Fresh air fan simulated pressure difference air volume test bench

Abstract

The present invention provides a new air blower simulated pressure difference air volume test bench, which relates to the field of air purification technology, including a ventilation duct, a front static pressure ring and a rear static pressure ring are provided on the ventilation duct, a wind resistance regulating valve is provided between the front static pressure ring and the rear static pressure ring, and an air volume tester is provided on the ventilation duct located on the side of the rear static pressure ring away from the front static pressure ring; one end of the ventilation duct close to the front static pressure ring is used to connect with the air outlet of the new air blower, and one end of the ventilation duct close to the rear static pressure ring is used to connect with the air inlet of the new air blower. The present invention adjusts the air volume and controls the wind resistance by setting a wind resistance regulating valve, and sets a front static pressure ring and a rear static pressure ring on both sides of the wind resistance regulating valve to display the wind resistance in real time, which can quickly and effectively test the air volume, and can simulate the filter resistance and test the simulated pressure difference at the same time, and the test is convenient.

Description

Technical Field

[0001] The invention relates to the technical field of air purification, and in particular to a new air blower simulated pressure difference air volume test bench. Background Art

[0002] The fresh air system is an independent air treatment system consisting of a ventilation fan, pipes and some accessories that can ventilate and purify the air. The ventilation fan filters and purifies the fresh air from outdoor, transports it into the room through pipes, and discharges the polluted air from indoor to outdoor.

[0003] The air supply and exhaust volume of the fresh air system are directly related to the indoor air circulation, and the air volume is mainly affected by the following factors: (1) the air volume provided by the motor fan itself; (2) the wind resistance of the purification system; (3) the wind resistance of the ventilation duct. From the above factors, it can be seen that the lower the resistance of the purification system and the ventilation duct, the higher the air volume provided by the fresh air system. Under normal circumstances, the resistance of the ventilation duct will not change much during use; but the wind resistance of the purification system will continue to increase with the increase of dust load on the purification system, and the exhaust volume of the fresh air fan that can be provided by the fresh air fan will gradually decrease.

[0004] Generally, motor fans will have a set of wind pressure-air volume curves for designers to use as a design reference. Designers design products based on the wind pressure-air volume curves of the motor fans, determine the initial and final wind resistance of the purification system, and leave a certain wind resistance margin for the ventilation ducts.

[0005] The purification system of the fresh air system is mainly composed of primary, medium and high efficiency filters. The wind resistance of each filter needs to be tested through a standard test air duct, and then installed in the fresh air fan for the air volume test of the whole machine. If the air volume does not meet the requirements, the filter or a fan with higher horsepower needs to be remade and then matched. In order to achieve the ideal air volume, multiple matches are often required, which has a long R&D cycle and high R&D costs. At the same time, previous wind speed tests mostly used anemometers to test the wind speed at the air outlet. Due to the uneven wind speed at the air outlet, the test results also have a large deviation. Therefore, it is necessary to develop a test bench that can quickly and effectively test the air volume, simulate the filter resistance and test the simulated pressure difference. Summary of the invention

[0006] The purpose of the present invention is to provide a new air fan simulated pressure difference air volume test bench, which adjusts the air volume and controls the wind resistance by setting a wind resistance regulating valve, and sets a front static pressure ring and a rear static pressure ring on both sides of the wind resistance regulating valve to display the wind resistance in real time. It can quickly and effectively test the air volume, simulate the filter resistance and test the simulated pressure difference, and the test is convenient.

[0007] The above technical objectives of the present invention are achieved through the following technical solutions:

[0008] A new air fan simulated pressure difference air volume test bench comprises a ventilation duct, wherein the ventilation duct is provided with a front end static pressure ring and a rear end static pressure ring, a wind resistance regulating valve is provided between the front end static pressure ring and the rear end static pressure ring, and the ventilation duct is provided with an air volume tester located on the side of the rear end static pressure ring away from the front end static pressure ring; an end of the ventilation duct close to the front end static pressure ring is used to be connected to the air outlet of the new air fan, and an end of the ventilation duct close to the rear end static pressure ring is used to be connected to the air inlet of the new air fan.

