An active drag and heat reduction system with circulating jet flow

Abstract

The present invention provides an active drag and heat reduction system with a circulating jet flow, comprising an air inlet, a transmission shaft, an impeller, an impeller support plate, a nose cone device, a bellows, a one-way valve, a jet head, a first outer shell, and a second outer shell; the nose cone device, the first outer shell, and the second outer shell are sequentially connected; the air inlet is a curved structure, its outlet end is connected to the second outer shell, and its inlet end faces the direction of the cone device; the impeller is disposed within the second outer shell and connected to the transmission shaft; the impeller support plate is disposed within the first outer shell; a first gas pipeline is formed between the impeller and the second outer shell, and a second gas pipeline is formed between the slowly contracting end of the impeller support plate and the first outer shell; the air inlet, the first gas pipeline, and the second gas pipeline are connected; the bellows, the one-way valve, and the jet head are sequentially connected and disposed within the nose cone device, with the outlet end of the second gas pipeline connected to the bellows. The present invention can solve the problems of insufficient reverse jet gas source supply and control capabilities in the prior art.

Description

Technical Field

[0001] The present invention belongs to the technical field of recyclable jet systems, and in particular relates to an active drag and heat reduction system of a recyclable jet system. Background Art

[0002] When a hypersonic vehicle cruises in near-space, the nose of the vehicle experiences severe aerodynamic heating and the resulting enormous drag, known as the thermal barrier, due to the effects of shock waves and viscosity. When the vehicle flies through the air at hypersonic speeds, the oncoming flow is blocked by the vehicle, generating a bow shock wave. This shock wave further compresses the air, converting most of the airflow's kinetic energy into heat, causing the air temperature to rise sharply. On the other hand, there is the high-temperature airflow: due to viscosity, the high-temperature airflow adheres to the surface of the vehicle and rubs against it violently. When the temperature of the aircraft surface rises to a certain level, it exceeds the maximum temperature that the body material can withstand, degrading the internal performance of the aircraft and even causing damage to the aircraft structure, leading to direct damage, especially to structures such as the nose cone.

[0003] When a hypersonic aircraft maintains a speed of Mach 6.5, without a reverse jet flow, the maximum surface temperature experienced by the aircraft can reach 2200°C. Current materials are still unable to meet the thermal protection requirements for the sharp leading edges of hypersonic aircraft. Therefore, passive thermal protection alone cannot meet the application requirements of reusable hypersonic aircraft in extreme thermal environments.

[0004] In active cooling thermal protection technology, reverse jet flow, as an active and efficient cooling method, can push the shock wave at the cone tip away from heated components, improving the thermal environment and generating convective heat transfer on the cone surface. This makes it more suitable for high Mach numbers.

[0005] Traditional active flow control methods and devices mostly consist of a few different jet channel piping designs. These suffer from insufficient control capabilities, require additional energy input or carry a large amount of air source, affect the aerodynamic shape of the aircraft, and require frequent maintenance. Furthermore, these piping systems are not compatible with the new variable nose cone, making them insufficient for achieving the green development goal of sustainable and recyclable use. Therefore, the invention of a recyclable reverse jet device with strong control capabilities and no adverse effects on the aircraft's aerodynamic shape is of great significance. Summary of the Invention

[0006] The purpose of the present invention is to provide an active drag reduction and heat reduction system with a circulating jet, which does not require an additional air source. When the jet system is not started, the windward concave cavity at the front end is used for passive thermal protection. When the jet system is started, the high-speed incoming gas is first collected, and then a centrifugal mechanical supercharger is used to reduce the speed and pressurize the high-speed incoming gas. After reaching the pressure and speed required for the jet, the gas is sprayed forward through a pipeline to achieve the effect of active drag reduction and heat reduction, thereby solving the problems of insufficient reverse jet air source supply and control capabilities in the prior art.

