Rapid calibration device and method for fan flow

Abstract

The invention belongs to the technical field of airflow flow calibration, and particularly relates to a fan flow rapid calibration device and method, current thermal expansion and cold contraction conditions of a long-neck nozzle and an outflow pipe can be obtained by calculating the current inner diameter d of the long-neck nozzle and the inner diameter D of the outflow pipe in real time, and therefore the mass flow Q flowing through the long-neck nozzle can be accurately obtained; accurate flow calibration is carried out; meanwhile, a rectification grid is arranged on the upstream of the long-neck nozzle, gas flowing through the long-neck nozzle is rectified, and gas inlet uniformity and scene nozzle flow measurement accuracy are guaranteed; mass flow calculation is carried out by arranging a plurality of measuring points, the flow standard device does not need to be installed at an inlet of a marked equipment pipeline, multiple sets of calibration devices do not need to be installed either, cost is reduced, and meanwhile assembly and disassembly are convenient. The device can be selectively mounted at the inlet and outlet of the fan according to the structural characteristics of the marked fan, and the applicability is wide; the nozzle structure change caused by the measurement environment is considered, and the flow calibration precision is high.

Description

Technical Field

[0001] The present application belongs to the technical field of airflow flow calibration, and in particular relates to a device and method for rapid calibration of fan flow. Background Art

[0002] When using the low-speed blowing method to detect the flow area of ​​the high- and low-pressure turbine guide vanes of aircraft engines, the volumetric fan inside the measuring equipment is affected by factors such as atmospheric pressure, temperature and humidity, and equipment wear and aging, and its flow characteristics will change unpredictably. Therefore, calibration is required to ensure the measurement accuracy of the guide vane flow area. However, due to the fact that the fan to be calibrated is located inside the equipment, offline calibration has the following disadvantages: 1. The portable gas flow calibration method does not take into account the thermal expansion and contraction of the nozzle and the change in area caused by changes in the use environment, resulting in inaccurate flow measurement and low calibration accuracy; 2. There is no rectification before the flow nozzle in the portable gas flow calibration device, and uneven air intake can easily cause inaccurate nozzle flow measurement, which has high requirements for air intake conditions; 3. The portable gas flow calibration device needs to be installed at the pipeline inlet of the calibrated equipment. For the calibrated equipment involving multiple air inlets, multiple sets of calibration devices need to be installed, which is costly, or other upstream structures of the calibrated equipment need to be disassembled, which is cumbersome to use and has low applicability.

[0003] Therefore, it is necessary to adopt a fast and convenient in-situ calibration device and method. Summary of the invention

[0004] The purpose of this application is to provide a device and method for rapid calibration of fan flow, so as to solve the problems that the existing off-line calibration method is not consistent with the actual use environment, calibration after disassembly affects the use of the equipment, and repeated disassembly and assembly increase the cumbersomeness of equipment use.

[0005] The first aspect of the present application provides a device for rapid calibration of fan flow, comprising a long-neck nozzle, an outlet pipe, a rectifying grid, a pressure stabilizing section and a transition section; the inlet end of the transition section is connected to the outlet of the calibrated fan, and the outlet end is connected to the inlet end of the pressure stabilizing section; the outlet end of the pressure stabilizing section is coaxially connected to the outlet pipe; a long-neck nozzle is arranged on the inner side of the outlet pipe; a signal processor is electrically connected to the long-neck nozzle, the signal processor is electrically connected to a computer, and an atmospheric pressure gauge is also connected to the signal processor; a porous medium is arranged in the pressure stabilizing section; A wall static pressure hole is opened at the throat of the long-neck nozzle and upstream of the outlet pipe. A temperature sensor and a static pressure sensor are provided in the outlet pipe and the long-neck nozzle. The static pressure sensor is arranged in the wall static pressure hole. An outlet pipe temperature measuring point, a long-neck nozzle temperature measuring point, an outlet pipe static pressure measuring point and a long-neck nozzle static pressure measuring point are formed on the outlet pipe and the long-neck nozzle. A rectifying grid is arranged upstream of the long-neck nozzle, and the rectifying grid is fixedly connected to the outlet pipe. An intake air temperature and humidity sensor is installed on the upstream isoannular surface of the rectifying grid to form an intake air temperature and humidity measuring point.

