An airfoil with flow control channels

Abstract

The present disclosure envisages an airfoil (100) with flow control channels The airfoil (100) comprises a leading edge (100a) and a trailing edge (100b), an upper surface (100d) configured with a contoured convex profile, a lower surface (100e) configured with a contoured concave profile and a channel network (102) configured on the lower surface (100e). The channel network (102) comprises an array of channels (102a) extending along the chord line direction. Each of the channels (102a) is configured with flow optimization contours (FOCs) (104d) which define the interior surfaces of the channels (102a). The FOCs (104d) are configured to generate localized low-pressure zones and are further configured to stabilize the boundary layer by inducing laminar flow at the entry of the channel (102a), and directing airflow reattachment at the exit of the channels (102a) to reduce the flow separation and enhance the lift-to-drag ratio across varying flight conditions.

Description

[0001] AN AIRFOIL WITH FLOW CONTROL CHANNELS

[0002] FIELD

[0003] The present disclosure relates to an airfoil with flow control channels.

[0004] DEFINITIONS

[0005] As used in the present disclosure, the following terms are generally intended to have the meaning as set forth below, except to the extent that the context in which they are used indicates otherwise.

[0006] Chord line: The expression ‘Chord line’ used in the context of this disclosure refers to but is not limited to, a straight imaginary line that extends from a leading edge to a trailing edge of an airfoil. The chord line serves as a reference line for defining the airfoil’s geometry and aerodynamic characteristics.

[0007] Flow optimization contours (FOCs): The expression ‘Flow optimization contours’ used in the context of this disclosure refers to but is not limited to, the interior surfaces of channels integrated into an airfoil. The flow optimization contours induce laminar flow at the entry of channels to stabilize the boundary layer and redirect airflow reattachment at the exit of the channels, minimizing flow separation and enhancing the lift-to-drag ratio.

[0008] Pressure differential means: The expression ‘Pressure differential means’ used in the context of this disclosure refers to but is not limited to, features, mechanisms or control systems that regulate the pressure difference between the upper surface and lower surface of an airfoil. The pressure differential means include passive elements such as wing camber, leading edge slats, trailing edge flaps, or vortex generators, which modulate the airflow to optimize aerodynamic performance.

[0009] BACKGROUND

[0010] The background information herein below relates to the present disclosure but is not necessarily prior art. Airfoils play an essential role in aircraft by generating lift and ensuring stable flight. However, conventional airfoil configuration suffers from several challenges that affect performance, efficiency, and control, particularly under varying flight conditions.

[0011] One major drawback is flow separation, which occurs when the airflow over the airfoil loses contact with the airfoil surface, particularly at higher angles of attack. The flow separation leads, to increased turbulence, increases drag, and reduces lift. In extreme cases, flow separation can lead to stall, making it harder to maintain stable flight and increasing fuel consumption. This aerodynamic inefficiency significantly impacts aircraft performance, particularly during takeoff, landing, and high-angle manoeuvres.

[0012] To mitigate flow separation, passive flow control systems such as vortex generators and winglets are commonly utilized. Vortex generators, which are small surface-mounted protrusions, create localized turbulence to energize the boundary layer and delay separation. However, while these vortex generators help sustain attached airflow, it also introduce parasitic drag, which negatively affects fuel efficiency and cruising performance. Additionally, vortex generators are fixed structures and lack the ability to adapt dynamically to changing flight conditions, such as variations in speed, altitude, or angle of attack.

[0013] Similarly, winglets, which are vertical or angled extensions at the wingtips, reduce induced drag by mitigating tip vortices. However, winglets do not address flow separation along the main body of the airfoil, leaving aerodynamic inefficiencies unresolved, particularly in regions where separation occurs along the wing span.

[0014] Further, to overcome the limitations of the passive systems, active flow control systems have been developed, incorporating synthetic jets, ailerons, flaps, slats, spoilers, and wing morphing mechanisms. The active flow control system actively manipulates airflow using actuators to inject or extract air at specific locations, thereby improving lift and reducing drag. However, the active flow control systems introduce several challenges, including increased mechanical complexity, higher maintenance requirements, and additional structural weight. The need for precise coordination of sensors and actuators makes their implementation costly, while reliance on external power sources increases energy consumption and operational complexity.

