Ejector type low noise wind tunnel power section with ultra-wide flow regulation range and working method

Abstract

The application discloses an ejector type low-noise wind tunnel power section with an ultra-wide flow regulation range and a working method. The wind tunnel power section comprises an air inlet, an inner duct, a small fan, a large fan, a non-full-circumference support structure, an actuator outer slide, an on-off execution pipe section, an outer duct, an air outlet and the like. The application is based on a wind tunnel power section design scheme with a combination type parallel structure of the small and large fans and a working method of the wind tunnel power section with the on-off execution pipe section to realize the on-off of the flow passages of the small and large fans. The application can realize the continuous measurement of aerodynamic parameters of the wind tunnel in an ultra-wide flow range without replacing the wind tunnel power section. The low-energy low-speed air in the outer duct is mixed with the air in the inner duct through the ejector structure, so that the flow speed and the noise level at the outlet of the wind tunnel are reduced, the noise propagation range is greatly reduced, and the application and the working method have the advantages of low flow resistance, low noise, simple operation, time and labor saving and the like.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of gas delivery or wind tunnel flow rate measurement, in particular to an ejector type wind tunnel power section with ultra-wide flow rate regulation range and low noise and a working method thereof. BACKGROUND

[0002] A wind tunnel is one of important metrological equipment for simulating a specific flow field and measuring basic parameters such as flow rate. The power section of the wind tunnel is usually composed of a single fan and a pipe wall connected to the wind tunnel. The flow rate range of the fan is narrow. In order to expand the flow rate range of the wind tunnel, the traditional method needs to use two or more wind tunnel power sections with different flow rate ranges. When using two or more wind tunnel power sections with different flow rate ranges, the fan of the running wind tunnel power section needs to be stopped, then the original wind tunnel power section is moved away, a new wind tunnel power section is moved in and connected to the wind tunnel, and finally the new wind tunnel power section is started to complete the measurement of the related aerodynamic parameters of the wind tunnel. However, the size and mass of the wind tunnel power section are large. The above-mentioned process of replacing the wind tunnel power section not only consumes time and effort, but also stops the measurement during the replacement of the wind tunnel power section, so that the continuous measurement of the aerodynamic parameters of the wind tunnel cannot be realized when the flow rate range of the wind tunnel continuously changes in an ultra-wide range. Therefore, the test personnel of the wind tunnel cannot continuously measure in an ultra-wide flow rate range. In addition, when the test personnel of the wind tunnel carry out the measurement in an ultra-wide flow rate regulation range, the wind tunnel produces noise of 95 decibels or more, the noise propagation range is large, and the physical and mental health of the test personnel and the staff around the wind tunnel are affected. The above-mentioned problems of continuous measurement in an ultra-wide flow rate range and noise reduction of the wind tunnel power section seriously trouble the test personnel and the designers of the wind tunnel. At present, there is no mature technical solution to solve the above-mentioned problems. SUMMARY

[0003] The present application relates to the technical field of gas delivery or wind tunnel flow rate measurement, in particular to an ejector type wind tunnel power section with ultra-wide flow rate regulation range and low noise and a working method thereof.

[0004] The present application achieves the above-mentioned purpose by the following technical solutions:

[0005] The ejector type ultra-wide flow regulation range low noise wind tunnel power section comprises an air inlet (1), an inlet section outer wall (2), a large fan inlet outer wall (3), a power section large fan support section outer wall (4), an inner duct outlet section outer wall (5), an ejector type inner duct outlet (6), a small fan (7), a large fan (8), a non-full-circumferential support structure (9), an actuator outer slide (10), an on-off actuator pipe section (11), an outer duct inlet (12), an outer duct (13), an outer duct outlet (14), an outer duct to inner duct conveying passage (15), an inner duct to outer duct conveying passage (16), wherein the air inlet (1) is connected with the inlet section outer wall (2), the large fan inlet outer wall (3) is connected with the power section large fan support section outer wall (4), the inner duct outlet section outer wall (5) is connected with the power section large fan support section outer wall (4), the outer duct to inner duct conveying passage (15) and the inner duct to outer duct conveying passage (16) are connected with the inner duct outlet section outer wall (5), the ejector type inner duct outlet (6) is connected with the outer duct to inner duct conveying passage (15) and the inner duct to outer duct conveying passage (16), the outer duct inlet (12) is connected with the outer duct (13), the outer duct outlet (14) is connected with the outer duct (13), a large fan guide vane fixing ring (84) is fixed to the inner side of the power section large fan support section outer wall (4), the small fan (7) comprises a small fan inlet flow guide structure (71), a small fan moving vane (72), a small fan guide vane (73), a small fan guide vane fixing ring (74) and a small fan motor (75), the large fan (8) comprises a large fan inlet flow guide structure (81), a large fan moving vane (82), a large fan guide vane (83), a large fan guide vane fixing ring (84), a large fan outlet flow guide structure (85) and a large fan motor (86), the large fan motor (86) is connected with the large fan inlet flow guide structure (81), the large fan moving vane (82), the large fan guide vane (83) and the large fan outlet flow guide structure (85) respectively, the small fan motor (75) is connected with the small fan inlet flow guide structure (71), the small fan moving vane (72), the small fan guide vane (73), the small fan guide vane fixing ring (74) and the large fan inlet flow guide structure (81) respectively, the axial cross-sectional area of the inlet section outer wall (2) continuously increases from the inlet to the outlet, the axial cross-sectional area of the large fan inlet outer wall (3) continuously decreases from the inlet to the outlet, the axial cross-sectional area of the inner duct outlet section outer wall (5) continuously increases from the inlet to the outlet, the non-full-circumferential support structure (9) is fixed to the position where the inlet section outer wall (2) and the large fan inlet outer wall (3) are connected, the actuator outer slide (10) is fixed to the non-full-circumferential support structure (9), the non-full-circumferential support structure (9) is a non-full-circumferential closed support structure through which gas can pass, the on-off actuator pipe section (11) moves in the axial direction in the annular gap between the actuator outer slide (10) and the small fan guide vane fixing ring (74) and can reach the wall surface of the inlet section outer wall (2) or the wall surface of the large fan inlet flow guide structure (81),The maximum flow value of the small fan (7) flow range is greater than the minimum flow value of the large fan (8) flow range.

[0006] The working method of the ejector type low noise wind tunnel power section with super wide flow regulation range, comprising a small fan working condition and a large fan working condition, the small fan working condition refers to the movement of the on-off execution pipe section (11) along the annular gap between the execution outer slide (10) and the small fan guide vane fixed ring (74) to the inlet section outer wall (2) wall surface, at this time, a part of air flows into the inlet section outer wall (2) wall surface from the inlet section outer wall (2) wall surface, through the space surrounded by the inner wall surface of the on-off execution pipe section (11), the outer wall surface of the small fan inlet guide structure (71), and the small fan (7) small fan moving vane (72), small fan guide vane (73), and then flows out from the outer wall surface of the large fan inlet guide structure (81), sequentially enters the static large fan moving vane (82) area, large fan guide vane (83) area, the area surrounded by the inner wall surface of the inner duct outlet section outer wall (5) and the outer wall surface of the large fan outlet guide structure (85), the area surrounded by the inner wall surface of the inner duct to outer duct conveying channel (15) and the inner wall surface of the inner duct to outer duct conveying channel (16), and then flows out from the ejector type inner duct outlet (6), another part of air flows into the outer duct (13) from the outer duct inlet (12), and then flows out from the outer duct (13) from the outer duct inlet (12), and then flows out from the outer duct (13) from the outer duct inlet (12), and then flows out from the outer duct (13) from the outer duct inlet (12), and then flows out from the outer duct (13) from the outer duct inlet (12), and then flows out from the outer duct (13) from the outer duct inlet (12), and then flows out from the outer duct (13) from the outer duct inlet (12), and then flows out from the outer duct (13) from the outer duct inlet (12), and then flows out from the outer duct (13) from the outer duct inlet (12), and then flows out from the outer duct (13) from the outer duct inlet (12), and then flows out from the outer duct (13) from the outer duct inlet (12), and then flows out from the outer duct (13) from the outer duct inlet (12), and then flows out from the outer duct (13) from the outer duct inlet (12), and then flows out from the outer duct (13) from the outer duct inlet (12), and then flows out from the outer duct (13) from the outer duct inlet (12), and then flows out from the outer duct (13) from the outer duct inlet (12), and then flows out from the outer duct (13) from the outer duct inlet (12), and then flows out from the outer duct (13) from the outer duct inlet (12), and then flows out from the outer duct (13) from the outer duct inlet (12), and thenThe large fan working condition refers to that the on-off execution pipe section (11) moves along the annular gap between the execution outer slide (10) and the small fan guide vane fixed ring (74) to the wall surface of the large fan inlet guide structure (81). At this time, part of the air flows from the ejector type super wide flow regulation range low noise wind tunnel power section air inlet (1) into, flows through the inside of the inlet section outer wall (2), the inside of the large fan inlet outer wall (3), the outside of the small fan inlet guide structure (71), the outside of the execution outer slide (10), and the outside of the on-off execution pipe section (11), and then enters the large fan moving vane (82) area, the large fan guide vane (83) area, and the area surrounded by the inner wall surface of the inner channel outlet section outer wall (5) and the outer wall surface of the large fan outlet guide structure (85), and the area surrounded by the inner wall surface of the outer channel to inner channel delivery channel (15) and the inner wall surface of the inner channel to outer channel delivery channel (16), and then flows out from the ejector type inner channel air outlet (6). Another part of the air flows from the outer channel inlet (12) into the area surrounded by the inner wall surface of the outer channel (13) front part, the outer wall surface of the outer channel to inner channel delivery channel (15), and the outer wall surface of the inner channel to outer channel delivery channel (16), and then flows out from the ejector type inner channel air outlet (6). The two air flows are mixed to form an air flow, which flows out from the outer channel outlet (14) to the ejector type super wide flow regulation range low noise wind tunnel power section.