[0006] The second aspect of the present application provides a method for rapid calibration of fan flow, comprising: Estimate the flow range of the calibrated fan, determine the calibration range, select a long-neck nozzle that meets the calibration range, select the outlet pipe according to the inner diameter d of the long-neck nozzle, select the rectifier grid and the voltage stabilizing section according to the inner diameter D of the outlet pipe, and select the transition section whose size matches the size of the voltage stabilizing section; Establish a calibration device: install the long-neck nozzle and the rectifying grid on the outlet pipe, and evenly distribute multiple static pressure measuring points on the upstream and downstream of the inlet end face of the long-neck nozzle; evenly embed multiple temperature measuring points on the throat of the long-neck nozzle and the circumference of the upstream outlet pipe; install multiple inlet temperature and humidity measuring points on the annular surface upstream of the rectifying grid, and install the atmospheric pressure gauge in the test environment; The static pressure Ps1 of the throat of the long-neck nozzle and the static pressure Ps0 of the upstream inflow of the long-neck nozzle are obtained through the static pressure measuring point, the real-time temperature T1 of the long-neck nozzle and the real-time temperature T2 of the outlet pipe wall are obtained through the temperature measuring point, the inflow temperature t and humidity Hu are obtained through the inlet temperature and humidity measuring point, and the atmospheric pressure Pa is obtained through the atmospheric pressure gauge; then the mass flow Q flowing through the long-neck nozzle is calculated by iteration according to the obtained data; Control the air supply of the calibrated fan, increase the speed to the calibration range, obtain the mass flow Q currently flowing through the long-neck nozzle in real time, and record the speed of the calibrated fan. The calibrated fan continues to increase the intake flow until the flow calibration of the required calibration range is completed; Remove the calibration device, complete data processing and output, and end the calibration work.

[0007] Preferably, the iterative calculation is specifically designed as follows: The incoming flow temperature t and humidity Hu are measured by the inlet temperature and humidity measurement points, and the incoming flow physical parameters are calculated in combination with the ambient atmospheric pressure Pa. The incoming flow physical parameters include the incoming flow density , Viscosity and isentropic index ; According to the real-time temperature T1 of the long-neck nozzle and the real-time temperature T2 of the outlet pipe wall, the inner diameter temperature function of the long-neck nozzle and the outlet pipe wall is calculated. , T=T1 or T2; then the inner diameter d of the long-neck nozzle and the inner diameter D of the outlet pipe are calculated in real time according to the inner diameter temperature function to obtain the pipe diameter ratio ; The static pressure Ps1 at the throat of the long-neck nozzle and the static pressure Ps0 of the upstream flow of the long-neck nozzle obtained by the static pressure measurement point are used to calculate the pressure difference. , pressure ratio ; According to the pipe diameter ratio Combined with the pressure ratio and isentropic index Calculate the expansion coefficient ; According to the expansion coefficient Calculation parameters , and set the initial value of the long-neck nozzle outflow coefficient; Let the Reynolds number calculation formula where n=1, is the discharge coefficient of the long-neck nozzle, is the Reynolds number; substitute the initial value of the long-neck nozzle discharge coefficient into the Reynolds number calculation formula to obtain the Reynolds number iteration value , and iterate the value according to the Reynolds number Reynolds number Conduct continuous iterations; Determining the Reynolds number Whether the convergence judgment formula is satisfied, if it is satisfied, the mass flow calculation formula Output mass flow rate Q; if not satisfied, the nozzle discharge coefficient empirical formula Calculate the outflow coefficient iteration value , and continue iterating on the Reynolds number.

[0008] Preferably, the convergence judgment formula is , m is a positive integer set by the user; the initial value of the long-neck nozzle outflow coefficient is .

[0009] Preferably, the inner diameter D of the outlet pipe is 2d to 2.5d; the length of the rectifying grid is 2D to 2.5D, and the diameter of the voltage stabilizing section is 4D to 5D.

[0010] Preferably, a plurality of static pressure measuring points are evenly distributed circumferentially at a position 1D upstream of the inlet end face of the long-neck nozzle, and a plurality of static pressure measuring points are evenly distributed circumferentially at a position 0.5D downstream of the inlet end face of the long-neck nozzle.

