Fluid propulsion system having a foldable ejector

Abstract

The ejector system is composed of a soft but strong material such as a silicon-based material, and can be pushed in and accommodated to fit within a small space when inactive, and can be expanded or extended by mechanical, pneumatic, or hydraulic means during operation. One or more embodiments of the invention disclosed herein relate to an adaptive propulsion system that operates in particular in conjunction with a pneumatic compressor or a fan.

Description

Technical Field

[0001] [Copyright Notice]

[0001] This disclosure is protected by U.S. copyright law and / or international copyright law. (c) 2023 Jetoptera, Inc. All rights reserved. Part of the disclosure of this patent document contains materials that are subject to copyright protection. The copyright owner has no objection to the facsimile reproduction by anyone of the patent document or the patent disclosure as it appears in the Patent and Trademark Office's patent file or records, but otherwise reserves all copyrights in any case.

[0002] [Claim of Priority]

[0002] This application claims the priority of U.S. Provisional Patent Application No. 63 / 340,885, filed on May 11, 2022, the content of which is incorporated herein by reference in its entirety.

Brief Description of the Drawings

[0003]

Figure 1

[0003] Illustrates an adaptive fluid propulsion system according to one embodiment.

Figure 2

[0004] Illustrates the VTOL and STOL configurations of the present invention according to one embodiment.

Figure 3

[0005] Illustrates the configuration of the present invention from VTOL to cruise according to one embodiment.

Figure 4

[0006] Illustrates the low-speed cruise configuration of the present system according to one embodiment.

Figure 5

[0007] Illustrates the high-speed cruise configuration of the present system according to one embodiment.

Figure 6

[0008] Illustrates the present system deployed on a particular aircraft according to one embodiment.

Figure 7

[0009] Illustrates the present system deployed on a particular aircraft according to one of one or more embodiments.

Figure 8

Figure 9

Figure 10

Figure 11

DETAILED DESCRIPTION OF THE INVENTION

[0004]

[0010] This provisional application is intended to describe one or more embodiments of the present invention. It should be understood that the use of absolute terms and specific quantities, such as "must" and "will", is to be construed as applicable to one or more of such embodiments, but not necessarily to all such embodiments. Thus, embodiments of the present invention may omit one or more features or functionalities described in the context of such absolute terms, or may include modifications thereof. Further, the headings in this application are for reference purposes only and shall in no way affect the meaning or interpretation of the present invention.

[0005]

[0011] One or more embodiments of the present invention disclosed herein relate particularly to an adaptive propulsion system that operates in conjunction with a compressor or fan. Instead of attempting to maximize thrust by accelerating as much air as possible to the highest speed possible, as in a typical turbofan engine, preferred embodiments of the present invention generate multiple pressurized airflows to an ejector and / or an array of simple nozzles and create forces used at all stages of flight in an exact sequence for exact mission section requirements and in conjunction with a lift generating surface that enables specific capabilities of the aircraft using the propulsion system.

[0006]

[0012] Existing VTOL and STOL propulsion systems involve rotary wings, tilt rotors, or ducted fans. The challenge for VTOL aircraft lies in the selection of the propulsion system. Helicopters are excluded from this description as the ubiquitous choice for low-speed VTOL. The propulsion systems for current high-speed V / STOL aircraft in military applications rely on large tilted rotors such as the V-22 Osprey or large fixed ducted fans such as those on the F-35 fighter jet. The challenge with the latter is that during the non-vertical flight segment, the fixed ducted fan is essentially payload weight for 99% of the mission time. This limits payload capacity, is very complex and not cost-effective for smaller manned or unmanned applications. The challenge with V22 rotors is that they require a large installation area and must be tilted very precisely, yet still limit the maximum speed due to the limitations of rotor tip speed. The history of V-22 development also shows that it has significant drawbacks that have cost many lives. There is a need for a high-speed capable VTOL propulsion system that can propel an aircraft beyond 400 knots. Most eVTOL aircraft use multiple tilted propellers, but these also suffer from high noise and speed limitations due to the nature of the propellers themselves. Many of the hundreds of proposed eVTOL platforms use multiple distributed fixed propellers for vertical takeoff and a single propulsive propeller for horizontal flight, and they have severely limited speed.