[0007] The beneficial effects of the present application are:

[0008] Currently, there is no mature technical scheme of the low-noise wind tunnel power section with super-wide flow range and continuous measurement of aerodynamic parameters. In view of the low-noise, super-wide flow range and use condition without replacing the power section, the application provides a design scheme of the ejector type low-noise wind tunnel power section with super-wide flow range and high operability and low cost. The application uses the independently developed small fan with 12 times flow regulation capacity and the large fan with 6 times flow regulation capacity, adopts the design scheme based on the combined parallel structure of the small and large fans, controls the on-off of the flow passage of the small and large fans by the creative design of the on-off execution pipe section, and forms two flow schemes by the way of the working medium through the wind tunnel power section, one is that the large fan is static, the working medium only passes through the small fan to do work to boost and accelerate, and the other is that the small fan is static and is completely isolated, and the working medium only passes through the large fan to do work to boost and accelerate. Based on the above two forms, the flow regulation range of the small fan and the flow regulation range of the large fan can be superimposed, so that the combined wind tunnel power section has a super-wide flow regulation range with a maximum and minimum flow ratio of 63 times, thereby meeting the use requirement of the wind tunnel in the super-wide flow range for continuously measuring aerodynamic parameters without replacing the power section. Compared with the opening and closing scheme of the vertical movement or the inclined movement, the opening and closing scheme of the horizontal movement of the execution outer slide and the on-off execution pipe section can greatly reduce the flow resistance in the wind tunnel power section, thereby eliminating the swing and damage of the execution and support structure caused by the karman vortex street or the low-pressure unstable cyclone, and eliminating the influence of the karman vortex street or the low-pressure unstable cyclone on the measurement accuracy of the wind tunnel, so that the opening and closing scheme of the horizontal movement of the execution outer slide and the on-off execution pipe section is the solution with the lowest cost, high reliability and longest service life. In order to greatly reduce the noise level of the wind tunnel power section, the application adopts the ejector structure, introduces the low-energy low-speed air in the outer channel to mix with the air in the inner channel, thereby reducing the outlet flow velocity and noise level of the wind tunnel, greatly reducing the noise propagation range, and protecting the physical and mental health of the test personnel and the staff around the wind tunnel. In addition, the axial cross-sectional area of the inlet section outer wall shows a continuous increasing trend from the inlet to the outlet, the axial cross-sectional area of the large fan inlet outer wall shows a continuous decreasing trend from the inlet to the outlet, and the axial cross-sectional area of the outlet section outer wall shows a continuous increasing trend from the inlet to the outlet. The above structural design can greatly reduce the flow resistance of the wind tunnel power section, so that the wind tunnel power section is more energy-saving and has more advanced aerodynamic performance. BRIEF DESCRIPTION OF DRAWINGS

[0009] Figure 1 is a schematic view of the ejector type low-noise wind tunnel power section with super-wide flow regulation range.