[0011] The fan flow rapid calibration device and method of the present application can obtain the current thermal expansion and contraction of the long-neck nozzle and the outlet pipe by calculating the current long-neck nozzle inner diameter d and the outlet pipe inner diameter D in real time, so as to accurately obtain the mass flow Q flowing through the long-neck nozzle for accurate flow calibration; at the same time, by setting a rectifying grid upstream of the long-neck nozzle, the gas flowing through the long-neck nozzle is rectified to ensure the uniformity of air intake and the accuracy of scene nozzle flow measurement; by setting multiple measuring points for mass flow calculation, the flow standard device does not need to be installed at the pipeline inlet of the calibrated equipment, nor does it need to install multiple sets of calibration devices, which reduces costs and is easy to install and disassemble. BRIEF DESCRIPTION OF THE DRAWINGS

[0012] In order to more clearly illustrate the technical solution provided by the present application, the following is a brief introduction to the accompanying drawings. Obviously, the accompanying drawings described below are only some embodiments of the present application.

[0013] Figure 1 This is a schematic diagram of the overall structure of the rapid calibration device for this application; Figure 2 This is a schematic diagram of the overall process of the rapid calibration method for this application.

[0014] 1. The outlet of the marked fan; 2. The transition section; 3. The pressure stabilizing section; 4. The porous medium; 5. The atmospheric pressure gauge; 6. The signal processor; 7. The computer; 8. The outlet pipe; 9. The temperature measuring point of the long-neck nozzle; 10. The static pressure measuring point of the long-neck nozzle; 11. The long-neck nozzle; 12. The temperature measuring point of the outlet pipe; 13. The static pressure measuring point of the outlet pipe; 14. The rectifier grille; 15. The measuring points of the inlet temperature and humidity. DETAILED DESCRIPTION

[0015] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0016] The first aspect of the present application provides a device for rapid calibration of fan flow, such as Figure 1, including a long-neck nozzle 11, an outlet pipe 8, a rectifying grid 14, a pressure stabilizing section 3 and a transition section 2. The inlet end of the transition section 2 is connected to the marked fan outlet 1, and the outlet end is connected to the inlet end of the pressure stabilizing section 3; the outlet end of the pressure stabilizing section 3 is coaxially connected to the outlet pipe 8. A long-neck nozzle 11 is arranged on the inner side of the outlet pipe 8; the long-neck nozzle 11 is electrically connected to a signal processor 6, the signal processor 6 is electrically connected to a computer 7, and the signal processor 6 is also connected to an atmospheric pressure gauge 5.

[0017] The pressure stabilizing section 3 is provided with a porous medium 4, which can reduce the spatial non-uniformity of the incoming flow velocity and reduce the pressure; the throat of the long-neck nozzle 11 and the upstream of the outlet pipe 8 are provided with a wall static pressure hole, and the outlet pipe 8 and the long-neck nozzle 11 are provided with a temperature sensor and a static pressure sensor, and the static pressure sensor is arranged in the wall static pressure hole, and the outlet pipe temperature measuring point 12, the long-neck nozzle temperature measuring point 9, the outlet pipe static pressure measuring point 13 and the long-neck nozzle static pressure measuring point 10 are formed on the outlet pipe 8 and the long-neck nozzle 11. The corresponding temperature measuring point is used to obtain the real-time temperature of the long-neck nozzle 11 and the outlet pipe 8, and to correct the inner diameter of the long-neck nozzle 11 and the outlet pipe 8; the corresponding static pressure measuring point is connected to the signal processor 6 and the computer 7, and the local static pressure value is output in real time.

[0018] A rectifying grid 14 is also provided upstream of the long-neck nozzle 11. The rectifying grid 14 is fixedly connected to the outlet pipe 8 to play a rectifying and vortex-breaking role, so that the flow of the outlet pipe 8 is uniform and stable during calibration. An intake temperature and humidity sensor is installed on the upstream annular surface of the rectifying grid 14 to form an intake temperature and humidity measuring point 15 for measuring the temperature and humidity conditions of the incoming flow and calculating the physical property parameters of the incoming flow.

[0019] The transition section 2 is installed or not depending on whether the calibration device is connected to the outlet 1 of the calibrated fan, and is detachably connected to the upstream of the pressure stabilizing section 3. The transition section 2 is connected to the outlet 1 of the calibrated fan to form a calibration flow pipeline with good air tightness.