[0015] Despite advancements in both passive and active flow control systems, conventional airfoils still face a trade-off between lift enhancement, drag minimization, adaptability, and structural efficiency. Therefore, there is a felt need for an airfoil that alleviates the aforementioned drawbacks.

[0016] OBJECTS

[0017] Some of the objects of the present disclosure, which at least one embodiment herein satisfies, are as follows:

[0018] It is an object of the present disclosure to ameliorate one or more problems of the prior art or to at least provide a useful alternative.

[0019] An object of the present disclosure is to provide an airfoil with flow control channels.

[0020] Another object of the present disclosure is to provide an airfoil that mitigates flow separation.

[0021] Yet another object of the present disclosure is to provide an airfoil that reduces drag.

[0022] Still another object of the present disclosure is to provide an airfoil that facilitates a relatively improved lift to drag ratio.

[0023] Another object of the present disclosure is to provide an airfoil that operates independently of external power sources for the manipulation of fluid boundary layers.

[0024] Yet another object of the present disclosure is to provide an airfoil that is adaptable to a range of flight conditions.

[0025] Still another object of the present disclosure is to provide an airfoil that can be adapted to accommodate various airfoil shapes, sizes, different aircraft types and aeroelastic conditions.

[0026] Another object of the present disclosure is to provide an airfoil that has a simple and cost- effective configuration.

[0027] Yet another object of the present disclosure is to provide an airfoil that provides an alternative to passive flow control systems such as vortex generators and winglets, to eliminate the drawbacks of increased parasitic drag and fixed, non-adaptive structures.

[0028] Still another object of the present disclosure is to provide an airfoil that eliminates the complexity of active flow control systems. Another object of the present disclosure is to provide an airfoil that improves aerodynamic efficiency without additional structural weight.

[0029] Yet another object of the present disclosure is to provide an airfoil that minimizes wake turbulence and pressure drag.

[0030] Still another object of the present disclosure is to provide an airfoil that can reduce maintenance and operational costs.

[0031] Other objects and advantages of the present disclosure will be more apparent from the following description, which is not intended to limit the scope of the present disclosure.

[0032] SUMMARY

[0033] The present disclosure envisages an airfoil with flow control channels. The airfoil comprises a leading edge, a trailing edge, an upper surface, a lower surface, and a channel network (CN).

[0034] The leading edge and the trailing edge define a chord line therebetween.

[0035] The upper surface is configured with a contoured convex profile and extends between the leading edge and the trailing edge.

[0036] The lower surface is configured with a contoured concave profile and extends between the leading edge and the trailing edge.

[0037] The channel network (CN) is configured on an operative section of the lower surface. The channel network (CN) comprises a plurality of channels extending substantially along the longitudinal direction of the airfoil.

[0038] Each of the channels is configured with flow optimization contours (FOCs). The flow optimization contours define the interior surfaces of the channels. The flow optimization contours (FOCs) are configured to generate localized low-pressure zones along the lower surface and are further configured to stabilize the boundary layer by inducing laminar flow at the entry of the channel and directing airflow reattachment at the exit of the channels to reduce the flow separation and enhance the lift-to-drag ratio across varying flight conditions.

[0039] In an embodiment, the progressive flow optimization contours (FOCs) of the channel are configured with an entry contour section, a central contour section and an exit contour section. The entry contour section is configured near the leading edge. The entry contour section is configured to redirect incoming airflow in a controlled vortex pattern to generate localized regions of reduced pressure along the lower surface thereby increasing the differential pressure between the upper surfaces and lower surfaces to increase lift. The central contour section is configured adjacent to the entry contour section in proximity to the leading edge. The central contour section is configured to modulate airflow velocity distribution within the channel, thereby facilitating the controlled development of the boundary layer along the interior surfaces of the channels to delay flow separation. The exit contour section is configured adjacent to the central contour section in proximity to the leading edge. The exit contour section is configured with a curvature profile to enable airflow reattachment to the surrounding flow field thereby minimizing wake vortices and reducing pressure drag to optimize the lift-to-drag ratio across varying flight conditions.