[0007] The present invention provides an active drag and heat reduction system with a circulating jet, comprising an air inlet, a transmission shaft, an impeller, an impeller support plate, a nose cone device, a bellows, a one-way valve, a jet head, a first outer shell, and a second outer shell;

[0008] The rear end of the nose cone device is fixedly connected to the front end of the first outer shell, and the rear end of the first outer shell is fixedly connected to the front end of the second outer shell;

[0009] The air inlet is a curved structure, and its internal cross-section is an ellipse with an equal cross-sectional area; the outlet end of the air inlet is connected to the elliptical opening at the rear end of the second outer shell, and the inlet end faces the direction of the nose cone device, so as to divert the gas entering the air inlet within the air inlet and flow out in the direction of the reverse jet;

[0010] The impeller is disposed inside the second outer shell and connected to the transmission shaft. One end of the transmission shaft extends outside the second outer shell for connection to the power device. The impeller is a semi-open impeller with a slowly expanding diameter, with the largest diameter end located at the front end of the second outer shell.

[0011] The impeller support plate is a disc-shaped structure, disposed within the first outer shell and connected to the first outer shell; the impeller support plate is connected to the other end of the transmission shaft via a central groove; the impeller support plate slowly contracts toward the nose cone device, with its largest diameter end located at the rear end of the first outer shell;

[0012] The maximum diameter of the impeller support plate is slightly larger than the maximum diameter of the impeller; a first gas pipeline is formed between the impeller and the second outer shell; a second gas pipeline is formed between the slowly contracting end of the impeller support plate and the first outer shell; the air inlet duct, the first gas pipeline, and the second gas pipeline are connected; the cross-sectional area of the second gas pipeline is smaller than the cross-sectional area of the air inlet duct;

[0013] The bellows, one-way valve and jet head are arranged inside the head cone device, the gas outlet end of the second gas pipeline is connected to the bellows, and the bellows is connected to the jet head through a one-way valve, so that the gas flows from the bellows through the one-way valve and out of the jet head; the jet head is fixedly installed at the front end opening of the head cone device; the interior of the jet head is a hollow structure, which is used as a windward concave cavity when the reverse jet is not used.

[0014] Furthermore, the air intake duct is made of titanium alloy material.

[0015] Furthermore, the impeller is connected to the transmission shaft via a rectangular spline.

[0016] Furthermore, the first outer shell and the second outer shell are made of cemented carbide.

[0017] Furthermore, the bellows is made of PEEK material.

[0018] Furthermore, the one-way valve is a cylindrical structure, and the inner two sides are connected to the outer threads of the bellows and the spray head through internal threads.

[0019] Furthermore, the jet head is provided with a central jet hole with an inner diameter of 40 mm, and four circumferential jet holes with an inner diameter of 40 mm are provided around the central jet hole, and the center distance between the four circumferential jet holes is 60 mm.

[0020] Furthermore, the jet head is made of high-temperature alloy material.

[0021] Compared with the prior art, the present invention has the following beneficial effects:

[0022] 1. The present invention provides a recirculating jet device that does not require an additional gas source. When the system is started, it first collects high-speed incoming gas, then uses a centrifugal supercharger to reduce the speed and pressure of the high-speed incoming gas to reach the pressure and speed required for jetting, and then discharges it.

[0023] 2. This invention uses an impeller to achieve air pressurization. The impeller rotates via a high-speed drive shaft, and the gas flows through its blades and is compressed and discharged backward. The housing is designed to expand and contract with the internal components, leaving a very small gap between the housing and the impeller. The gas moves backward along the path, preventing backflow.

[0024] 3. The pipeline of the present invention can be used in situations where the nose cone needs to be deformed. When the nose cone needs to be deformed, the old direct connection and the pipeline design distributed on the edge of the skin can no longer be used. The corrugated pipe used can allow the pipeline to expand and contract and bend with the nose cone, and extend directly from the empty position in the middle of the nose cone without affecting its deformation function.

[0025] 4. The present invention directly opens a hole in the front of the nose cone and installs a jet head. When the jet system is not started, the jet head and the one-way valve work together to prevent high-temperature and high-pressure air from entering the device and the interior of the nose cone to cause damage. At this time, the jet head acts as a windward concave cavity for passive thermal protection. When the passive thermal protection effect is insufficient, the jet system can be turned on again.

