A double-reflow, low-vibration, temperature-controllable, high-efficiency anechoic wind tunnel for parachuting training

Abstract

A double-reflux low-vibration temperature-controllable high-efficiency parachuting training anechoic wind tunnel belongs to the field of parachuting training wind tunnels. It includes a wind tunnel body, a power system and a refrigeration system, and the power system and the refrigeration system are both connected to the inside of the wind tunnel body. A plurality of sampling points are arranged inside the wind tunnel body, and each sampling point uses a pneumatic pump to extract gas samples through a water vapor filter and a flow meter, and then sends them to a detector for detection. When the detector detects that the gas sample extracted from any sampling point is unqualified, the monitoring system sends a signal to the sound and light alarm light for real-time alarm, and sends the signal value to the DCS system distributed control system. The present invention solves the problems that the current parachuting wind tunnel does not have a special refrigeration system heat exchanger, needs to be shut down to wait for cooling, the ambient noise in the flight cabin is too loud, there is no parachuting training function, the vibration of the power system will be transmitted to the cave body or the parachuting area, and there is no harmful gas monitoring function, thereby affecting the safety of personnel, and effectively improves the training efficiency.

Description

Technical Field

[0001] The invention relates to a double-reflux low-vibration temperature-controllable high-efficiency parachuting training anechoic wind tunnel, belonging to the field of parachuting training wind tunnels. Background Art

[0002] A parachuting wind tunnel is a vertical wind tunnel that can generate vertical airflow at a certain speed. People enter the airflow in a certain posture, and can float freely in the air without any tools under the strong support of the wind. People can make various flying movements in the air through different postures and changes in the center of gravity to achieve the same effect as real flying. According to official statistics, using wind tunnels for parachute training can effectively shorten the time required for traditional high-altitude training, because in the traditional training mode, parachutists need to overcome the fear of the first "test flight", and it is also accompanied by considerable danger. Under the wind tunnel training mode, this problem can be perfectly solved. Moreover, since the wind tunnel is not affected by natural weather conditions, the instructor can correct the parachutist's aerial movements at any time during training, so the parachuting wind tunnel can shorten the training cycle of parachutists during parachute training. Therefore, it is very necessary to build a parachuting wind tunnel.

[0003] The current skydiving wind tunnels have the following technical problems:

[0004] 1. There is no dedicated refrigeration system heat exchanger. The current wind tunnel only uses corner guide vanes and ventilation windows to discharge heat. Since the cooling capacity of the existing working method is less than the heat output, the temperature in the flight cabin is too high after long-term operation, and the machine needs to be shut down to wait for cooling, which affects the flight experience and training efficiency.

[0005] 2. The ambient noise in the wind tunnel flight cabin is too loud, which is not conducive to the health of on-site communication and training personnel such as coaches guiding trainees;

[0006] 3. It only has the function of taking off from the flight cabin for training, and cannot truly simulate the parachuting process, and the function is relatively simple;

[0007] 4. Generally, the power system of a skydiving wind tunnel is placed directly on the roof of an annex building or on the vertical return section of the tunnel body, which will cause part of the vibration to be transmitted to the tunnel body or the skydiving area, affecting the skydiving experience and equipment safety;

[0008] 5. The interior of a skydiving wind tunnel is a confined space. If harmful gases enter the tunnel, it will endanger personnel safety. Currently, skydiving wind tunnels do not have the function of monitoring harmful gases.

[0009] Therefore, it is urgent to propose a new type of double-reflux, low-vibration, temperature-controllable, and high-efficiency parachuting training anechoic wind tunnel to solve the above technical problems. Summary of the invention

[0010] The purpose of the research and development of the present invention is to solve the problems that the current parachuting wind tunnel does not have a dedicated refrigeration system heat exchanger, needs to be shut down to wait for cooling, the ambient noise in the flight cabin is too loud, there is no parachuting training function, the vibration of the power system will be transmitted to the cave or the parachuting area, and there is no harmful gas monitoring function, which affects the safety of personnel. A brief overview of the present invention is given below to provide a basic understanding of certain aspects of the present invention. It should be understood that this overview is not an exhaustive overview of the present invention. It is not intended to determine the key or important parts of the present invention, nor is it intended to limit the scope of the present invention.