[0020] The second aspect of the present application provides a method for rapid calibration of fan flow, using the above calibration device to perform rapid calibration of fan flow, such as Figure 2 , specifically including the following steps: Step S100, structure selection: estimate the flow range of the calibrated fan, determine the calibration range, select a long-neck nozzle that meets the calibration range, select an outlet pipe according to the inner diameter of the long-neck nozzle, select a rectifier grid and a voltage stabilizing section according to the inner diameter of the outlet pipe, and select a transition section whose size matches the size of the voltage stabilizing section.

[0021] Preferably, the inner diameter of the long-neck nozzle is d, the inner diameter D of the outlet pipe is 2d to 2.5d; the length of the rectifying grid is 2D to 2.5D, and the diameter of the voltage stabilizing section is 4D to 5D.

[0022] Step S200, calibration device installation: install the long-neck nozzle and the rectifying grid on the outlet pipe. The specific installation method is to determine whether the vortex size of the long-neck nozzle inlet surface is smaller than the set value or there is no vortex in the flow state of the upstream when the air is inlet at the current installation position. If the vortex size is larger than the set value, adjust the installation position of the long-neck nozzle and the rectifying grid again until the requirements are met.

[0023] Multiple static pressure measuring points are evenly distributed around the upstream and downstream of the inlet end face of the long-neck nozzle. Multiple temperature measuring points are evenly embedded around the throat of the long-neck nozzle and the upstream outlet pipe. Multiple inlet temperature and humidity measuring points are installed on the annular surface upstream of the rectifier grid, and the atmospheric pressure gauge is installed in the test environment.

[0024] If the calibration device needs to be installed at the outlet of the fan to be calibrated, connect the calibration device together with the transition section to the outlet of the fan to be calibrated; otherwise, do not install the transition section.

[0025] Assemble and connect the above hardware to ensure that the flow pipeline is airtight and the sensors at each measuring point work normally.

[0026] Preferably, a plurality of static pressure measuring points are evenly distributed circumferentially at a position 1D upstream of the inlet end face of the long-neck nozzle, and a plurality of static pressure measuring points are evenly distributed circumferentially at a position 0.5D downstream of the inlet end face of the long-neck nozzle.

[0027] Step S300, mass flow calculation: obtain the long-neck nozzle throat static pressure Ps1 and the long-neck nozzle upstream incoming flow static pressure Ps0 through the static pressure measuring point, obtain the long-neck nozzle real-time temperature T1 and the outlet pipe wall real-time temperature T2 through the temperature measuring point, obtain the incoming flow temperature t and humidity Hu through the inlet temperature and humidity measuring point, and obtain the atmospheric pressure Pa through the atmospheric pressure gauge; then calculate the mass flow Q flowing through the long-neck nozzle in an iterative manner based on the obtained data; The specific design of iterative calculation is as follows: Step S310, measuring the incoming flow temperature t and humidity Hu through the inlet temperature and humidity measurement point, and calculating the incoming flow physical parameters in combination with the ambient atmospheric pressure Pa. The incoming flow physical parameters include the incoming flow density , Viscosity , isentropic index wait; Step S320, according to the real-time temperature T1 of the long-neck nozzle and the real-time temperature T2 of the outlet pipe wall, calculate the inner diameter temperature function of the long-neck nozzle and the outlet pipe wall , T=T1 or T2; then the inner diameter d of the long-neck nozzle and the inner diameter D of the outlet pipe are calculated in real time according to the inner diameter temperature function to obtain the pipe diameter ratio ; Step S330, calculate the pressure difference based on the static pressure Ps1 of the throat of the long-neck nozzle and the static pressure Ps0 of the upstream flow of the long-neck nozzle obtained by the static pressure measurement point , pressure ratio ; Step S340, according to the pipe diameter ratio Combined with the pressure ratio and isentropic index Calculate the expansion coefficient ; Just use the existing formula to calculate.