[0007]

[0013] Engineers implement advanced and costly technologies to enable the propeller to maximize its hovering efficiency, but today's smaller propellers have the drawbacks of low efficiency and high cost. The speed of cargo drones and urban air mobility flying vehicles (air taxis) is limited to low values, and propellers are noisy and inefficient at their size. One or more embodiments include a novel propulsion method that can be used without the drawbacks of propellers.

[0008]

[0014] Most aircraft may use ejectors, which are solid wall ejectors that require a large volume for accommodation and necessitate the use of airfoils with a large thickness, thereby preventing operation at high speeds without a large increase in drag-to-lift ratio (or conversely, significantly reducing the lift-to-drag performance index due to an increase in the thickness of the airfoil).

[0009]

[0015] Therefore, it is important to create an architecture that allows thin airfoil wings to coexist with the use of ejectors and thrusters that can enable fairly high speeds using airfoils that are aerodynamically suitable not only for VTOL.

[0010] [3-in-1 Propulsor]

[0016] The thruster is designed based on the principle of thrust augmentation using a special ejector and Upper Surface Blown lift augmentation. Air supply can be provided by a turbo compressor, a turbofan, or any air compressor that generates a sufficient amount of air supply at a pressure ratio of at least 1.5:1.

[0011] [Compressor]

[0017] In FIG. 1, a VTOL configuration of the present invention according to an embodiment is illustrated, and compressed air is generated by an air compressor 101. These compressors can be turbofan bypass airflows, or any type of fan or compressor that can generate a large flow at a pressure ratio of at least 1.5 with respect to ambient pressure. The air compressed by the compressor may be routed to the ejector and / or directed to the intake of the secondary nozzle or used for other purposes including being used for cooling, thrust augmentation, cabin pressurization, or other applications. Similar to a typical turbocharger compressor, the compressor may preferably have a pressure ratio of 2.5 or more during peak operation. Optionally, a valve may be present in the compressor discharge volute chamber to direct the compressed air either to an external secondary compressor or gas generator.

[0012]

[0018] The compressed air uses its own air intake 102 and supplies the air to a three-way or four-way valve 104 via a compressor outlet conduit 103. The valve serves to distribute the compressed air flow from the compressor 101 towards a series of conduits leading to various thrust generating devices.

[0013]

[0019] In one embodiment, the compressed air is directed into two conduits which distribute the flow to a series of thrusters 106 which may be referred to as fluid thrusters or ejectors aligned with the wings and flaps 108 of the aircraft. In static or light wind conditions, this motive air determines a large amount of entrained secondary air for generating thrust, but also determines the adjacent pattern of the flaps and the wall jets on the suction side of the flap 108, and is thus named upper surface blown wing or flap. Such a flow amplified 5 to 20 times the flow rate of the compressed air is ejected onto the flap at a speed of 150 - 300 mph, generating at least 50% additional lift compared to the flap in headwind conditions and resulting in a lift coefficient exceeding 10.0.

[0014]

[0020] In one embodiment, the thruster - ejectors 106 are made of a material that can be easily folded and pushed inside the wing, making the wing essentially thinner and suitable for the high speeds at which the aircraft needs to travel. These thrusters 106 only function during slow forward cruise or vertical stages using FPS when the upper surface forming the suction side of the airfoil is pulled open via a mechanism to stretch the material. Such a material can be easily pushed inside the wing at high speeds when motive air is not supplied and can recover its expanded shape when pulled open at low speeds when needed or in the case of vertical landing, and includes a silicon - based system.