[0026] 5. The thermal protection system of the windward cavity and the reverse jet combination of the deformable pipeline of the present invention can realize passive thermal protection of the cavity at the front end of the nose cone and active thermal protection of the internal jet with a simple structure, and overcomes the sustainability problem of the reverse jet, without the need to replace the cooling medium every time. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Figure 1 This is a structural block diagram of an active drag and heat reduction system with circulating jet flow according to the present invention.

[0028] 1-inlet duct; 2-drive shaft; 3-impeller; 4-impeller support plate; 5-nose cone device; 6-bellows; 7-one-way valve; 8-jet head; 9-first outer shell; 10-second outer shell. DETAILED DESCRIPTION

[0029] The present invention is described in detail below with reference to the various embodiments shown in the accompanying drawings, but it should be noted that these embodiments are not limitations of the present invention, and any equivalent transformations or substitutions in functions, methods, or structures made by ordinary technicians in this field based on these embodiments are all within the scope of protection of the present invention.

[0030] Ginseng Figure 1 , this embodiment provides an active drag reduction and heat reduction system with a circulating jet, comprising: an air intake duct 1, a transmission shaft 2, an impeller 3, an impeller support plate 4, a nose cone device 5, a bellows 6, a one-way valve 7, a jet head 8, a first outer shell 9, and a second outer shell 10; the rear end of the nose cone device 5 is fixedly connected to the front end of the first outer shell 9, and the rear end of the first outer shell 9 is fixedly connected to the front end of the second outer shell 10; the air intake duct 1 is a curved structure, and its internal cross-section is an ellipse with equal cross-sectional area; the outlet end of the air intake duct 1 is connected to the elliptical opening at the rear end of the second outer shell 10, and the inlet end faces the direction of the nose cone device 5, so as to make the gas entering the air intake duct 1 be diverted in the air intake duct and flow out in the direction of the reverse jet; the impeller 3 is arranged inside the second outer shell 10 and connected to the transmission shaft 2, and one end of the transmission shaft 2 extends out of the second outer shell 10 for connection to the power device; the impeller 3 is a semi-open impeller with a slowly expanding diameter, and its maximum diameter end is located at the front end of the second outer shell 10.

[0031] The impeller support plate 4 is a disc-shaped structure, which is arranged in the first outer shell 9 and connected to the first outer shell 9; the impeller support plate 4 is connected to the other end of the transmission shaft 2 through a central groove; the impeller support plate 4 slowly shrinks toward the head cone device 5, and its maximum diameter end is arranged at the rear end of the first outer shell 9; the maximum diameter of the impeller support plate 4 is slightly larger than the maximum diameter of the impeller 3, and a first gas pipeline is formed between the impeller 3 and the second outer shell 10, and a second gas pipeline is formed between the slowly shrinking end of the impeller support plate 4 and the first outer shell 9; the air inlet 1, the first gas pipeline, and the second gas pipeline are connected; the cross-sectional area of the second gas pipeline is smaller than the cross-sectional area of the air inlet 1.

[0032] The bellows 6, the one-way valve 7 and the jet head 8 are arranged inside the head cone device 5. The gas outlet end of the second gas pipeline is connected to the bellows 6, and the bellows 6 is connected to the jet head 8 through the one-way valve 7, so that the gas flows out of the jet head 8 from the bellows 6 through the one-way valve 7; the jet head 8 is fixedly installed at the front end opening of the head cone device 5; the interior of the jet head 8 is a hollow structure, which is used as a windward concave cavity when the reverse jet is not used.

[0033] Before the vehicle accelerates to high Mach, or when the thermal environment is not high enough to ablate the cavity lip, the reverse jet system can be turned off, and only the upwind cavity thermal protection is used, thus saving the reverse jet cooling medium. When the vehicle accelerates to high Mach, the reverse jet system can be turned on.

[0034] The present invention is described in further detail below.

[0035] The present invention's recirculating jet system (i.e., an active drag and heat reduction system or device for recirculating jets) can reduce the drag and temperature generated by shock waves on the nose of a hypersonic aircraft during near-space flight, or reduce the drag and temperature generated by friction between the nose and the air during high-speed racing. A variable nose cone is a new design for supersonic fighter jets. In contrast to the nose cone deformation mechanism invented by Beijing Institute of Technology, the present invention's jet system can change the jet direction as the nose cone deforms, thereby reducing aerodynamic heating and aerodynamic drag of the incoming airflow.