[0040] In an embodiment, the exit contour section of the flow optimization contours (FOCs) is configured with a reduced radius of curvature to facilitate direct airflow reattachment to the surrounding flow field, to mitigate wake turbulence, thereby minimizing pressure drag.

[0041] In another embodiment, the channel network (CN) is configured along a mid-chord region of the lower surface. The entry contour section, the central contour section and the exit contour section of the progressive flow optimization contours (FOCs) collectively define a concave cross-sectional geometry, configured to alter the boundary layer characteristics along the lower surface to delay flow separation and maintain airflow attachment to the lower surface with the surrounding.

[0042] In yet another embodiment, the flow optimization contours (FOCs) are defined by: o at least one depth dimension configured to alter airflow velocity; o at least one width dimension configured to vary pressure distribution; and o a spacing pattern between adjacent channels, the pattern being configured based on the aerodynamic profile of the airfoil.

[0043] In still another embodiment, the channel network (CN) is configured with a pressure differential means (PDM), positioned operatively within the channel network (CN). The pressure differential means (PDM) is configured to optimize pressure gradients during varying flight regimes to enhance the lift-to-drag ratio.

[0044] In another embodiment, the channel network (CN) of the airfoil is configured to reduce the drag coefficient and increase the lift coefficient to a predefined range.

[0045] In still another embodiment, the channel network (CN) of the airfoil is configured to achieve a drag coefficient reduction in the range of 5% -20% and a lift coefficient enhancement in the range of 10%-20%.

[0046] In yet another embodiment, the channel network (CN) of the airfoil is configured to enhance the lift-to-drag ratio in a predefined range across different angles of attack.

[0047] In another embodiment, the channel network (CN) of the airfoil is configured to enhance the lift-to-drag ratio by 5%-20% across different angles of attack.

[0048] In still another embodiment, the radius of curvature of the entry contour section, the central contour section and the exit contour section of each channel is optimized within a predefined range to facilitate the generation of localized low-pressure zones along the lower surface, regulate boundary layer characteristics at the entry section, and direct airflow reattachment at the exit section.

[0049] BRIEF DESCRIPTION OF THE ACCOMPANYING DRAWING

[0050] An airfoil with flow control channels, of the present disclosure will now be described with the help of the accompanying drawing in which:

[0051] Figure 1 illustrates a front view of a conventional airfoil of a wing;

[0052] Figure 2 illustrates a front view of an airfoil of the present disclosure;

[0053] Figure 3 illustrates an isometric view of a wing with the airfoil of the present disclosure;

[0054] Figure 4 illustrates a top view of the wing with the airfoil of the present disclosure;

[0055] Figure 5 illustrates an isometric view of a straight wing with channels;

[0056] Figure 6 illustrates a side view of the straight wing with channels; Figure 7 illustrates a bottom view of the straight wing with channels;

[0057] Figure 8 illustrates a discretized view of the airfoil of the present disclosure;

[0058] Figure 9 illustrates a graph that depicts the difference in lift force generated by the conventional airfoil and the airfoil of the present disclosure at different angles of attacks;

[0059] Figure 10 illustrates a graph that depicts the difference in drag force generated by the conventional airfoil and the airfoil of the present disclosure at different angles of attacks;

[0060] Figure 11 illustrates a graph that depicts the difference in lift to drag force (Cl / Cd) generated by the conventional airfoil and the airfoil of the present disclosure at different angles of attacks;

[0061] Figure 12 illustrates a pressure plot of the conventional airfoil generated using a computational fluid dynamics modelling algorithm; and

[0062] Figure 13 illustrates a pressure plot of the airfoil generated using a computational fluid dynamics modelling algorithm.