[0015]

[0021] Silicon materials are known for their functionality over a wide temperature range (e.g., -50°C to 350+°C) and are thus suitable for use at altitudes up to 40,000 feet or at sea level and for receiving compressed air at pressure ratios lower than 2.5:1. These materials become rigid when powered air is fed in and foldable when inactive, making the thruster softer and designed to be easily packed small by the pressure on the upper surface (spoiler or plate) shown as element 305 in FIG. 3 or element 405 in FIG. 4, enabling the functionality of the thruster when air is supplied.

[0016]

[0022] The foldable and flexible thruster-ejectors shown in FIGS. 7 - 11 and designated 706, 806, 906, 1006, and 1106 are made of silicon-based materials and are extended to function by a mechanism that forms sidewalls on the upper, lower, left, and right of each thruster, and are extended by spacers and levers 815 (FIG. 8), 1015 (FIG. 10), and 1115 (FIG. 11) that can be pushed out by pneumatic or mechanical or hydraulic pressure, forcing the thruster to pop out of the wing. At the top of each thruster, a mechanical connection to the spoiler 705, 805, 905, 1005, or 1105 extends the thruster vertically, while the bottom of each thruster is held on the wing. The sidewall 1015 in FIG. 10 is hinged and can rotate outward when folding the thruster and pushing it into the wing. In this way, the thrusters are housed by pressure instead of rotation, or a combination thereof, occupying a much smaller space, making the wing sleeker and thinner, and thus enabling high speeds when the thrusters are housed and air bypasses the thrusters from the compressor and is fed directly into the high-speed nozzles.

[0017]

[0023] The properties of an aircraft wing are such that a specific load is required for a specific speed, and this criterion, if not met, results in a design that generates an excessive drag-to-lift characteristic. Aircraft that need to fly at high Mach numbers may require smaller wings, but accommodating large thrusters inside the wings in those situations requires a thicker airfoil, which generates more drag and may thus prevent the aircraft from functioning efficiently. For example, using a thin airfoil for high subsonic flow enables these flight conditions, but a thicker airfoil hinders that ability. In the case of VTOL aircraft, the thrusters to be utilized can enable vertical takeoff and transition to a low-speed cruise speed, and then, at higher speeds and altitudes, can be housed within smaller wings, bypassing the thrusters and instead expanding compressed air through high-speed nozzles to enable high speeds as described. In vertical landing or hovering, the opposite occurs, where the thrusters project by being extended by the upper (suction) movable surfaces of the wings and the sidewalls reinforcing them, and then compressed air is supplied through the thrusters and blown onto the upper surface of the wings.

[0018]

[0024] The compressed air is prevented from flowing towards the simple nozzle 107 and is expanded peripherally by the four-way valve 104. The configuration of the four-way valve 104 is such that it allows flow to the ejector system 106 only during takeoff, landing, or hovering, in other words, only during the vertical flight portion of the mission. The valve 104 has several positions during flight and enables high speeds by strictly blocking the flow to element 106 and allowing only the flow to element 107 during horizontal flight at higher altitudes.

[0019]

[0025] Furthermore, element 107 distributes the outflow resulting from the entrainment of air in the front, blows it against the flap and the high part of the wingspan, and generates a low-pressure area that determines better circulation. This system produces the same results as the high-lift systems or powered lift systems used in the past, except that an additional factor in lift generation is introduced by the low-pressure area in front of the thrust-enhancing ejector, and by its introduction, the power air from the compressor generates a pressure reduction in front of the thruster, thus promoting the boundary layer suction phenomenon that enables the entire wing of such a system to operate at a very high angle of attack without stall or separation. Thus, in the example where a 1 lb / s flow with a pressure ratio (PR) of 1.8 is supplied to four thrust-enhancing ejectors and a 150 mph exiting outflow blows adjacent to the upper surfaces of the airfoil and the flap, the resulting generated lift ranges from over 100% at very low speeds to over 25% at 100 knots of speed compared to a clean wing without such thruster-enhancers. The forward force is still generated by the ejector, but at the same time, additional lift is generated along with the forward thrust, effectively enhancing the lift by a factor of two compared to a "clean" wing. A clean wing can be observed in FIG. 5, where the thruster enhancer is housed within the wing, thus making the wing "cleaner", with lower drag, and a greater overall lift-to-drag ratio than when the thruster-enhancer is exposed.