[0011] The technical solution of the present invention:

[0012] A double-reflow low-vibration temperature-controllable high-efficiency parachuting training anechoic wind tunnel, comprising a wind tunnel body, a power system and a refrigeration system, wherein the power system and the refrigeration system are both connected to the interior of the wind tunnel body;

[0013] The wind tunnel body comprises a flight cabin, a first diffusion section, a first corner section, a square-to-round section, a power section, a round-to-square section, a second corner section, a vertical reflow section, a large-angle diffusion section, a third corner section, a stabilizing section, a horizontal contraction section, a fourth corner section, a vertical contraction section, and an independent basic tower for the power section. The first diffusion section is installed on the top of the flight cabin, the first diffusion section is connected to the power section through the first corner section, the power section is connected to the second corner section through the round-to-square section, the second corner section is connected to the top of the vertical reflow section, the bottom of the vertical reflow section is connected to the third corner section through the large-angle diffusion section, and the third corner section is connected to the horizontal contraction section through the stabilizing section. The section is connected to the horizontal contraction section, the horizontal contraction section is connected to the vertical contraction section through the fourth corner section, the top of the vertical contraction section is connected to the bottom of the flight cabin, and the power section is supported by the ground through an independent foundation tower of the power section. A plurality of sampling points are arranged inside the wind tunnel body, and each sampling point uses a pneumatic pump to extract a gas sample through a water vapor filter and a flow meter, and then sends it to the detector for detection. When the detector detects that the gas sample extracted from any sampling point is unqualified, the monitoring system sends a signal to the sound and light alarm lamp to give a real-time alarm, and sends the signal value to the DCS system distributed control system.

[0014] Preferably, the power system is installed in the power section, or is directly connected to the power section.

[0015] Preferably: the power system is a wind speed adjustment device.

[0016] Preferably, the refrigeration system comprises a wind tunnel heat exchanger, and the wind tunnel heat exchanger is installed in the wind tunnel body or directly connected to the wind tunnel body.

[0017] Preferably: the flight cabin comprises a flight cabin steel structure frame, a tempered glass layer, a protective net, a lower waiting cabin, civil engineering embedded plates, connecting steel beams and docking claws; the flight cabin steel structure frame is surrounded by civil engineering embedded plates, and the flight cabin steel structure frame is fixedly connected to the civil engineering embedded plates on all sides by connecting steel beams; a tempered glass layer is arranged inside the flight cabin steel structure frame, the interior of the tempered glass layer encloses a hollow flight chamber, and the tempered glass layer is fixedly connected to the flight cabin steel structure frame by docking claws; a lower waiting cabin is arranged at the bottom of the flight cabin steel structure frame, the lower waiting cabin is provided with a flight cabin entrance, and a protective net is fixedly installed on the flight cabin steel structure frame at the bottom of the lower waiting cabin.

[0018] Preferably: the first diffusion section includes a first diffusion section steel structure frame, a waiting cabin on an acrylic plate and a base, an acrylic plate is arranged inside the first diffusion section steel structure frame, the interior of the acrylic plate encloses a hollow chamber, a base is arranged at the bottom of the first diffusion section steel structure frame, the base is fixedly connected to the flight cabin, an upper waiting cabin is arranged on the top of the first diffusion section steel structure frame, and the upper waiting cabin is provided with a diffusion section entrance.

[0019] Preferably, guide vanes are arranged inside the first corner section, the second corner section, the third corner section and the fourth corner section.

[0020] Preferably, the outer layer of the vertical return section is a concrete structure, the flow channel surface of the inner layer is a perforated sound-absorbing plate, a keel is arranged between the inner layer and the outer layer, and sound-absorbing cotton is filled.

[0021] Preferably, the power system comprises an axial flow fan and a frequency conversion control cabinet, the axial flow fan and the frequency conversion control cabinet are electrically connected, and the air outlet of the axial flow fan is connected to the wind tunnel body.

[0022] The present invention has the following beneficial effects:

[0023] 1. The present invention integrates advanced technologies in the cross-fields of aerodynamic experiment design, refrigeration, noise reduction, vibration reduction and safety monitoring, and has made significant adjustments in terms of specifications, functions, performance and cave material, etc., solving the problems that the current skydiving wind tunnel has no dedicated refrigeration system heat exchanger, needs to be shut down to wait for cooling, the ambient noise in the flight cabin is too loud, there is no skydiving training function, the vibration of the power system will be transmitted to the cave or the skydiving area, and there is no harmful gas monitoring function, thus affecting personnel safety.