[0009] By adopting the above technical solution, the fresh air fan generally includes four air inlets and outlets, namely, outdoor fresh air inlet, indoor fresh air outlet, indoor return air inlet and outdoor return air outlet. Therefore, the fresh air fan simulated pressure difference air volume test bench needs to be applicable to four air inlets and outlets at the same time. Therefore, one end of the ventilation duct close to the front static pressure ring is connected to the air outlet of the fresh air fan, and one end of the ventilation duct close to the rear static pressure ring is connected to the air inlet of the fresh air fan to meet the usage requirements.

[0010] The fresh air blower can be equipped with a filter or not according to the test purpose. The wind enters the ventilation duct from the end of the ventilation duct close to the front static pressure ring. The static pressure difference between the front static pressure ring and the rear static pressure ring is the adjusted simulated wind resistance. The wind resistance regulating valve is used to adjust the size of the vent area to adjust the wind pressure and air volume. The air volume tester calculates the air volume. When in use, the wind resistance regulating valve is adjusted so that the wind resistance of the entire system reaches the design parameters, and the real-time air volume can be read out through the air volume tester. If multiple wind resistances need to be tested, you only need to adjust the wind resistance regulating valve to adjust the wind resistance to simulate the filter pressure difference. The test is convenient and easy to operate.

[0011] During the development phase of the new fan, there is no need to install a filter element in the new fan prototype. The pressure-air volume curve of the entire new fan system can be tested to provide design parameters for the new fan designers, which is convenient for designers to select fans and optimize air ducts. During the installation phase of the new fan, the entire set of new fans is tested to simulate the resistance of the air duct and test the wind resistance under different pressure differences, providing design parameters for the air duct. At the same time, the motor fan can also be directly tested to simulate different wind resistances and quickly draw the wind resistance curve of the motor fan.

[0012] The fresh air fan simulated pressure difference air volume test bench provided by the present invention simulates the pressure difference of the filter and the air duct by adjusting the wind resistance regulating valve, can adjust the pressure difference at will according to the requirements, and read the air volume in real time, has a simple structure, is easy to operate, and has a wide range of applications.

[0013] Furthermore, an airflow rectifier is provided between the wind resistance regulating valve and the rear static pressure ring, and the wind resistance regulating valve is arranged on the end face of the airflow rectifier; the airflow rectifier is a perforated plate structure including a plurality of rectifying holes, and the axial direction of the rectifying holes is parallel to the axial direction of the ventilation duct.

[0014] By adopting the above technical solution, an airflow rectifier is set, and a number of rectifying holes on the airflow rectifier are used to convert the irregular airflow at the front end into a regular airflow, thereby ensuring the accuracy of the wind pressure tested by the front static pressure ring and the rear static pressure ring, thereby ensuring the accuracy of the test results.

[0015] Furthermore, a thermometer and hygrometer is also provided on the ventilation duct, and the thermometer and hygrometer is located on a side of the air volume tester away from the rear static pressure ring.

[0016] By adopting the above technical solution, the thermometer and hygrometer are used to monitor the temperature and humidity of the test environment to avoid the influence of the test results on the air viscosity changes caused by different temperature and humidity. The thermometer and hygrometer feedbacks the temperature and humidity of the test environment in real time, which is convenient for adjusting the test environment and ensuring the consistency of the test. It has a simple structure and obvious effect.

[0017] Furthermore, the test temperature of the thermometer and hygrometer is 23±5°C, and the relative humidity is 50±20%.

[0018] By adopting the above technical solution, the test temperature is limited to 23±5°C and the relative humidity is limited to 50±20%, which can avoid the influence of changes in air viscosity caused by different temperatures and humidities on the test results and ensure the consistency of the test.

[0019] Furthermore, both ends of the ventilation duct are detachably connected with reducer adapters, and the diameter reduction angle of the reducer adapters is ≤15°.

[0020] By adopting the above technical solution, when the air inlet and outlet of the fresh air blower do not match the ventilation duct, the reducer quasi-joint can be used to achieve the connection between the ventilation duct and the air inlet and outlet of the fresh air blower, thereby improving the scope of application of the present invention. The reducer angle of the reducer adapter should be ≤15° to avoid the influence of the reducer adapter on the wind resistance when the reducer adapter changes its diameter, and ensure the accuracy of the wind pressure measurement by the front static pressure ring and the rear static pressure ring, that is, to ensure the accuracy of the simulated wind resistance.

[0021] Furthermore, the front static pressure ring and the rear static pressure ring have the same structure, both comprising four static pressure holes connected to the ventilation duct arranged in a circumferential array on the side wall of the ventilation duct, each group of four static pressure holes are connected through a hose, and the hose is connected to a pressure gauge.

