Patent Application
20250108931
This application claims the benefit of European Patent Application Number 23201041.3 filed on Sep. 29, 2023, the entire disclosure of which is incorporated herein by way of reference.
The present invention relates to a liner segment system for a frame bay of a fuel tank structure, an arrangement for a tank structure, comprising a liner segment system and an airplane comprising said liner segment system.
In aircrafts, a liner in each frame bay of the fuselage can be used as an additional protection of a tank structure for the fuel needed to operate the aircraft. In the undesired case, for example caused by malfunction of the undercarriage during takeoff and landing, that a hole in the fuselage structure leads to a fuel leakage, the liner is an additional safety barrier and covers the hole and hereby decreases the leakage rate.
To prevent corrosion caused by a liner next to the fuselage, in addition to the volume above the liner, there is an additional volume of fuel over or underneath the liner. The segments are closely connected to each other by means of profiles. This leads to the situation that within each lower frame bay a portion of unusable fuel remains within the tank and therefore a relevant portion of fuel remains unusable and unreachable for fuel pumps within the tank.
This either leads to a problem of weight due to the remaining fuel or even of fulfilling authorities' safety requirements. The total weight of the unused fuel that is unreachable for the fuel pumps at the picking points can add up to more than 350 liters, which leads to need to improve the possibility to reach the remaining fuel for the fuel pumps to address the above-mentioned problems.
It is an object to increase the usable tank volume and save weight due to reduction of remaining fuel portion for fulfillment of authority and customer requirements.
This object may be achieved by one or more embodiments of the present invention described herein.
According to one aspect a liner segment system for a frame bay of a fuel tank structure is provided. The liner segment system comprises a liner segment base body, wherein the liner segment base body is adapted to float on fuel in the fuel tank structure. The liner segment system further comprises a displacement body, wherein the displacement body is arranged next to a lowest point of the liner segment base body.
The term “adapted to float” refers to the case that the fuel tank is almost empty and the liner segment base body floats on a remaining portion of fuel within the fuel tank structure and reduces a remaining portion of fuel by displacing the fuel at the lowest point of the liner segment base body. If the tank is full or contains more than just a remaining portion of fuel, “adapted to float” refers to as a “hovering” within the fuel in the area of the lowest point of the liner segment base body.
Hence, a remaining portion of fuel within the fuel tank structure is reduced by displacing the fuel at the lowest point of the liner segment base body.
The described liner segment system is configured for a frame bay within a fuel tank structure and consists of two main components: the liner segment base body and the displacement body.
The significance of this configuration lies in its ability to efficiently manage fuel within the tank structure. By positioning the liner segment base body close to the lowest-level counterpart, the displacement of fuel at the lowest point becomes highly effective. This strategic placement optimizes the liner segment system's performance, contributing to enhanced fuel storage efficiency and management.
Hence, a concept is described to reduce the portion of remaining and therefore unusable fuel within a structural tank for the case that structural constraints are hindering the emptying of the tank.
It is proposed to position the displacement bodies in the area of trapped fuel. The displacement bodies may be limited in size by the manhole through which they will be installed.
The advantages are weight saving in case of displacement bodies are of lower density than fuel and reduction of remaining fuel portion for fulfillment of authority and customer requirements
Additional tie down structure may be necessary to keep all the displacement bodies in place and to prevent them from movement.
According to an embodiment the liner segment base body comprises an upper side and the displacement body is arranged on the upper side of the liner segment base body.
This specific arrangement carries notable implications. It serves a protective purpose by effectively shielding the displacement body from potential external impacts or wear, as it occupies the uppermost position above the liner segment base body. Furthermore, this positioning suggests a functional role in maintaining the balance and stability of the liner segment system. Placing the displacement body on top implies a top-down approach to stability, potentially aiding in the even distribution of weight across the fuel surface. This could contribute to a reduction in any tilting or instability of the liner segment system within the fuel tank. The placement of the displacement body on the upper side may also signify an efficiency aspect. It implies a close interaction between the displacement body and the liner segment base body, suggesting potential synergistic effects that enhance the system's ability to maintain balance within the fuel tank.
According to an embodiment the liner segment base body comprises a lower side and the displacement body is arranged on the lower side of the liner segment base body.