[0063] LIST OF REFERENCE NUMERALS

[0064] 100’ Conventional airfoil

[0065] 102’ leading edge

[0066] 104’ trailing edge

[0067] 106’ upper surface

[0068] 108’ lower surface

[0069] 100 airfoil of the present disclosure

[0070] 100a leading edge

[0071] 100b trailing edge

[0072] 100c chord or chord line lOOd upper surface lOOe lower surface

[0073] 102 channel network

[0074] 102a channel

[0075] 104a entry contour section

[0076] 104b central contour section

[0077] 104c exit contour section

[0078] 104d flow optimization contours

[0079] 106 wing

[0080] A channel gap distance

[0081] B channel straight surface length

[0082] C entry contour section radius

[0083] D channel curvature radius

[0084] E exit contour section radius

[0085] X Curve line of the conventional airfoil

[0086] Y Curve line of the airfoil of the present disclosure

[0087] DETAILED DESCRIPTION

[0088] The present disclosure relates to an airfoil with integrated flow control channels, configured to enhance aerodynamic efficiency by modifying airflow characteristics, optimizing boundary layer behavior, and improving the lift-to-drag ratio. More specifically, the present disclosure pertains to an airfoil configuration that passively regulates airflow without requiring external energy sources, mechanical actuators, or additional structural modifications, thereby achieving enhanced lift generation, reduced aerodynamic drag, and increased flight stability across varying flight conditions. Embodiments are provided so as to thoroughly and fully convey the scope of the present disclosure to the person skilled in the art. Numerous details are set forth, relating to specific components, and methods, to provide a complete understanding of embodiments of the present disclosure. It will be apparent to the person skilled in the art that the details provided in the embodiments should not be construed to limit the scope of the present disclosure. In some embodiments, well-known processes, well-known apparatus structures, and well-known techniques are not described in detail.

[0089] The terminology used, in the present disclosure, is only for the purpose of explaining a particular embodiment and such terminology shall not be considered to limit the scope of the present disclosure. As used in the present disclosure, the forms "a,” "an," and "the" may be intended to include the plural forms as well, unless the context clearly suggests otherwise. The terms "comprises," "comprising," “including,” and “having,” are open ended transitional phrases and therefore specify the presence of stated features, elements, modules, units and / or components, but do not forbid the presence or addition of one or more other features, elements, components, and / or groups thereof.

[0090] When an element is referred to as being "mounted on," “engaged to,” "connected to," or "coupled to" another element, it may be directly on, engaged, connected or coupled to the other element.

[0091] The terms first, second, third, etc., should not be construed to limit the scope of the present disclosure as the aforementioned terms may be only used to distinguish one element, component, region, layer or section from another component, region, layer or section. Terms such as first, second, third etc., when used herein do not imply a specific sequence or order unless clearly suggested by the present disclosure.

[0092] Terms such as “inner,” “outer,” "beneath," "below," "lower," "above," "upper," and the like, may be used in the present disclosure to describe relationships between different elements as depicted from the figures.

[0093] Typically, conventional airfoils (100') often suffer from flow separation, a phenomenon in which airflow detaches from the airfoil surface, leading to increased turbulence, drag, and loss of lift. Flow separation becomes particularly problematic at higher angles of attack, where airflow instability can result in stall conditions, reduced aerodynamic efficiency, and increased fuel consumption. Several passive and active flow control techniques or systems have been employed to mitigate flow separation. Passive methods such as vortex generators and winglets introduce surfacemounted structures to manipulate airflow. However, the passive systems create parasitic drag, are fixed in position, and lack adaptability to dynamic flight conditions. On the other hand, active flow control systems such as synthetic jets, actuators, and boundary layer suction mechanisms actively manipulate airflow by injecting or extracting air at specific locations. While effective, but the active systems introduce complexity, increased weight, higher maintenance requirements, and additional power consumption, making them impractical for widespread application.

[0094] To overcome these limitations, the present disclosure envisages an airfoil (100) with a structurally integrated channel network (CN) (102) that passively regulates airflow, minimizes flow separation, and enhances aerodynamic efficiency. The channel network (CN) (102) is embedded within the lower surface (lOOe) of the airfoil (100), to ensure a streamlined aerodynamic profile while improving airflow attachment and boundary layer control. By leveraging flow optimization contours (FOCs) (104d) within each channel (102a), the airfoil (100) enables localized pressure regulation, controlled vortex generation, and structured airflow reattachment, resulting in reduced drag, increased lift, and improved aircraft performance.

[0095] The embodiments of the present disclosure will now be described with reference to the accompanying Figure 2 to Figure 13.