[0022] By adopting the above technical scheme, a static pressure ring is formed by a static pressure hole, a hose and a pressure gauge to realize the test of static pressure, and the static pressure stability during the test is guaranteed, thereby ensuring the accuracy of the simulated wind resistance and improving the accuracy of the test results of the test bench. It has a simple structure and obvious effect.

[0023] Furthermore, an air guide tube arranged axially along the static pressure hole is connected to the static pressure hole on the ventilation duct, a ball head is provided at one end of the air guide tube away from the static pressure hole, and a soft hole cooperating with the ball head is provided on the hose.

[0024] By adopting the above technical solution, the ball head on the air duct is inserted into the soft hole on the hose, so that the hose and the static pressure hole can be connected. This makes it convenient to replace the hose when it is damaged. The cooperation between the ball head and the soft hole can ensure the sealing of the connection between the air duct and the hose, thereby ensuring the accuracy of the static pressure test structure.

[0025] Furthermore, the diameter of the ventilation duct is D, the distance between the front static pressure ring and the ventilation duct and one end port close to it is L1, and L1>4D.

[0026] By adopting the above technical solution, the distance L1 between the front static pressure ring and the air inlet end of the ventilation duct is greater than 4D, which avoids turbulence and causes inaccurate wind pressure tested by the front static pressure ring, thereby causing inaccurate simulated wind resistance and tested air volume.

[0027] Furthermore, the distance between one end of the airflow rectifier close to the air volume tester and the air volume tester is L2, and L2>4D.

[0028] By adopting the above technical solution, the distance L2 between the airflow rectifier and the air volume tester is greater than 4D, ensuring that the static pressure difference after rectification by the airflow rectifier has as little influence on the Pitot tube in the air volume tester when measuring the wind pressure as possible, thereby ensuring the accuracy of the air volume measured by the air volume tester.

[0029] Furthermore, the distance between the air volume tester and the ventilation duct and one end port close to it is L3, and L3>4D.

[0030] By adopting the above technical solution, the distance L3 between the air volume tester and the air outlet end of the ventilation duct is greater than 4D, thereby avoiding the influence of the turbulent flow at the air outlet on the air volume tester and ensuring the accuracy of the air volume measured by the air volume tester.

[0031] In summary, the present invention has the following beneficial effects:

[0032] 1. By setting a wind resistance regulating valve, and setting a front static pressure ring and a rear static pressure ring on both sides of the wind resistance regulating valve, the wind pressure and air volume are adjusted by the wind resistance regulating valve to simulate the pressure difference between the filter and the air duct. The pressure difference can be adjusted at will according to the requirements, and the simulated wind resistance and air volume can be output in real time, which is convenient for testing;

[0033] 2. During the development stage of the new air fan, there is no need to install a filter element in the new air fan prototype. The pressure-air volume curve of the entire new air fan system can be tested to provide design parameters for the new air fan designers, making it easier for them to select the fan and optimize the air duct.

[0034] 3. During the installation phase of the new fan, the whole set of new fan is tested to simulate the resistance of the air duct and test the wind resistance under different pressure differences to provide design parameters for the air duct;

[0035] 4. This new fan can also be directly connected to the air outlet of the corresponding motor fan to simulate different wind resistances and quickly draw the wind resistance curve of the corresponding motor fan. BRIEF DESCRIPTION OF THE DRAWINGS

[0036] Figure 1 This is the overall structural diagram of the new fan simulated pressure difference air volume test bench;

[0037] Figure 2 This is a schematic diagram of the installation structure when the fresh air fan simulated pressure difference air volume test bench tests the fresh air fan outlet;

[0038] Figure 3 This is a schematic diagram of the installation structure of the fresh air fan simulated pressure difference air volume test bench when testing the fresh air fan air inlet;

[0039] Figure 4 This is a schematic diagram of the structure of the front static pressure ring and the rear static pressure ring in the new fan simulated pressure difference air volume test bench;

[0040] Figure 5 This is a structural diagram of the wind resistance regulating valve in the new air blower simulated pressure difference air volume test bench;

[0041] Figure 6 It is a structural schematic diagram of the airflow rectifier in the new air fan simulated pressure difference air volume test bench.

