flying object

Abstract

A flying object having a shell (11) that separates an interior (12) of the flying object from an external environment, wherein the shell (11) of the flying object has, at least in sections, an inner wall (17) pointing toward the interior (12) and an outer wall (18) pointing toward the external environment to form at least one double-walled shell section such that a cavity is formed between the inner wall (17) and the outer wall (18), in which cavity at least one battery (20) with a plurality of battery cells for supplying electrical energy to the flying object is arranged, characterized in that the flying object has a fuselage on which lift-generating wings (10) are arranged, wherein the lift-generating wings (10) have a leading edge that has the double-walled shell section with at least one battery (20), wherein the leading edge is detachably arranged on the wing (10).

Description

[0001] The invention relates to a flying object with a shell that separates an interior of the flying object from an external environment.

[0002] Flying objects or aircraft with fixed wings generate their lift through sufficient airflow over the wing, also known as the wings or wing arrangement, which usually protrudes laterally from the fuselage. The wings or wing arrangements have an aerodynamic profile shape that ensures that a sufficiently fast flow through the surrounding air layers generates a lift force that keeps the aircraft airborne. In order to achieve such an airflow in fixed-wing aircraft at a speed that ensures that the aerodynamic profile shape of the wings generates sufficient lift, a propulsion device must be used to continuously generate propulsion for the aircraft, keeping the aircraft constantly above the minimum propulsive speed at a constant altitude.

[0003] The majority of such propulsion systems for aircraft are based on the principle of internal combustion engines or jet engines, in which propulsion is generated by burning fuel (e.g., based on fossil fuels). The disadvantage of these systems is that, in addition to the high environmental impact caused by the exhaust gases produced during fuel combustion, the required fuel must be carried throughout the entire flight, including a safety reserve, and is inherently not available indefinitely.

[0004] In solar-powered aircraft, however, the energy required for the propulsion system is provided by solar cells that convert sunlight into electrical energy. These cells are arranged on the exterior of the aircraft. Due to their flat shape, the wings are particularly suitable for the arrangement of solar cells in the form of solar panels to generate the required electrical energy. Such solar-powered aircraft also have an electrically operated propulsion system that is supplied with electrical energy provided by the conversion of sunlight into electrical energy using solar cells. The electrical energy generated by the solar cells can also be fed into an on-board electrical energy storage device if required, for example to maintain flight operations overnight.

[0005] The advantage of such solar-powered aircraft is that they don't require additional fuel, which can run out and interrupt flight operations. This allows these solar-electric aircraft to fly for extended periods (theoretically indefinitely), opening up new application possibilities. However, the electrical energy required for nighttime operation must be stored in an electrical energy storage system, so high-altitude solar platforms designed for long flight durations, in particular, must carry a significant number of batteries.

[0006] These batteries represent an essential component of sustained flight. They serve as intermediate storage for the electrical energy generated by the sun, but at the same time, they contribute the largest mass of the entire system, accounting for about 50% of the total mass.

[0007] Typically, the batteries are assembled into larger blocks and housed in the wing between the main spar and the leading edge of the wing. This placement ensures a favorable shift of the aircraft's center of gravity forward, which is particularly desirable for solar platforms. However, the relatively large individual masses per battery block have a disadvantage, which must be counteracted by a stiffened and thus heavier wing structure. If the solar platform is to suffer no performance losses, the now heavier wing structure must be counteracted with more electrical energy for propulsion. The increased energy demand, in turn, must be met with more batteries and thus more battery mass, which again leads to stiffer and therefore heavier wing structures.

[0008] US 2019 / 0 263 498 A1 discloses an aircraft in which a battery for electrical power supply is to be integrated. It is envisaged that the entire aircraft will be covered with such a battery arrangement.

[0009] US 8 967 529 B1 discloses the integration of batteries into a flying object, whereby structural components that serve to ensure the stability of the flying object are to be replaced by a battery arrangement.