[0020]

[0026] In one example, a compressor such as typically used in a turbocharger or an electric compressor operating at a maximum pressure ratio of 2.0:1 and an isentropic efficiency greater than 85% is used to generate a power air flow of 1 lb / s. In this case, the input mechanical force or electrical output required to drive the air compressor is 38 horsepower (HP). When deployed at the correct angle of incidence over the upper surface blown configuration wings on the deployed flap, the lift generated at low speeds of about 10 knots is twice that when a smooth wing is used at the same headwind speed (10 knots) but the thruster enhancer is not active or absent. This enables the aircraft to perform a very short takeoff and landing or ultimately to take off vertically into the headwind, for example, on the deck of a ship placed in the wind. A typical value of the lift obtainable in the example of a blown wing at a 10-knot headwind condition with the flap deployed is about 200 lbf for an input of 38 HP, resulting in a ratio of 5.26 lbf / HP, which is a typical value of the hovering efficiency of tilt rotors such as the V22 Osprey or helicopter as described by Maiselet al. - NASA SP-2000-4517, “The History of the XV-15 Tilt Rotor Research Aircraft: From Concept to Flight” (Bibliographic data) https: / / ntrs.nasa.gov / search.jsp?R=20000027499 (PDF) http: / / history.nasa.gov / monograph17.pdf.

[0021]

[0027] The aircraft could potentially generate a vertical thrust that is a multiple of 200 lbf in a low-speed headwind by using multiple 38 HP compressors that can be powered mechanically, electrically, or by a combination of the two power sources. Thus, a 380 HP load directed to the compressor of the auxiliary power unit, in combination with the fluid thruster enhancer and the flaps of the Brown wing, can generate a 2000 lbf vertical force by using a 10 lb / s power air flow at a pressure ratio of 1.8 to the surroundings.

[0022]

[0028] In this case, once airborne and increasing forward speed, it is advantageous for an array of thruster - enhancers or ejectors to be gradually retracted into the wing. In Figure 2, in a vertical takeoff or short - takeoff - and - landing state, all thrusters 206 (similar or identical to thruster 106) are deployed and actively receive compressor air, but once in the air, valve 204 (similar or identical to valve 104) blocks the flow to one of the branches, and after directing most of the reduced flow to the remaining thrusters still on the wing, most of it is retracted into the wing. At the same time, as the aircraft increases speed and the lift contribution of the wing due to forward speed increases, the flaps are retracted. However, the fluid thrusters still enhance lift by a combination of blowing onto the upper surface of the wing and smaller flaps, as well as by suction and boundary - layer ingestion forward, enabling the wing to operate in a state where a smooth wing would otherwise stall and at an aggressive angle of attack that cannot be achieved by a smooth wing at a given speed. The aircraft continues to accelerate during flight until the flaps are no longer needed and the speed ensures sufficient lift for flight stability and further acceleration, but the thrusters can no longer provide further acceleration, and drag and thrust cancel each other out.

[0023]