[0042] In the figure, 1. fresh air fan; 2. ventilation duct; 21. reducer; 22. static pressure hole; 23. air guide pipe; 24. ball head; 3. front static pressure ring; 31. hose; 32. soft hole; 33. pressure gauge; 4. wind resistance regulating valve; 5. air flow rectifier; 51. rectifier hole; 6. rear static pressure ring; 7. air volume tester; 8. thermometer and hygrometer. DETAILED DESCRIPTION

[0043] The present invention is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention.

[0044] A new fan simulated pressure difference air volume test bench, such as Figure 1As shown, it includes a circular tubular ventilation duct 2, on which a front static pressure ring 3 and a rear static pressure ring 6 for measuring wind pressure are provided, between which a wind resistance regulating valve 4 for adjusting wind pressure and wind volume is provided, and on the side of the wind resistance regulating valve 4 close to the rear static pressure ring 6, an air flow rectifier 5 is provided, and the wind resistance regulating valve 4 is arranged on the end face of the air flow rectifier 5, and the irregular air flow passing through the wind resistance regulating valve 4 is rectified into a regular air flow by the air flow rectifier 5, so as to facilitate the rear static pressure ring 6 to measure the wind pressure, and the static pressure difference between the front static pressure ring 3 and the rear static pressure ring 6 is the simulated wind resistance. The ventilation duct 2 is also provided with an air volume tester 7 located on the side of the rear static pressure ring 6 away from the front static pressure ring 3, and the air volume is tested by the air volume tester 7, and the air volume of the fresh air fan under the simulated wind resistance can be tested by combining the simulated wind resistance.

[0045] The fresh air fan generally includes four air inlets and outlets: outdoor fresh air inlet, indoor fresh air outlet, indoor return air inlet and outdoor return air outlet. Therefore, the fresh air fan simulated pressure difference air volume test bench needs to be applicable to the four air inlets and outlets at the same time. Figure 2 As shown, one end of the ventilation duct 2 close to the front static pressure ring 3 is used to connect with the two air outlets of the fresh air fan 1, such as Figure 3 As shown, one end of the ventilation duct 2 close to the rear static pressure ring 6 is used to connect with the two air inlets of the fresh air fan 1, so as to realize the air volume test under the simulated pressure difference of the four air inlets and outlets of the fresh air fan.

[0046] The ventilation duct 2 can be selected according to the size of the air inlet and outlet of the fresh air fan, and the material is generally a stainless steel pipe. However, in order to improve the versatility of the ventilation duct 2, Figure 1 Shown and Figure 2 As shown, reducers 21 are detachably connected at both ends of the ventilation duct 2. Different reducers 21 can be used to connect the ventilation duct 2 to the air inlet and outlet of different fresh air fans, thereby improving the application range of the test bench. The detachable connection between the reducer 21 and the ventilation duct 2 can be a threaded connection or a clamping connection, and in order to reduce the resistance effect of the reducer 21 when the reducer 21 changes diameter, the diameter change angle α of the reducer 21 shall not be greater than 15°.

[0047] like Figure 2 and Figure Figure 3As shown, the present invention can be used in the development stage or installation stage of a new air blower, and can also be used for a motor blower, with a wide range of applications. Specifically, according to the test purpose, a filter is selected to be installed in the new air blower or not, and the wind pressure and air volume are adjusted by adjusting the wind resistance regulating valve 4. The static pressure difference between the front static pressure ring 3 and the rear static pressure ring 6 is the simulated pressure difference of the air duct or the filter. The air volume tester 7 directly reads the same amount, and the pressure-air volume curve of the new air system can be tested. The simulated pressure difference can be adjusted at will by the wind resistance regulating valve 4, and the simulated pressure difference is directly obtained according to the front static pressure ring 3 and the rear static pressure ring 6. The air volume is directly obtained by the air volume tester 7, and the test is convenient. In the development stage of the new air blower, design parameters are provided for the designers of the new air blower, which is convenient for the designers to select the fan, optimize the air duct, etc., and design parameters are provided for the air duct in the installation stage of the new air blower. At the same time, the ventilation duct 2 can also be directly connected to the air outlet of the motor blower to simulate different wind resistances and quickly draw the wind resistance curve of the corresponding motor blower.