Placing the displacement body underneath the liner segment base body implies a potential role in enhancing stability by acting as a counterbalance. This positioning may be particularly beneficial for maintaining equilibrium, especially in dynamic situations, as it may lower the center of gravity of the liner segment system. Moreover, positioning the displacement body on the lower side suggests a deliberate utilization of space within the liner segment system. This could be advantageous for efficiently accommodating additional components or functionalities. Furthermore, if the displacement body is arranged underneath the liner segment base body, the weight of the liner segment base body may be sufficient to keep the displacement body at its designated place without the need for a further tie down structure.
According to an embodiment the displacement body is connected to the liner segment base body, preferably via integral construction. This configuration provides a seamless connection between the displacement body and the liner segment base body. By being intricately connected, it suggests a high degree of structural cohesion. This can lead to various advantages, including enhanced reliability and durability of the liner segment system.
The term “connected” refers to physical connection of the displacement body to the liner segment to keep the displacement body in the designated place, such that, if the fuel tank is almost empty, a remaining portion of fuel within the fuel tank structure is reduced by displacing the fuel at the lowest point of the liner segment base body. Additionally, “connected” refers to that the displacement body is held in place, the tank contains more than the minimum of fuel.
The displacement body also may be connected to the liner segment base body if the displacement body is arranged on the upper side and on the lower side of the liner segment base body.
According to an embodiment the displacement body is connected to the frame bay.
The connection to the liner segment and/or the frame bay via a tie down structure can be realized in different manners:
Bolted Mounting Brackets: The displacement body can be secured to the liner segment and/or the frame bay using bolted mounting brackets. These brackets can be designed to fit the contours of the liner segment and/or the frame bay and provide a stable anchor for the displacement body.
Adhesive Bonding: A strong aerospace-grade adhesive can be used to bond the displacement body to the liner segment and/or the frame bay.
Clamp Systems: The displacement body can be held in place using adjustable clamps that secure it against the liner segment and/or the frame bay. This allows for easy installation and removal if needed.
Straps and Harnesses: High-strength straps or harnesses can be wrapped around the displacement body and fastened to anchor points at the liner segment and/or the frame bay. This method provides flexibility in positioning the displacement body.
Rail and Track Systems: The displacement body can be mounted on a rail or track system installed inside the tank. This allows the body to be adjusted or repositioned as needed, providing versatility in different fuel management scenarios.
Magnetic mounting: If the displacement body and the liner segment and/or the frame bay are made of or include magnetic materials, strong magnets can be embedded in or attached to the body to hold it securely in place. This allows for easy installation and removal.
Suspension System: The displacement body can be suspended at the liner segment and/or the frame bay using a system of cables or wires anchored to the tank structure. This method keeps the body floating (hovering) within the fuel.
Interlocking Components: The displacement body can be designed with interlocking components that connect with complementary structures at the liner segment and/or the frame bay. This could involve a snap-fit mechanism or dovetail joints, providing a secure attachment that is also easy to assemble or disassemble.
Velcro Straps: Heavy-duty Velcro straps can be used to secure the displacement body to the liner segment and/or the frame bay. This method is particularly useful for temporary installations or where quick access is required.
Spring-Loaded Fasteners: Spring-loaded fasteners can be used to hold the displacement body against the liner segment and/or the frame bay. The tension from the springs ensures a firm attachment, but allows for some flexibility and movement within the tank.
Rotary Lock Mechanism: The displacement body can be attached using a rotary lock mechanism, where rotating the body or a locking element engages it securely with the liner segment and/or the frame bay. This provides a robust attachment that can be quickly released if necessary.
Quick-Release Pins: Quick-release pins can be used to secure the displacement body in place. These pins can be easily removed to allow for rapid detachment, making maintenance or replacement straightforward.
Threaded Fasteners: The displacement body can be attached using threaded fasteners that screw into pre-drilled holes in the liner segment and/or the frame bay. This method provides a strong and secure attachment and is commonly used in aircraft assemblies.
Embedded Hooks: Hooks embedded in the liner segment and/or the frame bay can latch onto loops or eyes on the displacement body. This method provides a simple yet effective means of securing the body, with the added benefit of easy installation.
Snap-In Modules: The displacement body can be designed as a modular component that snaps into place within pre-formed slots or channels in the liner segment and/or the frame bay. This allows for a secure and modular installation that can be easily adjusted or replaced.
The preference for integral construction implies that these two components are likely manufactured as a single, unified unit. This can streamline the production process, reduce the number of separate parts, and potentially lower manufacturing costs. It may also improve the overall robustness of the system since there are fewer points of potential weakness, such as joints or fasteners.
According to an embodiment the displacement body comprises a foam.