[0036] The active drag reduction and heat reduction system can be installed at the rear of the nose cone of the aircraft. The first shell 9 is directly connected to the nose cone, and the jet gas extends from the front end of the nose cone through a pipeline. According to the simulation results, the high temperature and resistance caused by the shock wave are mainly concentrated in the front of the nose cone, while at the rearward position of the skin, the temperature and resistance of the gas are relatively small, and the gas will become low speed and high pressure when passing through this shock wave. Therefore, the air inlet end of the air inlet 1 of the present invention is located at a position where the incoming flow is relatively gentle next to the skin, and an inwardly rotatable hole can be opened at the skin position. When the reverse jet system needs to be turned on, the hole is opened inward, and the high-speed incoming flow enters the jet device through the air inlet 1. In order to ensure that the air intake does not interfere with the flight shape of the aircraft during high-speed flight, the same air inlet is opened at both ends of the aircraft to ensure the airflow balance of the aircraft during flight.

[0037] The internal cross-section of the air inlet 1 is an ellipse with equal cross-sectional area, preventing gas from compressing or expanding. Within the air inlet 1, gas is diverted according to the duct's bends, flowing out in the direction of the counter-flow jet. Because the air inlet 1 is subject to long-term erosion by high-speed air, it is constructed from the same titanium alloy used in the aircraft's skin. Titanium alloys offer high specific strength, excellent corrosion resistance, excellent fatigue resistance, and low thermal conductivity, ensuring both strength and corrosion resistance. Once installed, the air inlet 1 will not be assembled or disassembled, so it is directly welded to the second outer shell 10 to ensure assembly strength.

[0038] The right end of the drive shaft 2, extending beyond the jet device, can be connected to a motor. This is amplified by the transmission at the input end, resulting in high-speed rotation, driving the impeller 3 on the left. Alternatively, utilizing the principle of turbocharging, an impeller could be added where the exhaust gas exits. The exhaust gas would then propel the exhaust-end impeller to rotate, which would then be connected to the drive shaft, which in turn would drive the impeller 3. A shoulder and retaining ring on the shaft secure the impeller 3. The right-end shoulder also contacts and secures the second outer housing 10 via a bearing. The shaft is made of 45CR alloy steel, which offers high strength, wear resistance, and hardenability.

[0039] Impeller 3 is a semi-open impeller with a slowly expanding diameter. It has a rear shroud but no front shroud. Eleven continuous rotating blades extend across the entire front and rear of the impeller. Air is drawn in at the impeller hub and driven by the drive shaft to rotate the impeller at high speed, forcing the gas backwards through the blades. The impeller converts its mechanical energy into pressure energy. The centrifugal force generated by the impeller's rotation forces the air at high speed into the narrow second outer shell 10. At the point closest to the impeller blades, impeller 3 is nearly tangential to the second outer shell 10, both to compress the air and to prevent backflow. In the second outer shell 10, air molecules slow down when they encounter these blades, reducing air velocity and increasing pressure, achieving a supercharging effect. Impeller 3 is connected to drive shaft 2 via a rectangular spline, which locks together in front of the impeller support plate 4. Because the impeller frequently encounters air at high speeds, it is also made of titanium alloy.

[0040] The impeller support plate 4 is a disc-shaped structure with a diameter slightly larger than the largest part of the impeller. Its function is to reduce the pipe through which the air flows, further pressurizing the gas, and the gas flows from the edge of the support plate to the rear and concentrates. The rear part of the support plate also slowly contracts with the first outer shell 9, so that the gas flows evenly after passing the front of the support plate, avoiding the gas from expanding again and generating vortexes. The impeller support plate 4 is connected and fixed to the first outer shell 9 by 4 bolts and does not participate in the internal movement of the device. Because the support plate does not participate in the rotation, it contacts the outer ring of the bearing and plays an axial fixing role on the impeller 3 and the drive shaft 2. Two grooves of different diameters are designed on the front of the support plate for the shaft and bearing to be placed. The material used for the impeller support plate 4 is a hard aluminum alloy.