[0010] A similar approach is also shown in US 2021 / 0 197 978 A1, which deals with the integration of a battery assembly into a quadcopter. The mounting brackets that attach the individual rotors to the fuselage are to be equipped with a battery assembly.

[0011] It is therefore an object of the present invention to provide an improved flying object with a battery for a battery-electric drive that takes into account the aspect of lightweight construction.

[0012] The object is achieved according to the invention with the flying object according to claim 1. Advantageous embodiments of the invention can then be found in the corresponding subclaims.

[0013] According to claim 1, a generic flying object is proposed with a shell that delimits an interior of the flying object from an external environment, in which according to the invention the shell of the flying object has, at least in sections, an inner wall pointing towards the interior and an outer wall pointing towards the external environment to form at least one double-walled shell section such that a cavity is formed between the inner wall and the outer wall, in which cavity at least one battery with a plurality of battery cells for the electrical energy supply of the flying object is arranged.

[0014] The double-walled hull section accordingly has an inner wall and an outer wall, with the outer wall preferably forming the outer flow surface. The inner wall is part of the interior cladding. The outer wall and the inner wall are spaced apart from one another such that a cavity is formed between them, which is filled by at least one battery with a plurality of battery cells. This at least one battery serves to supply electrical energy to the flying object, for example, to supply the electric drive.

[0015] This integrates the battery into the aircraft's hull, at least in sections, creating a single, integral component. The battery in the double-walled hull section thus becomes part of the aircraft's supporting structure, eliminating the need for additional support structures, as is currently common practice. It has also been shown that integrating the battery into the hull of an aircraft has a positive effect on its flight characteristics and results in optimal mass distribution.

[0016] The battery with multiple battery cells is preferably a rechargeable battery, also colloquially referred to as a rechargeable battery or accumulator. The battery can be a lithium-based battery, such as a lithium polymer battery, which allows for significant bending and considerable freedom in shaping.

[0017] According to one embodiment, it is provided that the flying object has an electric drive device which generates propulsion of the flying object by means of electrical energy, wherein the flying object is configured such that the electric drive device is supplied with electrical energy from the at least one battery arranged in the double-walled shell section.

[0018] With the aid of a control device, the supply of the electric drive device with electrical energy from the battery arranged in the double-walled shell section can be controlled in order to achieve the desired flight condition.

[0019] According to one embodiment, it is provided that the flying object has a solar cell arrangement with a plurality of solar cells which converts sunlight into electrical energy, wherein the flying object is configured such that the electrical energy converted by the solar cell arrangement is fed into the at least one battery arranged in the double-walled shell section.

[0020] In conjunction with an electric drive device, a particularly self-sufficient solar platform can be realized in which the electrical energy converted by the solar cell arrangement is fed into the at least one battery arranged in the double-walled casing section and the electric drive device is then supplied from the electrical energy stored in this battery.

[0021] According to the invention, the flying object comprises a fuselage on which lift-generating wings are arranged, wherein the lift-generating wings have a leading edge which comprises the double-walled shell section with at least one battery (20), wherein the leading edge is detachably arranged on the wing (10).

[0022] According to one embodiment, it is provided that tail units are arranged on the fuselage, wherein a double-walled shell section with at least one battery is provided at least in sections in the tail units.

[0023] It has proven particularly advantageous to locate the battery in the double-walled fuselage section near the wings or tail units, thereby achieving a particularly optimal mass distribution across the entire wing or tail unit. The wings are those elements of the aircraft that contribute significantly to generating lift. The tail units are, in particular, control surfaces such as horizontal stabilizers or vertical stabilizers.

[0024] It is particularly advantageous if the leading edge is detachably mounted on the wing. This ensures that if the leading edge is damaged, it can be replaced, thus ensuring the operational safety of the aircraft. Furthermore, a defective battery can be easily replaced by swapping the leading edge of the wing. It is conceivable that the leading edge could be modularly divided into several individual modules, allowing damaged batteries to be replaced module by module.