[0024] 2. The wind tunnel body of the present invention mainly adopts a vertical double-return wind tunnel configuration. Compared with the single-return structure of the traditional wind tunnel, the double-return wind tunnel can effectively reduce the size of each section of the wind tunnel and reduce the overall cost of the wind tunnel;

[0025] 3. The power system of the present invention adjusts the speed through the variable frequency motor, which can meet the requirements of the wind speed flow field in each functional section. The refrigeration system of the present invention cools the airflow of the wind tunnel, ensuring a comfortable temperature for the parachutists during the test section, and can ensure the continuous operation of the wind tunnel for a long time, effectively improving the training efficiency;

[0026] 4. The present invention integrates the characteristics of acoustic wind tunnels, installs sound-absorbing cotton in the tunnel body and lines the inner wall with sound-absorbing orifice plates, which fully reduces the flight cabin noise;

[0027] 5. The transparent design of the tempered glass layer and the acrylic plate of the present invention facilitates observation, expands the training content and function of the skydiving wind tunnel, and the upper and lower parts can communicate in real time through the video intercom equipment. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] Figure 1 It is a structural schematic diagram of a double-reflow, low-vibration, temperature-controllable, high-efficiency parachuting training anechoic wind tunnel;

[0029] Figure 2 This is the coordination and installation diagram of the wind tunnel body;

[0030] Figure 3 This is a schematic diagram of the flight cabin structure;

[0031] Figure 4 This is the installation diagram of the protective net and the flight cabin;

[0032] Figure 5 This is the coordination and installation drawing of the protective net and the flight cabin steel structure frame;

[0033] Figure 6 yes Figure 5 An enlarged view of point 1;

[0034] Figure 7 is a schematic diagram of the structure of the first diffusion section;

[0035] Figure 8 It is a partial structural schematic diagram of the vertical reflux section;

[0036] Fig. 9 It is a structural diagram of the independent foundation tower of the power section;

[0037] Fig.10 It is the working principle diagram of the refrigeration system;

[0038] Fig.11 It is the working principle diagram of the monitoring system.

[0039] In the figure: 1- wind tunnel body, 2- power system, 3- refrigeration system, 1-1- flight cabin, 1-2- first diffusion section, 1-3- first corner section, 1-4- square to round section, 1-5- power section, 1-6- round to square section, 1-7- second corner section, 1-8- vertical reflow section, 1-9- large angle diffusion section, 1-10- third corner section, 1-11- stable section, 1-12- horizontal contraction section, 1-13- fourth corner section, 1-14- vertical contraction section, 1- 15-independent foundation tower of power section, 111-steel structure frame of flight cabin, 112-tempered glass layer, 113-protective net, 114-lower waiting cabin, 115-embedded plate for civil engineering, 116-connecting steel beam, 117-docking claw, 1-21-steel structure frame of first diffusion section, 1-22-acrylic plate, 1-23-upper waiting cabin, 1-24-base, 1-81-concrete structure, 1-82-perforated sound-absorbing plate, 1-83-keel, 1-84-sound-absorbing cotton. DETAILED DESCRIPTION

[0040] In order to make the purpose, technical scheme and advantages of the present invention clearer, the present invention is described below by the specific embodiments shown in the accompanying drawings. However, it should be understood that these descriptions are only exemplary and are not intended to limit the scope of the present invention. In addition, in the following description, the description of well-known structures and technologies is omitted to avoid unnecessary confusion of the concept of the present invention.

[0041] The connection mentioned in the present invention is divided into fixed connection and detachable connection. The fixed connection is a non-detachable connection including but not limited to conventional fixed connection methods such as folding connection, rivet connection, bonding connection and welding connection. The detachable connection includes but not limited to conventional detachable methods such as threaded connection, snap connection, pin connection and hinge connection. When the specific connection method is not clearly defined, it is assumed that at least one connection method can always be found in the existing connection methods to achieve the function. Those skilled in the art can choose according to their needs. For example: a fixed connection is selected as a welding connection, and a detachable connection is selected as a hinge connection.

[0042] Specific implementation method 1: Combination Figure 1-Figure 11 The present embodiment is described as follows: a double-reflow low-vibration temperature-controllable high-efficiency parachuting training anechoic wind tunnel in the present embodiment comprises a wind tunnel body 1, a power system 2 and a refrigeration system 3, wherein the power system 2 and the refrigeration system 3 are both connected to the interior of the wind tunnel body 1, such as Figure 1 As shown;