[0029] In one embodiment, the blended wing body shown in FIG. 5 takes off vertically by the deployment of all the thrusters and flaps described and illustrated in FIGS. 1-4, where it has reached a speed exceeding 100 knots but less than 300 knots, and cannot accelerate any faster by increasing the flow to the thrusters. Until that particular point, the thrusters are fully deployed and used together with the flaps, and then are gradually retracted and deactivated by the distribution valve 104, which keeps the simple expansion nozzle duct 107 inactive, stops a part of the thruster supply duct, and forces air to pass only through the remaining exposed thrusters. If no further acceleration is available, the remaining thrusters are deactivated here and the flow to them is stopped when they are stored in the wings. With the operation of storing all the thrusters in the wings, the fuselage and wings of the aircraft become more aerodynamic, and the lift-to-drag ratio increases due to the reduction in drag caused by the storage of the thrusters. Otherwise, all the air that should be supplied to the remaining thrusters is gradually fed into the duct 107, and the jet formed by the expansion of the air around it generates all the thrust of the aircraft. The sudden drop in drag determines that less thrust is required than would otherwise be generated by the thrusters that enhance thrust in all states. Therefore, the same flight state (constant speed, altitude, and attitude) can be maintained while the emerging expansion jet generates the required thrust. At this point, for a blended wing body aircraft that typically generates a lift-to-drag performance of 20-25, the aircraft requires only a small amount of thrust to further accelerate to a speed exceeding 400 knots.

[0024]

[0030] Conversely, after the mission segment is completed without using thrusters where the mission segment is hidden in the wings and fuselage at high speeds, by partially exposing the wing thrusters, the aircraft decelerates while redistributing the air from the simple expansion nozzle duct into the duct feeding thruster 506 (similar or identical to thruster 106). Further, as the speed further decreases, valve 104 opens here to supply all thrusters including those on the wings and fuselage, and the flaps are similarly deployed, generating a significant increase in thrust and lift again, enabling the aircraft to decelerate and hover and vertically land. With this approach, several of the following results are obtained.

[0025]

[0031] The thruster enhancer is deployed for vertical flight, cooperates with the flaps, and enhances the lift by at least twice that of the entrainment that does not blow air onto the upper surfaces of the flaps and wings.

[0026]

[0032] The thrusters and flaps are gradually retracted during the transition from vertical to horizontal and during accelerating flight, determining a stable and smooth flight dynamic transition and acceleration. The retraction of the flaps and thrusters needs to be carried out in conjunction with well-controlled compressor air delivery.

[0027]

[0033] Figure 5 illustrates an aircraft in a cruise state using fluid propulsion with few active thrusters on the wings. Enhancement of both lift and thrust is still achieved, and ultimately the terminal forward speed of the aircraft is achieved. At this point, an increase in the air flow from the compressor cannot generate additional thrust. That point is where the thrust enhancement no longer serves the purpose of acceleration due to an increase in drag. Therefore, the aircraft becomes more aerodynamic by directing the flow into a simple nozzle using valve 104. Figure 6 shows a high-speed configuration of an aircraft having smooth wings and fuselage, low drag, and being propelled by compressed air expanded through duct 607 (similar or identical to duct 107) and a convergent nozzle.

[0028]

[0034] Figure 6 actually shows an aircraft that has a Blended Wing Body (BWB) architecture and is propelled in a similar manner to an aircraft powered by a turbofan, where the turbofan is actually one compressor or a series of compressors 101 operating at a pressure ratio of less than 2:1, similar to a small turbofan with a fan pressure ratio of less than 2:1.

[0029]

[0035] Since the BWB aircraft has been demonstrated to produce a significant lift-to-drag ratio, it requires less forward thrust. An L / D of 25 or more can ensure high durability, significant range, and speed while also enabling vertical takeoff and landing. Such a combination does not exist in current rotary-wing aircraft.

[0030]

[0036] The onboard air compressor can be driven electrically or mechanically so as not to be constrained by the input.

[0031]

[0037] Figure 6 also shows a potential fuel tank, generator, and onboard battery that can power the aircraft and the 3-in-1 thruster.

[0032]

[0038] The 3-in-1 thruster can provide VTOL, SSTOL, STOL, or CTOL operation. In one embodiment, it hovers in Configuration 1 where the Flap Powered Surface (FPS) is deployed with flaps in the upper surface blowing system to generate sufficient vertical lift at very low or zero forward speed. In Configuration 2, it strictly provides forward thrust and partially stores the FPS thrusters within the fuselage and wings. And in the third configuration, all FPS thrusters are stored and hidden, providing a very high L / D ratio and enabling acceleration to speeds that cannot be achieved by rotary-wing aircraft.