Foam is known for its lightweight properties, making it particularly suitable for applications where weight considerations are essential, such as within fuel tank systems.
Furthermore, foam is often chosen for its versatility and ability to absorb shocks or vibrations, which can enhance the overall robustness and resilience of the displacement body. Additionally, foam is typically resistant to moisture, which is crucial for components within fuel tank systems where contact with fuel is inevitable.
Possible options for foam may include polyurethane closed cell foam like Baysafe® 64IF80T by Covestro, Density: 80 kg/m3, with glass fiber reinforced epoxy resin system cover ABS5009J39, Thickness: 0.1 mm; and area weight: 205 g/m2.
According to an embodiment the displacement body comprises a hollow body.
The use of a hollow body for the displacement body suggests a specific structural configuration. Hollow bodies are known for their lightweight characteristics, making them well-suited for applications where minimizing weight is crucial, such as within fuel tank systems.
The hollow design also introduces the possibility of adjusting the volume of the displacement body. By altering the amount of air or other materials within the hollow space, allowing for precise control of the liner segment's behavior within the fuel tank. The hollow design may be provided by inflatable displacement bodies.
According to an embodiment the displacement body comprises at least one of a group consisting of PE, PP and PVC.
These materials are renowned for their resistance to various chemicals, making them exceptionally suitable for applications involving exposure to substances like fuel. This chemical resilience is particularly vital in a fuel tank system, ensuring that the displacement body remains robust and unaffected by contact with fuel or other substances present within the tank.
Moreover, PE, PP, and PVC possess a favorable combination of qualities, including being lightweight and durable. This combination is especially advantageous when considering the need to minimize weight, as is often the case in fuel tank applications. The lightweight nature of these materials contributes to the overall buoyancy of the liner segment system.
Furthermore, these materials are commonly employed in manufacturing processes, offering versatility in shaping and forming. This versatility can streamline the production of displacement bodies, allowing for intricate or custom designs tailored to specific needs.
According to an embodiment a liner out of aramid fiber with fluorosilicone with dissipative properties is provided.
According to an embodiment the displacement body comprises a multitude of detachable displacement sub-devices.
The displacement body may take on a unique configuration by incorporating multiple detachable displacement sub-devices. Instead of adhering to the conventional single-unit displacement body design, this approach presents a system comprised of individual, interrelated sub-devices that can be separated from each other for each frame bay or the complete tank structure.
This configuration offers several significant advantages. By allowing for the effortless addition or removal of sub-devices, this system becomes inherently adaptable. Users gain the ability to finely adjust the liner segment system to precisely match the distinct requirements of various fuel tank configurations. This adaptability to different tank sizes and layouts can substantially enhance the system's performance and efficiency.
Additionally, this configuration introduces a user-friendly maintenance. Should one of the sub-devices become damaged or require maintenance or replacement, it can be addressed individually, eliminating the need for extensive system-wide repairs or downtime. This not only reduces maintenance costs but also minimizes disruptions, ensuring that the liner segment system remains operational with minimal interruptions.
Furthermore, this approach empowers users with a high degree of customization. The individual sub-devices may be arranged in diverse configurations, thereby tailoring the system to address specific needs or to achieve precise buoyancy characteristics. This customization potential is particularly advantageous in situations where unique tank requirements or varying fuel levels must be accommodated.
According to an embodiment the sub-devices are connected in a form-fit manner.
This configuration signifies a deliberate approach to securing and aligning the sub-devices precisely. The form-fit connection implies that the sub-devices are configured in such a way that they interlock or mesh together seamlessly. This ensures a tight and secure integration, minimizing any potential movement or separation during operation.
The use of a form-fit connection enhances the overall stability and reliability of the displacement body system. It guarantees that the sub-devices work effectively functioning as a cohesive unit within the liner segment system. This can be particularly advantageous in maintaining displacement characteristics, ensuring the liner segment's reliable performance in various fuel tank conditions.
According to an embodiment the displacement body comprises a layer.
This configuration introduces an added layer of functionality to the displacement body. The layer serves as a protective shield, safeguarding the displacement body from the potentially corrosive or abrasive nature of fuel. It acts as a barrier that shields the underlying structure from wear and tear caused by prolonged exposure to fuel.
The protective layer enhances the displacement body's durability and longevity. It ensures that the displacement body can effectively continue its operation within the fuel tank structure over an extended period without succumbing to fuel-related corrosion or mechanical wear.