[0048] like Figure 1 and Figure 4 As shown, in this embodiment, the front static pressure ring 3 and the rear static pressure ring 6 have the same structure, both of which include four static pressure holes 22 connected to the ventilation duct 2 and arranged in a circumferential array on the side wall of the ventilation duct 2, each static pressure hole 22 is connected to a hard air guide tube 23 integrally formed with the ventilation duct 2, and one end of each group of four air guide tubes 23 away from the static pressure hole 22 is connected through a hose 31, and the hose 31 is connected to a pressure gauge 33 for measuring the front wind pressure and the rear wind pressure. Among them, a ball head 24 with two ends opened is provided at one end of each air guide tube 23 away from the static pressure hole 22, and a soft hole 32 matched with the ball head 24 is provided on the hose 31, and the ball head 24 and the soft hole 32 are used to realize the connection between the air guide tube 23 and the hose 31, which is not only convenient for the installation and replacement of the hose 31, but also has good sealing performance.

[0049] like Figure 5 As shown, the wind resistance regulating valve 4 adopts a fan-shaped structure or a shutter-type structure, which can adjust the size of the ventilation opening, thereby achieving the purpose of adjusting the wind pressure and air volume. In this embodiment, a fan-shaped wind resistance regulating valve 4 is selected. Figure 6 As shown, in this embodiment, the airflow straightener 5 is a perforated plate structure including a plurality of straightening holes 51, and the axial direction of the straightening holes 51 is parallel to the axial direction of the ventilation duct 2, and the irregularly flowing airflow at the front end is flattened into a regularly flowing airflow. The airflow straightener 5 is made of anti-corrosion material, and the edge of the opening should not have burrs or rounding, and there should be no visible damage, especially during transportation and cleaning, to prevent it from being damaged.

[0050] like Figure 1As shown, in this embodiment, the air volume tester 7 can use an anemometer to measure the wind speed and then calculate the air volume according to the diameter of the ventilation duct 2 and automatically display it. The anemometer can be a thermal, wind wheel or pitot tube type. In addition, considering that different temperatures and humidities will cause changes in air viscosity, thereby causing deviations in test results, in order to ensure the consistency of the test, a thermometer and hygrometer 8 is also located on the side of the air volume tester 7 away from the rear static pressure ring 6 on the ventilation duct 2, and the test temperature of the thermometer and hygrometer 8 is 23±5℃, and the relative humidity is 50±20%.

[0051] Since there will be turbulence when the air flows in and out of the ventilation duct 2, in order to reduce the influence of turbulence on the wind pressure and air volume test, it is necessary to design the position of the front static pressure ring 3, the air flow rectifier 5, the air volume tester 7 and the structure of the air flow rectifier 5. Figure 1 As shown, the diameter of the ventilation duct 2 is D, and the distance between the front static pressure ring 3 and the port at the air inlet end of the ventilation duct 2 is L1, and L1>4D, to avoid turbulence at the front static pressure ring 3, resulting in inaccurate wind pressure tested by the front static pressure ring 3. The distance between the airflow rectifier 5 and the air volume tester 7 close to the end of the air volume tester 7 is L2, and L2>4D, to ensure that the static pressure difference after rectification by the airflow rectifier 5 has as little influence on the Pitot tube in the air volume tester 7 when measuring wind pressure, thereby ensuring the accuracy of the air volume measured by the air volume tester 7. The distance between the air volume tester 7 and the port at the air outlet end of the ventilation duct 2 is L3, and L3>4D, to avoid the influence of the turbulence at the air outlet on the air volume tester 7, resulting in inaccurate air volume measurement by the air volume tester 7.

[0052] like Figure 1 and Figure 6 As shown, the several rectifying holes 51 on the airflow rectifying device 5 are square holes with a side length of w, and w=0.075D; the thickness of the orifice plate between adjacent rectifying holes 51 is e, and e≤0.005D; the axial length of the airflow rectifying device 5 is L, and L=0.45D, thus ensuring that the airflow rectifying device 5 can effectively stabilize the airflow.

[0053] Working principle and use method of the present invention:

[0054] The present invention can be used in the development stage or installation stage of the fresh air fan, and can also be used for motor fans, and has a wide range of applications. According to the test purpose, a filter is installed in the fresh air fan or not. When measuring the air outlet of the fresh air fan 1, the air outlet of the fresh air fan 1 is connected to one end of the ventilation duct 2 close to the front static pressure ring 3; when measuring the air inlet of the fresh air fan 1, the air inlet of the fresh air fan 1 is connected to one end of the ventilation duct 2 close to the rear static pressure ring 6.