[0043] The wind tunnel body 1 comprises a flight cabin 1-1, a first diffusion section 1-2, a first corner section 1-3, a square-to-round section 1-4, a power section 1-5, a round-to-square section 1-6, a second corner section 1-7, a vertical reflux section 1-8, a large-angle diffusion section 1-9, a third corner section 1-10, a stabilizing section 1-11, a horizontal contraction section 1-12, a fourth corner section 1-13, a vertical contraction section 1-14, and an independent foundation tower 1-15 for the power section. The first diffusion section 1-2 is installed on the top of the flight cabin 1-1, the first diffusion section 1-2 is connected to the power section 1-5 through the first corner section 1-3, and the power section 1-5 is connected to the round-to-square section 1-6 is connected to the second corner section 1-7, the second corner section 1-7 is connected to the top of the vertical return flow section 1-8, the bottom of the vertical return flow section 1-8 is connected to the third corner section 1-10 through the large-angle diffusion section 1-9, the third corner section 1-10 is connected to the horizontal contraction section 1-12 through the stabilizing section 1-11, the horizontal contraction section 1-12 is connected to the vertical contraction section 1-14 through the fourth corner section 1-13, the top of the vertical contraction section 1-14 is connected to the bottom of the flight cabin 1-1, and the power section 1-5 is supported by the ground through the power section independent foundation tower 1-15; each section of the wind tunnel body 1 constitutes a closed circulation passage, such as Figure 2 and 3 shown.

[0044] The wind tunnel body 1 is provided with a plurality of sampling points. Each sampling point uses a pneumatic pump to send the extracted gas sample through a water vapor filter and a flow meter, and then sends it to the detector for detection. That is, compressed air is used as the sampling power to form a negative pressure in the pneumatic pump, and the gas in the wind tunnel is extracted through a sampling Teflon tube, a water vapor filter, and a flow meter to the detector for detection. When the detector detects that the gas sample extracted from any sampling point is unqualified, that is, the concentration of the relevant gas detected exceeds the standard, the monitoring system sends a signal to the sound and light alarm lamp to give a real-time alarm, remind the staff, and send the signal value to the DCS system distributed control system, which can realize real-time monitoring, curve query, historical record query and other functions. The monitoring system uses PLC to control multiple groups of sampling points for cyclic sampling.

[0045] The power system 2 is installed in the power section 1-5, or is directly connected to the power section 1-5, so as to adjust the wind speed in the wind tunnel body 1 to provide the flight cabin 1-1 with the wind speed required for the test.

[0046] The power system 2 is a wind speed adjustment device.

[0047] The preferred technical solution is that the power system 2 of this embodiment is mainly composed of an axial flow fan and a frequency conversion control cabinet. The axial flow fan and the frequency conversion control cabinet are electrically connected, and the air outlet of the axial flow fan is connected to the wind tunnel body 1. The working principle of the power system 2 is to compress and accelerate the airflow through the axial flow fan, and realize continuous adjustable wind speed through frequency conversion control. The function of the power system is to provide the kinetic energy required for the wind tunnel airflow, and realize wind speed frequency conversion control through the frequency conversion control cabinet, which is reflected in the continuous adjustable wind speed at the flight cabin 1-1, providing the flight cabin 1-1 with the wind speed required for the test.

[0048] The refrigeration system 3 includes a wind tunnel heat exchanger, which is installed in the wind tunnel body 1, or directly connected to the wind tunnel body 1, to adjust the temperature in the wind tunnel body 1 to provide the flight cabin 1-1 with the required temperature for the test. At present, domestic skydiving wind tunnels do not have a special refrigeration system heat exchanger, but only use corner guide vanes and ventilation windows to discharge heat. After long-term operation, the temperature in the flight cabin is too high, affecting the flight experience and training efficiency. This embodiment has a separate refrigeration system heat exchanger, which can ensure that the wind tunnel can run continuously for more than 5 hours. The flight cabin temperature control range is: 20~25℃, which can effectively improve the training efficiency.

[0049] The preferred technical solution, the refrigeration system 3 of this embodiment also includes a water cooling unit, a cooling water tower, a cooler, a cooling water pump, a valve instrument system and a piping system. During parachuting training, the cooling water provided by the water cooling unit is powered by the cooling water pump, and the cooling water is transported to the wind tunnel heat exchanger. The wind tunnel heat exchanger is installed in the wind tunnel heat exchange section 1-11. The air in the wind tunnel body 1 exchanges heat in the wind tunnel heat exchanger 1-11 to reduce the temperature of the air in the wind tunnel body 1. The flow rate and pressure in the pipeline are monitored by a flow meter and a pressure transmitter. The mixing water and return water of the wind tunnel heat exchanger are mixed through the mixed water temperature control circuit in the pipeline, and the water temperature at the water inlet of the cooler is adjusted to achieve temperature accuracy control of the cooler. The temperature control accuracy is ±2°C.