According to an embodiment a density of the displacement body is less than 90%, preferably less than 80%, more preferably less than 70% most preferably less than 50% of a density of a fuel to be displaced.
This density differential between the displacement body and the fuel within the tank is a crucial aspect of the design. By having a lower density than the fuel, the displacement body may effectively save weight of the liner segment of a fuel tank structure.
According to an embodiment the displacement body substantially follows the dimensions of the fuel tank structure.
This configuration involves tailoring the shape and size of the displacement body so that it effectively fits within the fuel tank, making the most of the available space. The term “substantially follows” implies that the displacement body aligns itself with the internal dimensions of the tank, ensuring a firm fit. This results in the efficient displacement of fuel throughout the entire tank. With the displacement body closely matching the tank's dimensions, it can effectively utilize the available space, thereby optimizing the tank's storage capacity. This ensures that the liner segment system contributes significantly to efficient fuel storage. Additionally, this configuration minimizes any unused space within the tank. Furthermore, the alignment with the tank's dimensions can enhance the stability and balance of the liner segment system.
According to another aspect an arrangement for a tank structure comprising a liner segment according to the above-mentioned embodiments is provided. The system further comprises a multitude of frame bays, a multitude of liner segments which is adapted to float on fuel in the tank structure. Each liner segment is adapted to float on fuel in one of the multitude of frame bays. Each liner segment comprises a liner segment base body, a multitude of connection profiles, wherein the multitude of connection profiles is adapted to connect the multitude of liner segments and the liner segment according to the above-mentioned embodiments. The system further comprises a fuel pump, wherein in the fuel pump is adapted to pump fuel out of the tank structure at fuel pump picking points. The system further comprises a displacement body, wherein the displacement body is arranged next to a lowest point of at least one of the liner segment base body, such that a remaining portion of fuel within the fuel tank structure is reduced by displacing the fuel at the lowest point of the liner segment base body.
The arrangement presented here is tailored for tank structures and comprises several key components, with a central focus on the innovative liner segment system as elaborated in previous embodiments. This liner segment system forms the cornerstone of a larger, highly efficient arrangement.
At its core, the system incorporates a multitude of frame bays, each designed to house a corresponding liner segment. These liner segments are meticulously crafted to float gracefully on the surface of the fuel contained within the tank structure. Within each liner segment, there exists a liner segment base body and an array of connection profiles. These profiles are engineered with precision to facilitate seamless connections between the individual liner segments, thereby forming a cohesive and adaptable network within the tank structure.
A critical component of the system is the fuel pump, strategically positioned to draw fuel from designated picking points within the tank structure. This pump serves as the means to evacuate fuel from the system when required, ensuring the efficient management and extraction of fuel resources.
However, the main aspect of this arrangement lies in its incorporation of a displacement body. This component is strategically positioned adjacent to the lowest point of at least one of the liner segment base bodies. This placement is thoughtfully designed to serve a vital purpose: by efficiently displacing fuel from the lowest point of the liner segment base body, it significantly reduces the volume of fuel that remains within the tank structure.
In practical terms, this system is an approach to optimizing the storage and management of fuel within tank structures. It seamlessly combines the functionality of liner segments, connection profiles, a fuel pump, and a displacement body to ensure the efficient displacement and extraction of fuel from the system. This arrangement promises enhanced fuel storage efficiency, improved fuel management, and ultimately, significant benefits in terms of resource utilization and operational cost savings.
According to an embodiment a liner segment comprises an opening, wherein the opening is configured to give access to a worker to the tank structure via the opening, and wherein the displacement body is configured to be movable inside the tank structure via the opening.
This embodiment introduces a remarkable feature where a worker can enter the tank structure directly through the liner segment, utilizing the dedicated opening. This access point serves as a gateway for inspection, maintenance, or any necessary work within the tank structure.
The mobility of the displacement body within the tank structure via the opening is a noteworthy design aspect. It implies that the displacement body can be adjusted or repositioned within the tank structure without requiring the removal or disassembly of the entire liner segment system. This feature streamlines the process of fine-tuning or servicing the displacement body, contributing to efficient maintenance practices.
According to an aspect an airplane comprises a liner segment according to above mentioned embodiments.
This offers a significantly improved fuel efficiency for the airplane. The liner segment system's innate capacity to maximize fuel storage within tank structures becomes instrumental in reducing fuel consumption, a pivotal factor in aviation for controlling operational costs and addressing environmental concerns.
Furthermore, the enhanced fuel management and displacement capabilities of the liner segment system contribute to more stable flight conditions. In aviation, the system's capabilities can lead to heightened safety levels for both passengers and crew.