[0041] The materials used for the first outer shell 9 and the second outer shell 10 are both hard aluminum alloys. The two outer shells are connected by 8 bolts. The inner surfaces of the outer shells are designed according to the size of the impeller 3 and the impeller support plate 4. As the size of the internal components expands and contracts, the inner diameter of the pipeline is reduced, and additional resistance is avoided. The first outer shell 9 is the same size as the head cone model 5, both with an outer diameter of 500mm. The inner and outer diameters of the connecting parts of the first outer shell 9 and the second outer shell 10 are also the same. As the impeller support plate 4 shrinks, the inner diameter of the first outer shell 9 also shrinks, and the cross-sectional area after shrinkage is smaller than the cross-sectional area of the air inlet 1. The outlet end of the outer shell extends a portion into the interior of the head cone device 5, and an internal thread is tapped into its inner wall to facilitate the subsequent assembly of the pipeline.

[0042] The bellows 6 is a component that connects one end of the jet head 8 and the jet device. The jet device of the present invention is mainly for assembly behind a variable nose cone, which will undergo a small range of telescopic deformation and less bending deformation movement outside the nose in order to reduce drag. In order to adapt to these deformations, the present invention uses a bellows made of PEEK (polyetheretherketone) material, which can withstand high-temperature gas of up to 300 degrees, can bend and deform, and can also expand and contract within the telescopic size of the nose cone device. External threads are provided on the outside of the left and right ends of the bellows, and the external thread on the right end is assembled with the internal thread of the pipe extending from the shell, and the external thread on the left end of the bellows will be assembled with the gas one-way valve 7.

[0043] The one-way valve 7 is a cylindrical structure with internal threads on both sides, which can be assembled with the external threads of the bellows 6 and the spray head 8. The one-way valve 7 and the spray head 8 are both located in the first joint of the head cone deformation mechanism. Both move with the first section of the head cone as a whole and do not require expansion, contraction or bending deformation. The inside of the one-way valve 7 uses a conical valve core, which is pressed against the right valve port by the force of the left spring, so the gas can only flow from the inside of the spray device to the outside. When the gas pressure is greater than the valve opening pressure, the spring is compressed and the one-way valve is turned on. When the spray device is not in use, the outside air enters from the spray head and acts on the valve core. The valve core presses against the valve port, and the gas cannot enter the inside of the spray device, ensuring the internal airtightness and protecting the safety of the internal parts. The gas passes through the one-way valve evenly and continuously. The valve body material can be selected from hard aluminum alloy or stainless steel, or the finished product can be used directly.

[0044] The jet head 8 is a component that is in direct contact with the high temperature and high pressure of the nose cone. When the reverse jet is not used, the jet head 8 can be used as a windward cavity because it is hollow inside, to passively perform thermal protection. When active thermal protection is desired, the jet device is activated, and the jet gas is finally ejected from the one-way valve 7, passing through the jet head 8 and ejected out of the nose cone. The jet head has an inner diameter of 40mm, and is surrounded by four jet holes with an inner diameter of 40mm, for a total of five jet holes, of which the center distance of the four outer holes is 60mm, because simulation has proved that the jet with this inner diameter layout has the best drag reduction and heat reduction effect. One side of the jet head 8 is tapped with an external thread, which is assembled with the one-way valve 7, and the left side is welded together with the opening of the nose cone. The jet head 8 is often exposed to high-speed and high-temperature air during flight, so it is made of high-temperature alloy material.

[0045] During the overall assembly, the jet head 8, the one-way valve 7, and the bellows 6 are first assembled together through threads. Pay attention to the assembly direction of the one-way valve 7 so that the gas flows from the bellows 7 through the one-way valve and out of the jet head 8. After the three are assembled, the jet head 8 is placed into the opening of the nose cone. When it is placed in the corresponding position, the jet head 8 is welded to the opening on the front of the nose cone to complete the fixation of the jet head 8. This prevents the gap near the jet head 8 from being damaged by the high temperature and high pressure of the machine head, and prevents the gas from entering the interior of the nose cone device and damaging the deformed parts inside the nose cone.