[0055] The wind pressure and air volume are adjusted by adjusting the wind resistance regulating valve 4. The static pressure difference between the front static pressure ring 3 and the rear static pressure ring 6 is the simulated pressure difference of the air duct or filter. The air volume tester 7 directly reads the same amount, and the pressure-air volume curve of the fresh air system can be tested, and the real-time temperature and humidity of the thermometer and hygrometer 8 can be recorded. Among them, the simulated pressure difference can be adjusted at will through the wind resistance regulating valve 4, and the simulated pressure difference is directly obtained according to the front static pressure ring 3 and the rear static pressure ring 6, and the air volume is directly obtained by the air volume tester 7, which is convenient for testing.

[0056] In the development stage of new fans, design parameters are provided to new fan designers to facilitate fan selection, air duct optimization, etc., and design parameters are provided for air ducts in the installation stage of new fans. At the same time, ventilation duct 2 can also be directly connected to the air outlet of the motor fan to simulate different wind resistances and quickly draw the wind resistance curve of the corresponding motor fan.

[0057] The above description shows and describes the preferred embodiments of the present invention. As mentioned above, it should be understood that the present invention is not limited to the form disclosed herein, and should not be regarded as excluding other embodiments, but can be used in various other combinations, modifications and environments, and can be modified within the scope of the invention concept described herein through the above teachings or the technology or knowledge of the relevant field. The changes and modifications made by those skilled in the art do not depart from the spirit and scope of the present invention, and should be within the scope of protection of the claims attached to the present invention.

Claims

1. A new air blower simulated pressure difference air volume test bench, characterized by: The invention comprises a ventilation duct (2), wherein the ventilation duct (2) is provided with a front static pressure ring (3) and a rear static pressure ring (6), a wind resistance regulating valve (4) is provided between the front static pressure ring (3) and the rear static pressure ring (6), and the ventilation duct (2) is provided with an air volume tester (7) located on the side of the rear static pressure ring (6) away from the front static pressure ring (3); an end of the ventilation duct (2) close to the front static pressure ring (3) is used to be connected to the air outlet of the fresh air fan (1), and an end of the ventilation duct (2) close to the rear static pressure ring (6) is used to be connected to the air inlet of the fresh air fan (1); An airflow rectifier (5) is provided between the wind resistance regulating valve (4) and the rear static pressure ring (6), and the wind resistance regulating valve (4) is arranged on the end surface of the airflow rectifier (5); the airflow rectifier (5) is a perforated plate structure including a plurality of rectifying holes (51), and the axial direction of the rectifying holes (51) is parallel to the axial direction of the ventilation duct (2); The diameter of the ventilation duct (2) is D, the distance between the front static pressure ring (3) and the ventilation duct (2) and the end port close to it is L1, and L1>4D; The distance between the end of the airflow rectifier (5) close to the air volume tester (7) and the air volume tester (7) is L2, and L2>4D; The distance between the air volume tester (7) and the ventilation duct (2) and one end port thereof close thereto is L3 and L3>4D; The ventilation duct (2) is also provided with a thermometer and hygrometer (8), and the thermometer and hygrometer (8) is located on a side of the air volume tester (7) away from the rear static pressure ring (6).

2. The new air blower simulated pressure difference air volume test bench according to claim 1 is characterized in that: The test temperature of the thermohygrometer (8) is 23±5°C, and the relative humidity is 50±20%.

3. The new air blower simulated pressure difference air volume test bench according to claim 1 is characterized in that: Both ends of the ventilation duct (2) are detachably connected with a reducing adapter (21), and the reducing angle of the reducing adapter (21) is ≤15°.

4. The new air blower simulated pressure difference air volume test bench according to claim 1 is characterized in that: The front static pressure ring (3) and the rear static pressure ring (6) have the same structure, and both include four static pressure holes (22) arranged in a circumferential array on the side wall of the ventilation duct (2) and connected to the ventilation duct (2). Each group of four static pressure holes (22) are connected via a hose (31), and the hose (31) is connected to a pressure gauge (33).

5. The new air blower simulated pressure difference air volume test bench according to claim 4 is characterized in that: The static pressure hole (22) on the ventilation duct (2) is connected to an air guide tube (23) arranged axially along the static pressure hole (22); a ball head (24) is provided at one end of the air guide tube (23) away from the static pressure hole (22); and a soft hole (32) cooperating with the ball head (24) is provided on the hose (31).

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