[0050] The flight cabin 1-1 includes a flight cabin steel structure frame 111, a tempered glass layer 112, a protective net 113, a lower waiting cabin 114, a civil engineering embedded plate 115, a connecting steel beam 116 and a docking claw 117. The flight cabin steel structure frame 111 is surrounded by the civil engineering embedded plate 115, and the flight cabin steel structure frame 111 is welded and fixedly connected to the civil engineering embedded plate 115 around the flight cabin steel structure frame 111 by connecting the steel beam 116. The flight cabin steel structure frame 111 is provided with a tempered glass layer 112 inside. The flight cabin steel structure frame 111 is enclosed by a hollow flight chamber, and the tempered glass layer 112 is bolted to the flight cabin steel structure frame 111 through a docking claw 117. A lower waiting cabin 114 is provided at the bottom of the flight cabin steel structure frame 111. The lower waiting cabin 114 is provided with a flight cabin entrance. A protective net 113 is fixedly installed on the flight cabin steel structure frame 111 at the bottom of the lower waiting cabin 114. The protective net 113 has two layers and is made of stainless steel. The protective net 113 is connected to the base of the flight cabin steel structure frame 111 by bolts. Figure 3 shown.

[0051] The flight cabin 1-1 described in this embodiment has a diameter of 4.3m and a height of 10m. Personnel perform parachute posture training here. The flight cabin steel structure frame 111 is welded by rectangular steel pipes, and the rectangular pipes are evenly arranged along the circumference. The walls and ceiling of the lower waiting cabin 114 are made of a combination of tempered glass and steel structure keels, and the glass curtain wall and the keel are connected by docking claws.

[0052] The first diffusion section 1-2 includes a first diffusion section steel structure frame 1-21, an acrylic plate 1-22, an upper waiting cabin 1-23 and a base 1-24. The acrylic plate 1-22 is arranged inside the first diffusion section steel structure frame 1-21 by bolts, and the interior of the acrylic plate 1-22 forms a hollow chamber. The base 1-24 is arranged at the bottom of the first diffusion section steel structure frame 1-21, and the base 1-24 is fixedly connected to the flight cabin 1-1. The upper waiting cabin 1-23 is arranged on the top of the first diffusion section steel structure frame 1-21, and the upper waiting cabin 1-23 is provided with a diffusion section entrance.

[0053] The inlet cross-sectional dimensions of the first diffusion section 1-2 described in this embodiment are 4.3m in diameter, 6.6m×6m in outlet cross-sectional dimensions, and 12m in height. It provides space for airflow diffusion in the flight cabin 1-1. The first diffusion section steel structure frame 1-21 is welded from square tubes. The upper waiting cabin 1-23 has the same structure as the lower waiting cabin 114. The walls and ceiling of the upper waiting cabin 1-23 are made of a combination of tempered glass and steel structure keels. The tempered glass curtain wall and the keel are connected by docking claws. In addition, electric doors are provided on the upper waiting cabin 1-23, the lower waiting cabin 114, and the side walls of the first diffusion section 1-2, which adds a new training mode to the parachuting wind tunnel, that is, the present invention has the function of parachuting from the first diffusion section 1-2.

[0054] The first corner section 1-3 described in this embodiment has an inlet cross-sectional size of 6.6×6m, an outlet cross-sectional size of 6.6m×3m, a corner radius of 0.6m, and 15 guide vanes arranged inside. Its function is to provide airflow steering and ensure the first turn of the aerodynamic circuit of the wind tunnel. The guide vanes arranged inside are arc plate guide vanes. Since the guide vanes of the first corner section 1-3 are relatively high and thin, a connecting plate is arranged in the middle of the guide vanes to increase the overall rigidity, and the two ends of the guide vanes at the corners are welded to the upper and lower walls of the first corner section 1-3.

[0055] The square-to-circular section 1-4 described in this embodiment has an inlet cross-sectional size of 3.3×3m and an outlet cross-sectional size of φ3m, and serves as a transition connecting the first corner section 1-3 and the power section 1-5.

[0056] The circular cross-section of the power section 1-5 described in this embodiment has a diameter of φ3m, which provides installation space for the axial flow fan of the power system. An independent power section foundation tower 1-15 is provided underneath, which does not share the same foundation with other sections of the wind tunnel body 1. The power section 1-5 is connected to the front and rear sections by bolts.

[0057] The inlet cross-sectional dimension of the round-to-square section 1-6 described in this embodiment is φ3m, and the outlet cross-sectional dimension is 3.3×3m, and it serves as a transition connecting the power section 1-5 and the second corner section 1-7.