[0096] In accordance with the embodiment as illustrated in figure 2, the airfoil of the present disclosure comprises a leading edge (100a) and a trailing edge (100b), with a chord line (100c) extending between them. The upper surface (lOOd) is contoured with a convex profile, promoting pressure reduction and lift generation, while the lower surface (100c) is configured with a concave profile, which accommodates the channel network (CN) (102) for optimized airflow management.

[0097] In an embodiment, the airfoil (100) can be implemented as a symmetric or non- symmetric airfoil, making it adaptable for various aerodynamic applications, including commercial aircraft, UAVs, and wind turbine blades.

[0098] Further, the channel network (CN) (102) is configured along an operative section of the lower surface (100c) and comprises a plurality of channels (102a) extending substantially along the longitudinal direction of the airfoil (100). Each channel (102a) is characterized by flow optimization contours (FOCs) (104d), which define the internal surfaces and modulate boundary layer flow to improve aerodynamic efficiency. Figure 3 illustrates an isometric view of a wing with the airfoil (100) and figure 4 illustrates a top view of the wing with the airfoil (100).

[0099] In an embodiment, the channel network (102) includes a plurality of static, non-deformable channels (102a).

[0100] In an embodiment, each channel (102a) extends substantially along the depth of the airfoil (100).

[0101] Each channel (102a) within the channel network (CN) (102) is configured with progressive flow optimization contours (FOCs) (104d). As the airflow moves through the channel (102a), the progressive flow optimization contours (FOCs) (104d) guide the airflow along the interior surfaces of the channel (102a) and maintain airflow energy and momentum. These progressive flow optimization contours (104d) modify airflow characteristics along the lower surface (100c) of the airfoil (100) by strategically controlling pressure distribution and boundary layer characteristics. The channels (102a) enhance the aerodynamic efficiency of the airfoil (100) by reducing flow separation and improving the lift-to-drag ratio.

[0102] The flow optimization contours (104d) of each channel comprises:

[0103] • entry contour section (104a): the entry contour section (104a) is configured near the leading edge (100a), and configured to induce laminar flow to redirect incoming airflow into a controlled vortex pattern, forming localized low-pressure regions. These low- pressure zones increase the pressure difference between the upper surface (lOOd) and the lower surface (100c), which enhances lift generation. Also, due to the laminar flow, the airflow remains smooth and attached to the channel surface.

[0104] • central contour section (104b): the central contour section (104b) is configured adjacent to the entry contour section (104a), which ensures smooth airflow progression along the channel walls, maintaining boundary layer stability, and delaying flow separation. The central contour section (104b) also maintains the baseline aerodynamic profile of the airfoil (100) to support the natural progression of airflow. • exit contour section (104c): the exit contour section (104c) is configured near the trailing edge (100b), configured with a curvature profile that promotes gradual airflow reattachment, minimizing wake vortices and aerodynamic drag.

[0105] Further, each channel (102a) exhibits a dual geometry configuration. This dual-geometry configuration is configured to optimize airflow characteristics, ensuring a progressive modification of velocity, pressure distribution, and boundary layer interactions as the airflow moves through the channel (102a). The dual-geometry configuration of the channel (102a) is structured to include two distinct flow-modulating regions, each playing an essential role in achieving the aerodynamic effects of the airfoil (100).

[0106] In one embodiment, the first geometric region of the channel (102a) is located toward the entry contour section (104a), near the leading edge (100a) of the airfoil (100). This region is characterized by a pronounced curvature and a gradually constricting cross-sectional area, which serves to accelerate the incoming airflow as it enters the channel (102a). The gradual contraction of the channel width in this region results in an increase in velocity and a decrease in static pressure, thereby creating a localized low-pressure zone along the lower surface (100c) of the airfoil (100). This localized pressure reduction plays a vital role in enhancing the pressure differential between the upper surface (lOOd) and the lower surface (100c), thereby increasing lift generation. Additionally, the controlled vortex formations induced by the first geometric region of the channel (102a) facilitate boundary layer energization, which helps maintain laminar flow attachment and delays premature flow separation.