[0028] Step S350, according to the expandability coefficient Calculation parameters , set the initial value of the long neck nozzle outflow coefficient to ; Step S360, let the Reynolds number calculation formula where n=1, is the discharge coefficient of the long-neck nozzle, is the Reynolds number; substitute the initial value of the long-neck nozzle discharge coefficient into the Reynolds number calculation formula to obtain the Reynolds number iteration value , and iterate the value according to the Reynolds number Reynolds number Conduct continuous iterations; Step S370, determining the Reynolds number Whether the convergence judgment formula is satisfied , m is a positive integer set by the user; if it satisfies, the mass flow calculation formula Output mass flow rate Q; if not satisfied, the nozzle discharge coefficient empirical formula Calculate the outflow coefficient iteration value , and continue iterating on the Reynolds number.

[0029] Step S400, flow calibration: control the air supply of the calibrated fan, slowly increase the speed to the calibration range, obtain the mass flow Q currently flowing through the long-neck nozzle in real time, and record the speed of the calibrated fan. The calibrated fan continues to increase the intake flow until the flow calibration of the required calibration range is completed. If the calibration range exceeds the working range of a group of long-neck nozzles, multiple groups of long-neck nozzles are collected to complete the calibration work.

[0030] Step S500, completing calibration: removing the calibration device, completing data processing and output, and ending the calibration work.

[0031] Through the above design, by real-time calculation of the current long-neck nozzle inner diameter d and the outlet pipe inner diameter D, the current thermal expansion and contraction of the long-neck nozzle and the outlet pipe can be obtained, so that the mass flow rate Q flowing through the long-neck nozzle can be accurately obtained for accurate flow calibration; at the same time, by setting a rectifying grid upstream of the long-neck nozzle, the gas flowing through the long-neck nozzle is rectified to ensure the uniformity of air intake and the accuracy of scene nozzle flow measurement; by setting multiple measuring points for mass flow calculation, the flow standard device does not need to be installed at the pipeline inlet of the calibrated equipment, nor does it need to install multiple sets of calibration devices, which reduces costs and is easy to install and disassemble.

[0032] Finally, it should be noted that: the drawings of the embodiments disclosed in the present invention only involve structures related to the embodiments disclosed in the present invention, and other structures can refer to the general design. In the absence of conflict, the same embodiment and different embodiments of the present invention can be combined with each other; Finally: The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A fan flow rapid calibration device, characterized in that: The invention comprises a long-neck nozzle (11), an outlet pipe (8), a rectifying grid (14), a pressure stabilizing section (3) and a transition section (2); the inlet end of the transition section (2) is connected to the outlet (1) of the marked fan, and the outlet end is connected to the inlet end of the pressure stabilizing section (3); the outlet end of the pressure stabilizing section (3) is coaxially connected to the outlet pipe (8); a long-neck nozzle (11) is arranged on the inner side of the outlet pipe (8); the long-neck nozzle (11) is electrically connected to a signal processor (6), the signal processor (6) is electrically connected to a computer (7), and the signal processor (6) is also connected to an atmospheric pressure gauge (5); a porous medium (4) is arranged in the pressure stabilizing section (3); the long-neck nozzle (11) is electrically connected to a signal processor (6), the signal processor (6) is electrically connected to a computer (7), and an atmospheric pressure gauge (5) is also connected to the signal processor (6); a porous medium (4) is arranged in the pressure stabilizing section (3); the long-neck nozzle (11) is electrically connected to a signal processor (6), and the signal processor (6) is electrically connected to a computer (7). ) is provided with a wall static pressure hole at the throat of the outlet pipe (8) and upstream of the outlet pipe (8); a temperature sensor and a static pressure sensor are provided in the outlet pipe (8) and the long-neck nozzle (11); the static pressure sensor is provided in the wall static pressure hole; an outlet pipe temperature measuring point (12), a long-neck nozzle temperature measuring point (9), an outlet pipe static pressure measuring point (13) and a long-neck nozzle static pressure measuring point (10) are formed on the outlet pipe (8) and the long-neck nozzle (11); a rectifying grid (14) is provided upstream of the long-neck nozzle (11); the rectifying grid (14) is fixedly connected to the outlet pipe (8); an intake air temperature and humidity sensor is installed on the upstream isocyclic surface of the rectifying grid (14) to form an intake air temperature and humidity measuring point (15).