[0058] The inlet cross-sectional dimensions of the second corner section 1-7 described in this embodiment are 6.6×3m, the outlet cross-sectional dimensions are 6.6×3m, the corner radius is 0.6m, and the number of guide vanes arranged inside is 11. Its function is to provide airflow steering and ensure the second turn of the aerodynamic circuit of the wind tunnel. The guide vanes arranged inside are arc plate guide vanes. Since the guide vanes of the second corner section 1-7 are relatively high and thin, a connecting plate is arranged in the middle of the guide vanes to increase the overall rigidity. The two ends of the guide vanes of the second corner section 1-7 are welded to the upper and lower walls of the second corner section 1-7.

[0059] The outer layer of the vertical return section 1-8 is a concrete structure 1-81, the flow channel surface of the inner layer is a perforated sound-absorbing plate 1-82, and a keel 1-83 is arranged between the inner layer and the outer layer, and is filled with sound-absorbing cotton 1-84.

[0060] The vertical reflow section 1-8 described in this embodiment has an inlet cross-sectional size of 6.6×3m, an outlet cross-sectional size of 9.3×4.3m, and a length of 20m. It is arranged after the outlet of the second corner section 1-7, and diffuses the air pressure and reduces the wind speed through the cross-sectional size, thereby reducing the reflow loss of the entire wind tunnel. In order to increase the structural stability, the outer layer of the vertical reflow section 1-8 is a concrete structure 1-81. A keel is made on the concrete structure 1-81, and sound-absorbing cotton is installed inside. The flow channel surface adopts a perforated sound-absorbing plate 1-82, which can effectively reduce the aerodynamic noise of the wind tunnel.

[0061] The large-angle diffuser section 1-9 described in this embodiment has an inlet cross-sectional size of 9.3×4.3m, an outlet cross-sectional size of 10×5m, and a length of 2.85m, and serves to connect the vertical return section 1-8 and the third corner section 1-10. In order to increase the structural stability, the large-angle diffuser section 1-9 is made of concrete. Like the vertical return section 1-8, a keel is made on the inner concrete layer of the inner layer, sound-absorbing cotton is installed inside, and a perforated sound-absorbing plate is used on the flow channel surface, which can effectively reduce the aerodynamic noise of the wind tunnel.

[0062] The third corner section 1-10 described in this embodiment has an inlet cross-sectional size of 10×5m, an outlet cross-sectional size of 10×5m, a corner radius of 0.75m, and 15 guide vanes arranged inside. Its function is to provide airflow steering to ensure the third turn of the pneumatic circuit of the wind tunnel. The guide vanes arranged inside are arc plate guide vanes. Since the third corner section 1-10 is relatively high and thin, a connecting plate is arranged in the middle of the guide vanes to increase the overall rigidity. The two ends of the guide vanes of the third corner section 1-10 are welded to the upper and lower walls of the third corner section 1-10. The third corner section 1-10 is made of concrete. Like the vertical return section 1-8, a keel is made on the inner concrete layer of the inner layer, sound-absorbing cotton is installed inside, and a perforated sound-absorbing perforated plate is used on the flow channel surface, which can effectively reduce the aerodynamic noise of the wind tunnel.

[0063] The heat exchanger section 1-11 described in this embodiment has an inlet cross-sectional size of 10×5m, an outlet cross-sectional size of 10×5m, and a length of 5m. The wind tunnel heat exchanger with a refrigeration system 3 installed inside, the coolant flowing inside the wind tunnel heat exchanger can exchange heat with the airflow passing outside it, cool down the gas in the wind tunnel, have temperature control capabilities, and provide the required temperature environment for the flight section. This section is made of concrete. Outside the wind tunnel heat exchanger installation area, like the vertical return section 1-8, a keel is made on the inner concrete layer of the inner layer, sound-absorbing cotton is installed inside, and the flow channel surface uses a perforated sound-absorbing perforated plate, which can effectively reduce the aerodynamic noise of the wind tunnel.

[0064] The flat contraction section 1-12 described in this embodiment has an inlet cross-sectional size of 10×5m, an outlet cross-sectional size of 6×3m, and a length of 4.7m. Through the contraction of the aperture, the low-speed airflow is accelerated for the first time, and more importantly, the height of the wind tunnel can be effectively reduced, thereby reducing the construction cost. This section is made of concrete. Like the vertical reflow section 1-8, a keel is made on the inner concrete layer of the inner layer, sound-absorbing cotton is installed inside, and a perforated sound-absorbing plate is used on the flow channel surface, which can effectively reduce the aerodynamic noise of the wind tunnel.