[0107] As the airflow progresses through the channel (102a), it transitions into the second geometric region, which extends toward the central contour section (104b) and the exit contour section (104c) near the trailing edge (100b). In this region, the channel width gradually expands, allowing the airflow to decelerate and regain static pressure before exiting into the surrounding flow field. The progressive expansion of the cross-section in this region is configured to promote gradual airflow reattachment, minimizing wake turbulence and pressure drag. This transition also ensures that the flow exiting the channel (102a) is smoothly reintegrated with the main flow around the airfoil (100), preventing vortex-induced aerodynamic inefficiencies.

[0108] Thus, the dual-geometry configuration of the channel (102a) is effective in optimizing the lift- to-drag ratio of the airfoil (100) by synergistically combining the benefits of localized acceleration (for enhanced lift) and controlled flow expansion (for drag reduction). Unlike conventional airfoil modifications that require external energy sources, active control systems, or additional surface attachments, the proposed dual-geometry channel design passively manipulates airflow through its intrinsic structure, offering a scalable and energy-efficient solution.

[0109] In one embodiment, the dimensions and curvature profiles of both geometric regions within the channel (102a) can be customized based on specific airfoil configuration and aerodynamic performance requirements. For instance, in applications requiring high lift at low speeds, the first geometric region may be configured with a more pronounced curvature to increase airflow acceleration, while in high-speed applications, the second geometric region may be optimized to further delay boundary layer separation.

[0110] By incorporating a dual-geometry configuration, the airfoil (100) effectively separates the traditional trade-off between increased camber and drag penalties, allowing for higher lift without proportional increases in drag. The ability to dynamically shape airflow within the channel (102a) without altering the external airfoil geometry provides a breakthrough in passive aerodynamic optimization, making the airfoil (100) suitable for diverse aerospace applications, including commercial aircraft, UAVs, and wind turbine blades.

[0111] In an embodiment, the radius of curvature of the exit contour section (104c) is optimized to further reduce wake turbulence and pressure drag, thus improving the lift-to-drag ratio.

[0112] In another embodiment, the flow optimization contours (104d) also stabilize the boundary layer. These contours (104d) sustain laminar conditions, reduce turbulence, and prevent energy losses within the boundary layer. The controlled airflow delays flow separation and prevent airflow detachment from the lower surface (100c).

[0113] In an embodiment, the airflow toward the exit of the channel (102a), and the progressive flow optimization contours (FOCs) (104d) smoothen airflow reattachment to the surrounding flow field. The channels (102a) minimize wake vortices, reduce aerodynamic drag, and enhance the overall efficiency of the airfoil (100).

[0114] In an embodiment, the entry contour section (104a), the central contour section (104b) and the exit contour section (104c) of the progressive flow optimization contours (104d) collectively define a concave cross-sectional geometry. In an embodiment, the radius of curvature of the entry contour section (104a), the central contour section (104b) and the exit contour section (104c) of each channel (102a) is optimized in a predefined range to facilitate the generation of localized low-pressure zones along the lower surface (lOOe), regulate boundary layer characteristics at the entry contour section (104a), and direct airflow reattachment at the exit section.

[0115] In another embodiment, the channel network (102) is configured along a mid-chord region of the lower surface (100c).

[0116] Further, the flow optimization contours (104d) minimize flow separation along the lower surface (100c) and significantly improve the lift-to-drag ratio. A higher lift-to-drag ratio allows the airfoil (100) to generate more lift and experience less aerodynamic resistance. The flow optimization contours (104d) improve fuel efficiency, enhance manoeuvrability, and increase stability across varying flight conditions.

[0117] In an embodiment, the flow optimization contours (FOCs) (104d) play an essential role in determining the overall aerodynamic performance of the airfoil (100) by regulating airflow behavior within each channel (102a). The configuration parameters of the FOCs (104d), including depth, width, and spacing pattern, are configured to achieve specific aerodynamic effects that contribute to flow stabilization, pressure modulation, and turbulence minimization.

[0118] • The depth dimension of the channels (102a) directly influences the airflow velocity, wherein deeper channels cause localized acceleration of the incoming airflow, thereby lowering static pressure and increasing the pressure differential between the upper surface (lOOd) and the lower surface (100c). This enhanced pressure differential leads to higher lift generation and sustained aerodynamic efficiency.