[0025] According to one embodiment, it is provided that the inner wall and / or the outer wall of the double-walled shell section is formed from a fiber composite material, preferably from GRP or CFRP.

[0026] The use of a fiber composite material takes into account the lightweight construction concept of such a flying object.

[0027] According to one embodiment, the flying object is a high-altitude solar platform. Such a high-altitude solar platform is designed for long flight times in the lower stratosphere (approximately 20 km altitude). Such a high-altitude solar platform typically has a very low surface load of well under 5 kg / m 2 on.

[0028] The invention is explained by way of example with reference to the accompanying figures. They show: Fig. 1 Side view of a wing, Fig. 2 Top view of the wing.

[0029] Fig. 1 and Fig. 2 show a wing 10 or a wing, which has an outer skin 11. In the interior 12 formed by the outer skin 11, the main spar 13 can be seen, which provides the necessary stability across the span of the wing 10. This spanwise stability is achieved by transverse wing ribs ( Fig.2). The wing leading edge 14 is located in front of the main spar 13, while the wing trailing edge 15 is located at the rear end of the wing 10 (not to scale).

[0030] The wing leading edge 14 is designed over the entire span in the form of a double-walled envelope section and has an inner wall 17 and an outer wall 18, between which a cavity is formed which is filled by a battery 20.

[0031] The inner wall 17 and the outer wall 18 are constructed from a fiber composite material in a shell construction, thus providing the necessary safety and stability. Such a fiber composite material can be, for example, CFRP or GFRP.

[0032] By using a lithium polymer battery, the highly curved shape of a wing's leading edge can be simulated. The cavity formed between the inner wall 17 and the outer wall 18 is almost completely filled by the battery.

[0033] Such an arrangement of the battery within the skin 11 of a wing 10 enables a particularly optimal mass distribution of the battery without the need for additional stiffening structures to secure the battery. This reduces the necessary mass input into the aircraft. List of reference symbols 10 Wing 11 Cover 12 Interior 13 Main spar 14 Wing leading edge 15 Wing trailing edge 16 wing ribs 17 Inner wall 18 Outer wall 20 battery

Claims

[1] Flying object with a shell (11) delimiting an interior (12) of the flying object from an external environment, wherein the shell (11) of the flying object has, at least in sections, an inner wall (17) pointing towards the interior (12) and an outer wall (18) pointing towards the external environment to form at least one double-walled shell section such that a cavity is formed between the inner wall (17) and the outer wall (18), in which cavity at least one battery (20) with a plurality of battery cells for the electrical energy supply of the flying object is arranged, characterized by in that the flying object has a fuselage on which lift-generating wings (10) are arranged, wherein the lift-generating wings (10) have a leading edge which has the double-walled shell section with at least one battery (20), wherein the leading edge is detachably arranged on the wing (10). [2] Flying object according to claim 1, characterized by that the flying object has an electric drive device which generates propulsion of the flying object by means of electrical energy, wherein the flying object is designed such that the electric drive device is supplied with electrical energy from the at least one battery (20) arranged in the double-walled shell section. [3] Flying object according to claim 1 or 2, characterized by in that the flying object has a solar cell arrangement with a plurality of solar cells which converts sunlight into electrical energy, wherein the flying object is configured such that the electrical energy converted by the solar cell arrangement is fed into the at least one battery (20) arranged in the double-walled shell section. [4] Flying object according to one of the preceding claims, characterized bythat tail units are arranged on the fuselage, wherein a double-walled shell section with at least one battery (20) is provided at least in sections in the tail units. [5] Flying object according to one of the preceding claims, characterized by that the inner wall (17) and / or the outer wall (18) of the double-walled shell section is formed from a fiber composite material, preferably from GRP or CFRP. [6] Flying object according to one of the preceding claims, characterized by that the flying object is a high-flying solar platform.

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