[0065] The fourth corner section 1-13 described in this embodiment has an inlet cross-sectional size of 6×3m, an outlet cross-sectional size of 6×3m, a corner radius of 0.4m, and 15 guide vanes arranged inside. Its function is to provide airflow steering and ensure the fourth turn of the pneumatic circuit of the wind tunnel. The guide vanes arranged inside are arc plate guide vanes. Since the corner guide vanes are relatively high and thin, a connecting plate is arranged in the middle of the guide vanes to increase the overall rigidity. The two ends of the corner guide vanes are welded to the upper and lower walls of the corner section. This section is made of concrete. Like the vertical return section 1-8, a keel is made on the inner concrete layer of the inner layer, sound-absorbing cotton is installed inside, and a perforated sound-absorbing perforated plate is used on the flow channel surface, which can effectively reduce the aerodynamic noise of the wind tunnel.

[0066] The vertical contraction section 1-14 described in this embodiment has an inlet cross-sectional size of 6×3m, an outlet cross-sectional size of φ4.3m, and a length of 3.95m. Through the contraction of the aperture, the low-speed airflow is accelerated for the second time, thereby reaching the wind speed required in the test section. It is made of steel structure and is welded to the embedded plate of the inner concrete layer of the fourth corner section 1-13.

[0067] The power section independent foundation tower 1-15 described in this embodiment is composed of concrete columns, horizontal beams and inclined beams. The power section independent foundation tower 1-15 adopts a pile foundation to avoid rigid contact with the concrete raft foundation of the wind tunnel body 1.

[0068] At present, the domestic parachuting wind tunnels do not consider the silencing of the wind tunnel circuit, which makes the noise outside the wind tunnel flight cabin too loud, which is not conducive to on-site communication and instructors' guidance of trainees. This implementation method combines the characteristics of acoustic wind tunnels, installs sound-absorbing cotton in the cave body and lines the inner wall with silencing perforated plates, which fully reduces the flight cabin noise.

[0069] This embodiment provides the function of parachuting from the first diffusion section 1-2, and the first diffusion section 1-2 uses a transparent acrylic plate for easy observation. The current skydiving wind tunnel only has the function of training by blowing upward from the test section, and cannot simulate the process of skydiving from a high altitude, and the function is relatively simple. This embodiment sets an upper waiting cabin 1-23 in the first diffusion section 1-2, which can complete the simulation training of high-altitude skydiving, and the first diffusion section 1-2 uses a transparent acrylic plate for easy observation, which further expands the training content and function of the skydiving wind tunnel, and the upper and lower parts can communicate in real time through video intercom equipment;

[0070] Generally, the power system of a skydiving wind tunnel is directly placed on the roof of an annex building or the vertical return section of the tunnel body, which will cause part of the vibration to be transmitted to the tunnel body or the skydiving area, affecting the skydiving experience and equipment safety. This embodiment uses a power section independent foundation tower 1-15 to carry the power system. The power section independent foundation tower 1-15 uses a pile foundation and is separated from the wind tunnel body concrete raft foundation to form an independent foundation, thereby improving the stability and vibration isolation capability of the system;

[0071] The inside of the parachuting wind tunnel is a closed space. If harmful gases enter the tunnel, it will endanger the safety of personnel. The monitoring system of this embodiment is provided with a harmful gas monitoring function to ensure the personal safety of the training personnel.

[0072] It should be noted that in the above embodiments, as long as the technical solutions are not contradictory, they can be arranged and combined, and those skilled in the art can exhaust all possibilities based on the mathematical knowledge of arrangement and combination. Therefore, the present invention will no longer describe the technical solutions after arrangement and combination one by one, but it should be understood that the technical solutions after arrangement and combination have been disclosed by the present invention.

