diameter of the high-temperature high-pressure steam pipe; Step 2: connecting and installing the air supply system, the test model and the collection system; Step 3: adjusting the model installation table and correcting the posture of the test model to a zero angle state; Step 4: adjusting the parameters of the drag reduction measurement test device, including the water tunnel flow velocity, the air supply amount of the air supply system and the sampling frequency of the collection system; Step 5: starting the test, opening the steam pressure reducing valve after the water tunnel flow velocity is stable, recording the model drag parameters before and after air supply until the air flow is stable, and completing one test condition; Step 6: checking the posture position of the model, confirming that the force measuring parameter of the balance returns to the state before air supply after the air supply is closed, ensuring that the model is in a zero angle state, repeating the previous test condition, and then carrying out the next group of conditions until all test conditions are completed; Step 7: measuring the resistance compensation amount caused by the water vapor impulse; Step 8: discharging the water in the water tunnel, closing all systems, and completing the test.

7. The high-temperature water vapor gas-membrane drag-reduction measurement test method according to claim 6, characterized by, The step one specifically comprises: determining the maximum shell diameter of the test model according to the length of the water tunnel test section and the blockage ratio; estimating the model resistance and the ventilation volume by numerical simulation, selecting a force balance with a suitable range and a high-temperature and high-pressure steam pipe with a suitable pipe diameter; and determining the minimum shell diameter of the test model according to the sizes of the balance, the abdominal support rod and the high-temperature and high-pressure steam pipe installed inside the shell of the test model.

8. The high-temperature water vapor gas-membrane drag-reduction measurement test method according to claim 6, characterized by, The step three specifically comprises: 1) measuring or observing the water level line by using a level meter to ensure that the model is installed horizontally and the attack angle is zero; and 2) starting the water tunnel to a certain flow rate, and measuring the force of the balance to be zero to ensure that the side slip angle of the model is zero.

9. The high-temperature water vapor gas-membrane drag-reduction measurement test method according to claim 6, characterized by, The step four specifically comprises adjusting the water tunnel incoming flow velocity Ui, the hydrodynamic pressure Pi, the ventilation volume Qi of the ventilation system and the sampling frequency of the collection system.

10. The high-temperature water vapor gas-membrane drag-reduction measurement test method according to claim 6, characterized by, The step seven specifically comprises: under the condition that the flow rate in the water tunnel is zero, high-temperature water vapor is ventilated, the model resistance data Fqi under different ventilation volumes Qi are measured, the resistance compensation amount caused by the high-temperature water vapor impulse is obtained, and the resistance reduction amount corresponding to the ventilation condition is Fwi+Fqi-Fci, wherein Fwi and Fci are respectively the model resistance parameters before and after ventilation.

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