Moreover, the liner segment system's ease of maintenance and adjustment, as underscored in previous embodiments, plays a pivotal role in minimizing aircraft downtime for maintenance purposes. This streamlined maintenance process directly impacts the aircraft's operational availability, enhancing overall cost-effectiveness.
Within the framework of a patent application, it is imperative to elucidate how the liner segment system is meticulously adapted for aerospace applications. Describe how it effectively addresses the unique challenges and prerequisites of aviation, and emphasize the prospective advantages concerning fuel efficiency, safety, and maintenance. This serves to illustrate how the integration of this technology not only aligns with the rigorous demands of the aviation industry but also elevates the performance and functionality of airplanes.
The illustrations in the figures are schematic and not to scale. If the same reference signs are used in different figures in the following description of the figures, they designate identical or similar elements. However, identical or similar elements can also be designated by different reference symbols.
The liner segment base body 12 is configured to remain afloat on the fuel contained within the fuel tank structure 22. This ensures that the liner segment system effectively utilizes the available space within the tank.
The system 10 includes a displacement body 14 strategically positioned in close proximity to the lowest point of the liner segment base body 12. This positioning is crucial for optimizing the system's primary function. By efficiently displacing fuel at the lowest point of the liner segment base body 12, the displacement body 14 significantly reduces the volume of fuel that remains within the fuel tank structure. This strategic placement contributes to improved fuel storage efficiency.
The liner segment base body 12 comprises not only an upper side but also a lower side. The displacement body 14 is ingeniously arranged on the lower side of the liner segment base body 12. This strategic placement on the lower side of the base body 12 is crucial for optimizing the system's primary function. By efficiently displacing fuel at the lowest point of the liner segment base body 12, in consequence to the presence of the displacement body 14 on the lower side, the system significantly reduces the volume of fuel that remains within the fuel tank structure. This strategic placement contributes to improved fuel storage efficiency, ensuring that the liner segment system operates at its highest potential.
The displacement body 14 allows the system 10 to make more efficient use of the available space within the fuel tank structure 22. This means that a larger volume of fuel can be stored within the same tank dimensions, increasing the overall fuel capacity.
By displacing fuel from the lowest point, the displacement body 14 contributes to improved weight distribution within the tank structure 22. This can have a positive impact on the stability and balance of the vehicle, especially in applications like aviation.
With less residual fuel left in the fuel tank structure 22, the risk of fuel wastage is minimized. This is particularly important in applications where fuel is a valuable resource, as it maximizes fuel utilization and minimizes operational costs.
According to the shown embodiment liner segment system 10 comprises an opening 16, wherein the opening 16 is configured to give access to a worker to the tank structure via the opening 16, and wherein the displacement body is configured to be movable inside the tank structure via the opening 16.
Furthermore, numerous liner segment systems 10′ are provided to float upon the surface of the fuel within the tank structure. Each of these liner segment systems 10′ is tailored to match a corresponding frame bay 18. This tailored approach ensures the precise management of fuel within each designated space.
These liner segment systems 10′ each consist of liner segment base bodies 12′, serving as their foundational elements. A further component of the arrangement 50 is the fuel pump 20, strategically placed to extract fuel from predetermined fuel pump picking points within the tank structure 22.
In essence, this arrangement 50 provides a comprehensive and seamlessly integrated solution for fuel management within the tank structure 22. It leverages the synergy of multiple frame bays, tailor-made liner segment systems, connecting profiles, a fuel pump, and strategically placed displacement bodies (not shown) to optimize fuel storage, extraction, and overall resource utilization within the tank structure.
While at least one exemplary embodiment of the present invention(s) is disclosed herein, it should be understood that modifications, substitutions and alternatives may be apparent to one of ordinary skill in the art and can be made without departing from the scope of this disclosure. This disclosure is intended to cover any adaptations or variations of the exemplary embodiment(s). In addition, in this disclosure, the terms “comprise” or “comprising” do not exclude other elements or steps, the terms “a” or “one” do not exclude a plural number, and the term “or” means either or both. Furthermore, characteristics or steps which have been described may also be used in combination with other characteristics or steps and in any order unless the disclosure or context suggests otherwise. This disclosure hereby incorporates by reference the complete disclosure of any patent or application from which it claims benefit or priority.
| Number | Date | Country | Kind |
|---|---|---|---|
| 23201041.3 | Sep 2023 | EP | regional |