[0046] Thread the end of the bellows 6 to the pipe extending from the first outer shell 9 of the jet device. After the pipe is connected, weld the first outer shell 9 to the tail of the nose cone device 5 to secure the first outer shell 9 to the nose cone device 5. After the first outer shell 9 is installed, align the threaded holes of the impeller support plate 4 with the threaded holes inside the first outer shell 9, and then use bolts to secure the two together. Screw the bolts completely into the support plate to reduce the contact area with the gas.

[0047] Install the impeller 3 onto the transmission shaft 2 through the rectangular spline, press against the shaft shoulder, install the bearings, retaining rings and other shaft parts, and then place the shaft and impeller 3 together into the groove of the impeller support plate 4. The groove will press against the outer ring of the bearing but will not contact the shaft end, allowing for the storage of bearing lubricating oil.

[0048] Align the eight threaded holes in the second outer shell 10 with the eight threaded holes in the first outer shell 9 and tighten the bolts to secure the outer shells. Once assembled, place the oil retaining ring and bearing at the outer end of the shaft, holding the shaft shoulder in place. Install the bearing end cap on the outermost side of the shaft and secure it to the outside of the second outer shell 10 with four bolts, completing the axial fixation of the drive shaft 2 and impeller 3, as well as the entire jet device. Finally, align the elliptical inner diameter of the inlet duct 1 with the reserved elliptical opening in the second outer shell 10 and weld the inlet duct 1 to the second outer shell 10, completing the assembly of the entire jet device.

[0049] When the jet system is activated, the air intake located at the rear of the aircraft's nose cone rotates inward and opens, allowing gas to enter the jet assembly directly from the air inlet 1. High-speed air is fed into the hub of impeller 3, where it contacts it. As impeller 3 rotates at high speed, the gas flows backward through the blades. Centrifugal force forces the air into the narrow housing, where it is decelerated and pressurized. The gas flows through the piping between the housing and the impeller 3 and its support plate, then into the piping within the nose cone assembly. After passing through bellows 6, it pushes open one-way valve 7 and is ejected from the nose cone assembly 5 through the jet head 8, creating a reverse jet effect.

[0050] This technology can also be used to reduce drag on high-speed racing cars by using a reverse jet flow. A car engine's exhaust turbine or a high-speed electric motor drives an impeller to pressurize the high-speed gas. Specifically, the impeller and outer casing dimensions can be modified, and the nose cone can be replaced with a racing model. Alternatively, a bellows or fixed pipe can be used to deliver the jet flow in front of the car.

[0051] The active drag and heat reduction system with recirculating jet flow has the following technical effects:

[0052] 1. The present invention provides a recirculating jet device that does not require an additional gas source. When the system is started, it first collects high-speed incoming gas, then uses a centrifugal supercharger to reduce the speed and pressure of the high-speed incoming gas to reach the pressure and speed required for jetting, and then discharges it.

[0053] 2. This invention uses an impeller to achieve air pressurization. The impeller rotates via a high-speed drive shaft, and the gas flows through its blades and is compressed and discharged backward. The housing is designed to expand and contract with the internal components, leaving a very small gap between the housing and the impeller. The gas moves backward along the path, preventing backflow.

[0054] 3. The pipeline of the present invention can be used in situations where the nose cone needs to be deformed. When the nose cone needs to be deformed, the old direct connection and the pipeline design distributed on the edge of the skin can no longer be used. The corrugated pipe used can allow the pipeline to expand and contract and bend with the nose cone, and extend directly from the empty position in the middle of the nose cone without affecting its deformation function.

[0055] 4. The present invention directly opens a hole in the front of the nose cone and installs a jet head. When the jet system is not started, the jet head and the one-way valve work together to prevent high-temperature and high-pressure air from entering the device and the interior of the nose cone to cause damage. At this time, the jet head acts as a windward concave cavity for passive thermal protection. When the passive thermal protection effect is insufficient, the jet system can be turned on again.

[0056] 5. The thermal protection system of the windward cavity and the reverse jet combination of the deformable pipeline of the present invention can realize passive thermal protection of the cavity at the front end of the nose cone and active thermal protection of the internal jet with a simple structure, and overcomes the sustainability problem of the reverse jet, without the need to replace the cooling medium every time.