[0033]

[0039] Figures 7 - 11 illustrate further embodiments of the present invention.

[0034]

[0040] Although the preferred embodiments of the present invention have been illustrated and described, as described above, many modifications can be made without departing from the gist and scope of the present invention. Therefore, the scope of the present invention is not limited by the disclosure of the preferred embodiments. Instead, the present invention should be completely determined by referring to the following claims.

Claims

1. An ejector system composed of a soft but strong material such as a silicon-based material, which can be pushed and accommodated to fit into a small space when not in operation, and can be expanded or extended by mechanical, pneumatic, or hydraulic means during operation.

2. All side walls of the ejector system are reinforced by a portion of the airfoil that integrates the ejector system with the airfoil during operation, and the internal conduits, primary nozzles, and secondary nozzles, as well as the diffuser of the ejector system, are made of a flexible material such as silicon or others. The ejector system according to Claim 1.

3. A propulsion system, Comprising a conduit having at least one compressor, a conduit, a four-way valve, a thrust augmentation device, and a nozzle, A compressor within the propulsion system, where the compressor defines an intake opening, and at least one outlet port is provided with a valve connected to a fluid pressurization network of the conduit, A conduit system that enables the storage of the thrust augmentation device and its exposure to the inside and outside of the respective wings and fuselage of an aircraft or a ship, A series of flaps that can be stored, tilted, and operated in conjunction with the thrust augmentation device for maximum lift and thrust generation, A converging channel communicating with the valve that enables the compressed air flow to expand into the surroundings in a preferred single direction, A series of thrust augmentation devices made of a soft but strong material, each of which includes a mixing section, a throat section, and a diffuser, thereby receiving the compressed air flow from the compressor through the fluid pressurization network and valve of the conduit and through the fluid network, using the compressed air flow as a power gas to fluidly entrain the ambient air, mix with the power gas, and discharge it at a high speed through the diffuser to generate thrust. A propulsion system comprising the above.

4. The compressor is driven by a mechanical device such as an electric motor or a turboshaft. The system according to Claim 3.

5. The fluid pressurization network communicates with the valve and can adjust the flow to a plurality of thrust augmentation devices to assist in the attitude control of the aircraft powered by the propulsion system. The system according to Claim 3.

6. A method of flying an aircraft or a hovercraft, Feed into the distribution valve, supply to several thrust enhancement devices, accelerate the compressor to maximum output, and balance the attitude of the aircraft by opening and closing a control valve that distributes compressed air to the thrust enhancement devices made of soft materials. When the compressed air is fed in, make the thrust enhancement devices operable for vertical hovering, takeoff, and landing. Position the flaps of the aircraft to receive the outflow of the thrust enhancement devices in order to enhance the amount of lift while minimizing the required forward speed of the aircraft. Position the wings of the aircraft to utilize the low-pressure region of the thrust enhancement devices so that boundary layer suction prevents stall of the wings and flaps. A method comprising the above.

7. A method for flying an aircraft or hovercraft horizontally, comprising: Accelerating or decelerating the compressor to generate more or less flow to a thrust enhancement device supplied with compressed air from the output of the compressor. Opening and closing a distribution valve to supply or block a portion of the compressed air to the thrust enhancement device in communication with the fluid network. Opening and closing a control valve that distributes the compressed air to the thrust enhancement device to expand the thrust enhancement device and control roll, yaw, and pitch. Bypassing a conduit communicating with the thrust enhancement device and opening and closing several conduits to direct the flow into a conduit leading to a propulsion nozzle mainly facing in the direction opposite to the flight direction. Mechanically compressing, folding, or pivoting the thrust enhancement device inside and outside the wings and fuselage of the aircraft. A method comprising the above.

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