[0010] Figure 2is a working state schematic diagram of the ejector type super-wide flow regulation range low-noise wind tunnel power section of the present application, wherein (a) is a small fan working condition, and (b) is a large fan working condition. DETAILED DESCRIPTION

[0011] The present application is further described below in conjunction with the accompanying drawings:

[0012] As Figure 1As shown, the ejector type ultra-wide flow regulation range low noise wind tunnel power section includes an air inlet (1), an inlet section outer wall (2), a large fan inlet outer wall (3), a power section large fan support section outer wall (4), an inner duct outlet section outer wall (5), an ejector type inner duct outlet (6), a small fan (7), a large fan (8), a non-full-circumferential support structure (9), an actuator outer slide (10), an on-off actuator pipe section (11), an outer duct inlet (12), an outer duct (13), an outer duct outlet (14), an outer duct to inner duct delivery channel (15), an inner duct to outer duct delivery channel (16), wherein the air inlet (1) is connected with the inlet section outer wall (2), the large fan inlet outer wall (3) is connected with the power section large fan support section outer wall (4), the inner duct outlet section outer wall (5) is connected with the power section large fan support section outer wall (4), the outer duct to inner duct delivery channel (15) and the inner duct to outer duct delivery channel (16) are connected with the inner duct outlet section outer wall (5), the ejector type inner duct outlet (6) is connected with the outer duct to inner duct delivery channel (15) and the inner duct to outer duct delivery channel (16), the outer duct inlet (12) is connected with the outer duct (13), the outer duct outlet (14) is connected with the outer duct (13), the large fan guide vane fixing ring (84) is fixed inside the power section large fan support section outer wall (4), the small fan (7) includes a small fan inlet flow guide structure (71), a small fan moving vane (72), a small fan guide vane (73), a small fan guide vane fixing ring (74), and a small fan motor (75), the large fan (8) includes a large fan inlet flow guide structure (81), a large fan moving vane (82), a large fan guide vane (83), a large fan guide vane fixing ring (84), a large fan outlet flow guide structure (85), and a large fan motor (86), the large fan motor (86) is connected with the large fan inlet flow guide structure (81), the large fan moving vane (82), the large fan guide vane (83), and the large fan outlet flow guide structure (85), respectively, the small fan motor (75) is connected with the small fan inlet flow guide structure (71), the small fan moving vane (72), the small fan guide vane (73), the small fan guide vane fixing ring (74), and the large fan inlet flow guide structure (81), respectively, the axial cross-sectional area of the inlet section outer wall (2) continuously increases from the inlet to the outlet, the axial cross-sectional area of the large fan inlet outer wall (3) continuously decreases from the inlet to the outlet, the axial cross-sectional area of the inner duct outlet section outer wall (5) continuously increases from the inlet to the outlet, the non-full-circumferential support structure (9) is fixed at the position where the inlet section outer wall (2) and the large fan inlet outer wall (3) are connected, the actuator outer slide (10) is fixed on the non-full-circumferential support structure (9), the non-full-circumferential support structure (9) is a non-full-circumferential closed support structure through which gas can pass, the on-off actuator pipe section (11) moves in the axial direction in the annular gap between the actuator outer slide (10) and the small fan guide vane fixing ring (74), and can reach the wall surface of the inlet section outer wall (2) or the wall surface of the large fan inlet flow guide structure (81),The maximum flow value of the small fan (7) flow range is greater than the minimum flow value of the large fan (8) flow range.