[0119] • The width dimension of each channel (102a) determines the extent of airflow expansion and contraction, which affects pressure distribution along the lower surface (100c). A narrower width intensifies localized acceleration, while a broader width enables smoother flow redistribution, thereby providing a balance between drag reduction and lift enhancement.

[0120] • The spacing pattern between adjacent channels (102a) further contributes to boundary layer regulation, ensuring that airflow remains attached over the airfoil (100) without premature separation. The spacing can be uniform or variable, depending on the aerodynamic profile of the airfoil (100), enabling customization for different flight conditions and operational requirements.

[0121] In an embodiment, the airfoil (100) integrates a pressure differential means (PDM), which is operatively positioned within the channel network (CN) (102). The PDM is configured to regulate pressure gradients dynamically, allowing the airfoil (100) to adapt to varying flight regimes, including takeoff, cruising, and landing. By modifying localized pressure zones, the PDM enhances airflow stability and ensures that the lift-to-drag ratio remains optimized across different angles of attack. The integration of the PDM within the channel network (102) provides a passive means of controlling aerodynamic forces, eliminating the need for active control mechanisms such as mechanical actuators or energy-consuming airflow injection systems. This passive adaptation allows the airfoil (100) to respond autonomously to changing flight conditions, making it highly effective for applications requiring efficient and stable aerodynamic performance without additional complexity.

[0122] In another embodiment, the dimensions of the channel (102a) including channel gap distance (A), channel straight surface length (C), channel curvature radius (D) and exit contour section radius can be varied as per desired aerodynamic performance.

[0123] In yet another embodiment, the position of channels (102a) can be changed on the airfoil (100) to modify the flow characteristics for specific aerodynamic objectives.

[0124] In an embodiment, the channel network (102) of the airfoil (100) reduces the drag coefficient and increases the lift coefficient to a predefined range. The specific configuration of the channels (102a), along with flow optimization contours (104d), minimizes flow separation and stabilizes the boundary layer along the lower surface (100c). As a result, the channel network (102) effectively reduces the drag coefficient by approximately 5% - 20% and increases the lift coefficient by 10%-20%. The improvement of the lift coefficient enhances the overall aerodynamic performance and allows for more efficient flight with reduced fuel consumption and improved manoeuvrability.

[0125] In another embodiment, the channel network (102) further optimizes the lift-to-drag ratio in a predefined range across different angles of attack. By strategically controlling airflow characteristics through the channels (102a), the airfoil (100) maintains smooth and attached flow over a wider range of operating conditions. The progressive flow optimization contours (104d) within the channels (102a) help generate localized low-pressure zones, reducing wake turbulence and drag while increasing lift production. Consequently, the channel network (102) enhances the lift-to-drag ratio by 5%-20% across different angles of attack and ensures superior aerodynamic efficiency in diverse flight regimes, including takeoff, cruise, and landing.

[0126] In yet another embodiment, the airfoil (100) is of material that enhances weight, strength, and durability. In an embodiment, the material of the airfoil (100) and channels (102a) is selected to meet structural requirements, environmental resilience requirements, and manufacturing feasibility.

[0127] In an embodiment, the airfoil (100) can be fabricated using advanced techniques such as CNC machining, precision molding, or 3D printing. These manufacturing processes enable accurate replication of the contoured channel geometry, ensuring that the aerodynamic benefits of the integrated channel network (CN) (102) are fully realized in practical applications. The use of lightweight composite materials further enhances the structural integrity of the airfoil (100) while minimizing weight, thereby maximizing fuel efficiency and load-carrying capacity.

[0128] In another embodiment, the airfoil (100) is defined by multiple pieces configured to be attached to each other. The multi-piece configuration facilitates the construction of larger airfoils and airfoils requiring segmental construction.

[0129] In yet another embodiment, the external surfaces, of entry contour sections (104a) and exit contour section (104c), are surface-finished to minimize aerodynamic resistance and ensure smooth airflow interaction.