[0057] It will be apparent to those skilled in the art that the present invention is not limited to the details of the exemplary embodiments described above and that the invention can be embodied in other specific forms without departing from the spirit or essential characteristics of the invention. Therefore, the embodiments should be considered in all respects as illustrative and non-restrictive, and the scope of the invention is defined by the appended claims rather than the foregoing description, and it is intended that all variations that come within the meaning and range of equivalents of the claims be embraced therein.

Claims

1. An active drag and heat reduction system with circulating jet flow, characterized in that: It comprises an air inlet (1), a transmission shaft (2), an impeller (3), an impeller support plate (4), a nose cone device (5), a bellows (6), a one-way valve (7), a jet head (8), a first outer shell (9), and a second outer shell (10); The rear end of the nose cone device (5) is fixedly connected to the front end of the first outer shell (9), and the rear end of the first outer shell (9) is fixedly connected to the front end of the second outer shell (10); The air inlet (1) is a curved structure, and its internal cross-section is an ellipse with an equal cross-sectional area; the outlet end of the air inlet (1) is connected to the elliptical opening at the rear end of the second outer shell (10), and the inlet end faces the direction of the nose cone device (5), so as to make the gas entering the air inlet (1) turn inside the air inlet and flow out in the direction of the reverse jet; The impeller (3) is arranged inside the second outer shell (10) and is connected to the transmission shaft (2); one end of the transmission shaft (2) extends outside the second outer shell (10) and is used to be connected to the power device; the impeller (3) is a semi-open impeller with a slowly expanding diameter, and its maximum diameter end is located at the front end of the second outer shell (10); The impeller support plate (4) is a disc-shaped structure, arranged in the first outer shell (9) and connected to the first outer shell (9); the impeller support plate (4) is connected to the other end of the transmission shaft (2) through a central groove; the impeller support plate (4) slowly shrinks toward the head cone device (5), and its maximum diameter end is arranged at the rear end of the first outer shell (9); The maximum diameter of the impeller support plate (4) is slightly larger than the maximum diameter of the impeller (3); a first gas pipeline is formed between the impeller (3) and the second outer shell (10); a second gas pipeline is formed between the slowly contracting end of the impeller support plate (4) and the first outer shell (9); the air inlet (1), the first gas pipeline, and the second gas pipeline are in communication; the cross-sectional area of the second gas pipeline is smaller than the cross-sectional area of the air inlet (1); The bellows (6), the one-way valve (7), and the jet head (8) are arranged inside the head cone device (5); the gas outlet end of the second gas pipeline is connected to the bellows (6), and the bellows (6) is connected to the jet head (8) through the one-way valve (7), so as to allow the gas to flow out of the jet head (8) from the bellows (6) through the one-way valve (7); the jet head (8) is fixedly installed at the front end opening of the head cone device (5); the interior of the jet head (8) is a hollow structure, which is used as a windward concave cavity when the reverse jet is not used.

2. The active drag and heat reduction system with circulating jet according to claim 1 is characterized in that: The air inlet (1) is made of titanium alloy material.

3. The active drag and heat reduction system with circulating jet according to claim 1 is characterized in that: The impeller (3) is connected to the transmission shaft (2) via a rectangular spline.

4. The active drag and heat reduction system with recirculating jet flow according to claim 1, characterized in that: The first outer shell (9) and the second outer shell (10) are made of hard alloy.

5. The active drag and heat reduction system with circulating jet according to claim 1 is characterized in that: The bellows (6) is made of PEEK material.

6. The active drag and heat reduction system with recirculating jet flow according to claim 1, characterized in that: The one-way valve (7) is a cylindrical structure, and the inner two sides are connected to the outer threads of the bellows (6) and the spray head (8) through internal threads.

7. The active drag and heat reduction system with circulating jet according to claim 1 is characterized in that: The spray head (8) is provided with a central spray hole with an inner diameter of 40 mm, and four circumferential spray holes with an inner diameter of 40 mm are arranged around the central spray hole, and the center distance between the four circumferential spray holes is 60 mm.

8. The active drag and heat reduction system with circulating jet according to claim 1 is characterized in that: The jet head (8) is made of high-temperature alloy material.

Images