[0013] As a preferred embodiment of the present application, as Figure 2As shown, the working method of the ejector type super-wide flow regulation range low-noise wind tunnel power section includes a small fan working condition and a large fan working condition. The small fan working condition refers to that the on-off execution pipe section (11) moves to the wall surface of the inlet section outer wall (2) along the annular gap between the execution outer slide (10) and the small fan guide vane fixed ring (74). At this time, a part of air flows from the inlet (1) of the ejector type super-wide flow regulation range low-noise wind tunnel power section, flows through the space surrounded by the inner wall surface of the on-off execution pipe section (11), the outer wall surface of the small fan inlet guide structure (71), and the front part of the wall surface of the inlet section outer wall (2), enters the small fan (7), and accelerates the small fan moving vane (72) and the small fan guide vane (73). Subsequently, the air flows out from the outer side of the wall surface of the large fan inlet guide structure (81), sequentially enters the area of the stationary large fan moving vane (82), the area of the large fan guide vane (83), the area surrounded by the inner wall surface of the inner duct outlet section outer wall (5) and the outer wall surface of the large fan outlet guide structure (85), the area surrounded by the inner wall surface of the inner duct to outer duct conveying channel (15) and the inner wall surface of the outer duct to inner duct conveying channel (16), and then flows out from the ejector type inner duct outlet (6). Another part of air flows from the outer duct inlet (12) into the area surrounded by the inner wall surface of the front part of the outer duct (13), the outer wall surface of the outer duct to inner duct conveying channel (15), and the outer wall surface of the inner duct to outer duct conveying channel (16). Subsequently, the air enters the area surrounded by the inner wall surface of the rear part of the outer duct (13) together with the air flowing out from the ejector type inner duct outlet (6). After mixing, the two air flows form one air flow, which flows out from the outer duct outlet (14) of the ejector type super-wide flow regulation range low-noise wind tunnel power section.The large fan working condition refers to that the on-off execution pipe section (11) moves along the annular gap between the execution outer slide (10) and the small fan guide vane fixed ring (74) to the wall surface of the large fan inlet guide structure (81). At this time, part of the air flows into the inlet of the ejector type super-wide flow regulation range low-noise wind tunnel power section (1), flows through the inside of the inlet section outer wall (2), the inside of the large fan inlet outer wall (3), the outside of the small fan inlet guide structure (71), the outside of the execution outer slide (10), and the outside of the on-off execution pipe section (11), and then enters the large fan moving blade (82) area and the large fan guide vane (83) area in sequence, accelerates into the area surrounded by the inner wall surface of the inner channel outlet section outer wall (5) and the outer wall surface of the large fan outlet guide structure (85), the inner wall surface of the outer channel to inner channel delivery channel (15), and the inner wall surface of the inner channel to outer channel delivery channel (16), and then flows out of the ejector type inner channel air outlet (6). Another part of the air flows into the area surrounded by the inner wall surface of the outer channel inlet (12), the outer wall surface of the outer channel to inner channel delivery channel (15), and the outer wall surface of the inner channel to outer channel delivery channel (16), and then flows out of the ejector type inner channel air outlet (6). The two air flows are mixed to form an air flow, which flows out of the outer channel outlet (14) of the ejector type super-wide flow regulation range low-noise wind tunnel power section.

[0014] The technical scheme of the present application is not limited to the above specific embodiments, and any technical modification made according to the technical scheme of the present application falls within the protection scope of the present application.

Claims

1. The ejector-type ultra-wide flow adjustment range low-noise wind tunnel power section is characterized by: The invention comprises an air inlet (1), an outer wall of an inlet section (2), an outer wall of a large fan inlet (3), an outer wall of a large fan support section of a power section (4), an outer wall of an inner channel outlet section (5), an ejection-type inner channel air outlet (6), a small fan (7), a large fan (8), a non-full-circumference support structure (9), an outer slideway of an actuator (10), an on-off actuator section (11), an outer duct inlet (12), an outer duct (13), an outer duct outlet (14), a conveying channel from the outer duct to the inner channel (15), and a conveying channel from the inner channel to the outer duct (16), wherein the air inlet (1) is connected to the outer wall of the inlet section (2), the outer wall of the large fan inlet (3) is connected to the outer wall of the large fan support section of the power section (4), the outer wall of the inner channel outlet section (5) is connected to the large fan support section of the power section The outer wall (4) of the fan support section is connected, the outer duct to inner duct conveying channel (15) and the inner duct to outer duct conveying channel (16) are connected to the outer wall (5) of the inner duct outlet section, the ejection type inner duct outlet (6) is connected to the outer duct to inner duct conveying channel (15) and the inner duct to outer duct conveying channel (16), the outer duct inlet (12) is connected to the outer duct (13), the outer duct outlet (14) is connected to the outer duct (13), the large fan guide vane fixing ring (84) is fixed on the inner side of the outer wall (4) of the large fan support section of the power section, the small fan (7) includes a small fan inlet guide structure (71), a small fan rotor blade (72), a small fan guide vane (73), a small fan guide vane fixing ring (74) and a small fan motor (75), and the large fan The fan (8) includes a large fan inlet guide structure (81), a large fan moving blade (82), a large fan guide blade (83), a large fan guide blade fixing ring (84), a large fan outlet guide structure (85) and a large fan motor (86). The large fan motor (86) is respectively connected to the large fan inlet guide structure (81), the large fan moving blade (82), the large fan guide blade (83) and the large fan outlet guide structure (85). The small fan motor (75) is respectively connected to the small fan inlet guide structure (71), the small fan moving blade (72), the small fan guide blade (73), the small fan guide blade fixing ring (74) and the large fan inlet guide structure (81). The axial cross-sectional area of ​​the outer wall (2) of the inlet section increases continuously from the inlet to the outlet. The axial cross-sectional area of ​​the large fan inlet outer wall (3) shows a trend of continuously decreasing from the inlet to the outlet, and the axial cross-sectional area of ​​the inner channel outlet section outer wall (5) shows a trend of continuously increasing from the inlet to the outlet. The non-full-circumference support structure (9) is fixed at the position where the inlet section outer wall (2) and the large fan inlet outer wall (3) are connected. The actuator outer slide (10) is fixed to the non-full-circumference support structure (9). The non-full-circumference support structure (9) is a non-full-circumference closed support structure through which gas can pass. The on-off actuator pipe section (11) is limited to the annular gap between the actuator outer slide (10) and the small fan guide vane fixing ring (74) and moves axially, and can reach the wall surface of the inlet section outer wall (2) or the wall surface of the large fan inlet guide structure (81).The maximum flow rate value of the flow rate range of the small fan (7) is greater than the minimum flow rate value of the flow rate range of the large fan (8).