2. A method for rapid calibration of fan flow, using the calibration device according to claim 1, characterized in that: include: Estimate the flow range of the calibrated fan, determine the calibration range, select a long-neck nozzle that meets the calibration range, select the outlet pipe according to the inner diameter d of the long-neck nozzle, select the rectifier grid and the voltage stabilizing section according to the inner diameter D of the outlet pipe, and select the transition section whose size matches the size of the voltage stabilizing section; Establish a calibration device: install the long-neck nozzle and the rectifying grid on the outlet pipe, and evenly distribute multiple static pressure measuring points on the upstream and downstream of the inlet end face of the long-neck nozzle; evenly embed multiple temperature measuring points on the throat of the long-neck nozzle and the circumference of the upstream outlet pipe; install multiple inlet temperature and humidity measuring points on the annular surface upstream of the rectifying grid, and install the atmospheric pressure gauge in the test environment; The static pressure Ps1 of the throat of the long-neck nozzle and the static pressure Ps0 of the upstream inflow of the long-neck nozzle are obtained through the static pressure measuring point, the real-time temperature T1 of the long-neck nozzle and the real-time temperature T2 of the outlet pipe wall are obtained through the temperature measuring point, the inflow temperature t and humidity Hu are obtained through the inlet temperature and humidity measuring point, and the atmospheric pressure Pa is obtained through the atmospheric pressure gauge; then the mass flow Q flowing through the long-neck nozzle is calculated by iteration according to the obtained data; Control the air supply of the calibrated fan, increase the speed to the calibration range, obtain the mass flow Q currently flowing through the long-neck nozzle in real time, and record the speed of the calibrated fan. The calibrated fan continues to increase the intake flow until the flow calibration of the required calibration range is completed; Remove the calibration device, complete data processing and output, and end the calibration work.

3. The method for rapid calibration of fan flow rate according to claim 2, characterized in that: The specific design of the iterative calculation is as follows: The incoming flow temperature t and humidity Hu are measured by the inlet temperature and humidity measurement points, and the incoming flow physical parameters are calculated in combination with the ambient atmospheric pressure Pa. The incoming flow physical parameters include the incoming flow density , Viscosity and isentropic index ; According to the real-time temperature T1 of the long-neck nozzle and the real-time temperature T2 of the outlet pipe wall, the inner diameter temperature function of the long-neck nozzle and the outlet pipe wall is calculated. , T=T1 or T2; then the inner diameter d of the long-neck nozzle and the inner diameter D of the outlet pipe are calculated in real time according to the inner diameter temperature function to obtain the pipe diameter ratio ; The static pressure Ps1 at the throat of the long-neck nozzle and the static pressure Ps0 of the upstream flow of the long-neck nozzle obtained by the static pressure measurement point are used to calculate the pressure difference. , pressure ratio ; According to the pipe diameter ratio Combined with the pressure ratio and isentropic index Calculate the expansion coefficient ; According to the expansion coefficient Calculation parameters , and set the initial value of the long-neck nozzle outflow coefficient; Let the Reynolds number calculation formula where n=1, is the discharge coefficient of the long-neck nozzle, is the Reynolds number; substitute the initial value of the long-neck nozzle discharge coefficient into the Reynolds number calculation formula to obtain the Reynolds number iteration value , and iterate the value according to the Reynolds number Reynolds number Conduct continuous iterations; Determining the Reynolds number Whether the convergence judgment formula is satisfied, if it is satisfied, the mass flow calculation formula Output mass flow rate Q; if not satisfied, the nozzle discharge coefficient empirical formula Calculate the outflow coefficient iteration value , and continue iterating on the Reynolds number.

4. The method for rapid calibration of fan flow rate according to claim 3, characterized in that: The convergence judgment formula is: , m is a positive integer set by the user; the initial value of the long-neck nozzle outflow coefficient is .

5. The method for rapid calibration of fan flow rate according to claim 2, characterized in that: The inner diameter D of the outlet pipe is 2d to 2.5d; the length of the rectifying grid is 2D to 2.5D, and the diameter of the voltage stabilizing section is 4D to 5D.

6. The method for rapid calibration of fan flow rate according to claim 2, characterized in that: A plurality of static pressure measuring points are evenly distributed circumferentially at a position 1D upstream of the inlet end face of the long-neck nozzle, and a plurality of static pressure measuring points are evenly distributed circumferentially at a position 0.5D downstream of the inlet end face of the long-neck nozzle.

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