[0073] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. For those skilled in the art, the present invention may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A double-reflow low-vibration temperature-controllable high-efficiency parachuting training anechoic wind tunnel, characterized by: It comprises a wind tunnel body (1), a power system (2) and a refrigeration system (3), wherein the power system (2) and the refrigeration system (3) are both connected to the interior of the wind tunnel body (1); The wind tunnel body (1) comprises a flight cabin (1-1), a first diffusion section (1-2), a first corner section (1-3), a square-to-round section (1-4), a power section (1-5), a round-to-square section (1-6), a second corner section (1-7), a vertical reflow section (1-8), a large-angle diffusion section (1-9), a third corner section (1-10), a stabilizing section (1-11), a horizontal contraction section (1-12), a fourth corner section (1-13), a vertical contraction section (1-14), and an independent basic tower frame (1-15) for the power section. The first diffusion section (1-2) is installed on the top of the flight cabin (1-1). The first diffusion section (1-2) is connected to the power section (1-5) via the first corner section (1-3). The power section (1-5) is connected to the second corner section (1-7) via the round-to-square section (1-6). The second corner section (1-7) is connected to the top of the vertical reflow section (1-8). The bottom of the section (1-8) is connected to the third corner section (1-10) through the large-angle diffusion section (1-9), the third corner section (1-10) is connected to the horizontal contraction section (1-12) through the stabilization section (1-11), the horizontal contraction section (1-12) is connected to the vertical contraction section (1-14) through the fourth corner section (1-13), the top of the vertical contraction section (1-14) is connected to the bottom of the flight cabin (1-1), the power section (1-5) is supported by the ground through the power section independent foundation tower (1-15), a plurality of sampling points are arranged inside the wind tunnel body (1), each sampling point uses a pneumatic pump to extract a gas sample through a water vapor filter and a flow meter, and then sends it to a detector for detection, when the detector detects that the gas sample extracted from any sampling point is unqualified, the monitoring system sends a signal to the sound and light alarm lamp for real-time alarm, and sends the signal value to a DCS system (distributed control system); The refrigeration system (3) comprises a wind tunnel heat exchanger, which is installed in the wind tunnel body (1) or directly communicated with the wind tunnel body (1) to adjust the temperature in the wind tunnel body (1) and provide the flight cabin (1-1) with the temperature required for the test; The flight cabin (1-1) comprises a flight cabin steel structure frame (111), a tempered glass layer (112), a protective net (113), a lower waiting cabin (114), a civil engineering embedded plate (115), a connecting steel beam (116) and a docking claw (117); the flight cabin steel structure frame (111) is surrounded by civil engineering embedded plates (115), and the flight cabin steel structure frame (111) is fixedly connected to the civil engineering embedded plates (115) on the surrounding areas by connecting steel beams (116); 111) is provided with a tempered glass layer (112) inside, the tempered glass layer (112) is enclosed inside to form a hollow flight chamber, and the tempered glass layer (112) is fixedly connected to the flight cabin steel structure frame (111) through a docking claw (117), a lower waiting cabin (114) is provided at the bottom of the flight cabin steel structure frame (111), the lower waiting cabin (114) is provided with a flight cabin entrance, and a protective net (113) is fixedly installed on the flight cabin steel structure frame (111) at the bottom of the lower waiting cabin (114); The outer layer of the vertical reflow section (1-8) is a concrete structure (1-81), the flow channel surface of the inner layer is a perforated sound-absorbing plate (1-82), a keel (1-83) is arranged between the inner layer and the outer layer, and sound-absorbing cotton (1-84) is filled in the inner layer and the outer layer.

2. A double-reflow low-vibration temperature-controllable high-efficiency parachuting training anechoic wind tunnel according to claim 1, characterized in that: The power system (2) is installed in the power section (1-5), or is directly connected to the power section (1-5).

3. A double-reflow low-vibration temperature-controllable high-efficiency parachuting training anechoic wind tunnel according to claim 2, characterized in that: The power system (2) is a wind speed adjustment device.

4. A double-reflow low-vibration temperature-controllable high-efficiency parachuting training anechoic wind tunnel according to claim 3, characterized in that: The first diffusion section (1-2) comprises a first diffusion section steel structure frame (1-21), an acrylic plate (1-22), an upper waiting cabin (1-23) and a base (1-24); the first diffusion section steel structure frame (1-21) is provided with an acrylic plate (1-22) inside, the inside of the acrylic plate (1-22) forms a hollow chamber; the bottom of the first diffusion section steel structure frame (1-21) is provided with a base (1-24), the base (1-24) is fixedly connected to the flight cabin (1-1); the top of the first diffusion section steel structure frame (1-21) is provided with an upper waiting cabin (1-23), and the upper waiting cabin (1-23) is provided with a diffusion section entrance.

5. A double-reflow low-vibration temperature-controllable high-efficiency parachuting training anechoic wind tunnel according to claim 4, characterized in that: Guide vanes are arranged inside the first corner section (1-3), the second corner section (1-7), the third corner section (1-10) and the fourth corner section (1-13).

6. A double-reflow low-vibration temperature-controllable high-efficiency parachuting training anechoic wind tunnel according to claim 5, characterized in that: The power system (2) comprises an axial flow fan and a frequency conversion control cabinet. The axial flow fan and the frequency conversion control cabinet are electrically connected, and the air outlet of the axial flow fan is in communication with the wind tunnel body (1).

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