2. The operating method of the jet-type ultra-wide flow regulation range low-noise wind tunnel power section according to claim 1 is characterized by: The working method includes a small fan working condition and a large fan working condition. The small fan working condition refers to the on-off execution pipe section (11) moving along the annular gap between the actuator outer slideway (10) and the small fan guide vane fixing ring (74) to the wall surface of the inlet section outer wall (2). At this time, a part of the air flows in from the induced ultra-wide flow adjustment range low noise wind tunnel power section air inlet (1), flows through the space surrounded by the front part wall surface of the inlet section outer wall (2) and the inner wall surface of the on-off execution pipe section (11) and the outer wall surface of the small fan inlet guide structure (71), enters the small fan rotor blade (72) and the small fan guide vane (73) of the small fan (7) to accelerate, and then flows out from the outer side of the wall surface of the large fan inlet guide structure (81), and enters the stationary large fan rotor blade (82) area and the large fan guide vane (83) area in sequence. , the area enclosed by the inner wall surface of the outer wall of the inner duct outlet section (5) and the outer wall surface of the large fan outlet guide structure (85), the area enclosed by the inner wall surface of the outer duct to inner duct conveying channel (15) and the inner wall surface of the inner duct to outer duct conveying channel (16), and then flows out from the ejection type inner duct outlet (6), and the other part of the air flows from the outer duct inlet (12) into the area enclosed by the inner wall surface of the front part of the outer duct (13) and the outer wall surface of the outer duct to inner duct conveying channel (15) and the outer wall surface of the inner duct to outer duct conveying channel (16), and then enters the area enclosed by the inner wall surface of the rear part of the outer duct (13) together with the air flowing out from the ejection type inner duct outlet (6), and the two air flows are mixed to form one air flow, which flows out from the outer duct outlet (14) to form the ejection type ultra-wide flow adjustment range low noise wind tunnel power section;The working condition of the large fan refers to the on-off execution pipe section (11) moving along the annular gap between the actuator outer slideway (10) and the small fan guide vane fixing ring (74) to the wall surface of the large fan inlet guide structure (81). At this time, a part of the air flows in from the injection-type ultra-wide flow adjustment range low noise wind tunnel power section air inlet (1), flows through the inner side of the inlet section outer wall (2), the inner side of the large fan inlet outer wall (3), and the outer side of the small fan inlet guide structure (71), the outer side of the actuator outer slideway (10), and the outer side of the on-off execution pipe section (11), and enters the large fan motor vane (82) area and the large fan guide vane (83) area in turn, and accelerates to enter the inner wall surface of the inner channel outlet section outer wall (5) and the large fan outlet guide structure (8 5), the area surrounded by the outer wall of the outer duct to inner duct conveying channel (15), and the area surrounded by the inner wall of the inner duct to outer duct conveying channel (16), and then flows out from the ejection type inner duct outlet (6). Another part of the air flows from the outer duct inlet (12) into the area surrounded by the front inner wall of the outer duct (13), the outer wall of the outer duct to inner duct conveying channel (15), and the outer wall of the inner duct to outer duct conveying channel (16), and then enters the area surrounded by the rear inner wall of the outer duct (13) together with the air flowing out from the ejection type inner duct outlet (6). The two air flows are mixed to form one air flow, and then flows out from the outer duct outlet (14) to the ejection type ultra-wide flow adjustment range low noise wind tunnel power section.

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