[0130] In an embodiment, the airfoil (100) includes at least one span wise aerodynamic surface (SAS) which allows the flow of air laterally along the whole wing including on the upper surface (lOOd), the lower surfaces (100c), and the channels (102). The spanwise aerodynamic surface (SAS) facilitates collective aerodynamic effects across the entire span of the wing (106).

[0131] In another embodiment, the airfoil (100) is configured for scalability and adaptability, ensuring that the benefits of the channel network (102) and flow optimization contours (FOCs) (104d) can be applied across a wide range of aerodynamic platforms. The airfoil (100) can be effectively integrated in straight-wing airfoils, forward-swept, and backward-swept wing configurations, providing enhanced stability and drag reduction across various wing geometries. Additionally, the airfoil (100) is compatible with morphing wing technologies, allowing real-time shape adjustments to optimize aerodynamic performance during different flight phases. This adaptability makes the airfoil (100) particularly beneficial for unmanned aerial vehicles (UAVs), commercial aircraft, jets, and wind turbine blades, where aerodynamic efficiency directly impacts fuel consumption, operational range, and stability.

[0132] In still another embodiment, the airfoil (100) includes modular channel inserts configured to be inserted in pre-formed cavities within the airfoil's surface to adapt to different flight conditions.

[0133] In an embodiment, the airfoil (100) includes a combination of a passive channel approach (the passive flow control system) with a selective active flow control system, such as localized suction or blowing, which is activated only when needed to control flow separation.

[0134] In another embodiment, the airfoil (100) includes channels or ridges that change geometry in response to temperature changes associated with airflow speed, thereby adjusting the boundary layer control features in real-time or a channel of micro-flaps configured to be embedded into the airfoil surface. These micro-flaps act in a similar manner to the channels, to create vortices and manipulate flow to delay separation.

[0135] In still another embodiment, the airfoil (100) includes piezoelectric actuators to create subtle surface deformations on the airfoil (100), thereby mimicking the effect of the fixed channels by altering the boundary layer flow as required; or an internal network within the airfoil (100) that direct air from the leading edge (100a) and expel it through strategically placed outlets along the surface, thereby influencing the boundary layer and imitating the vortex generation of the channels.

[0136] In one embodiment of the airfoil (100) of the present disclosure, the channels (102a) are strategically integrated into the airfoil (100) to accommodate and coexist with existing and added internal wing structures such as spars, ribs, fuel tanks, and control systems, to ensure that the aerodynamic benefits are maintained without requiring modification of these internal structures.

[0137] Unlike active flow control systems that rely on external power sources, the airfoil (100) passively optimizes aerodynamic performance through airfoils ’s structural configuration. In an embodiment, the channels (102a) can also be integrated in the lower surface of the straight- winged airfoils. Figure 5 - 7 illustrates different views of a straight wing with channels at the lower surface.

[0138] In another embodiment, the airfoil (100) can be utilized in various applications where aerodynamic efficiency plays a critical role. In the aviation sector, the airfoil (100) finds applications in aircraft wings, ranging from narrow to wide-body aircraft. The airfoil (100) improves fuel efficiency and extends operational range. Additionally, the airfoil (100) can be employed in unmanned aerial vehicles (UAVs) and drones to offer a scalable solution to increase aerodynamic performance, prolong flight duration, and improve stability.

[0139] In another embodiment, beyond aviation, the airfoil (100) has applications in marine vessels. The channels (102a) can be implemented in hydrofoils or sailboat keels, where airfoil-like structures enhance lift generation and stability. In the renewable energy sector, the airfoil (100) improves the aerodynamic efficiency of wind turbine blades, and increases energy capture from wind resources.

[0140] Additionally, the airfoil (100) is applicable in the automotive industry, where aerodynamic properties contribute to enhanced vehicle performance. The airfoil reduces drag and optimizes airflow to achieve energy savings and enhance speed in high-performance vehicle body parts.

[0141] Advantageously, the airfoil (100), is configured to redefine flow control across a multitude of airfoil configurations and offer a unified, low-profile enhancement without the drawbacks of traditional, discrete vortex generators or the complexity of active flow control systems. The airfoil (100) manipulates the boundary layer autonomously through channels (102a) and eliminates the need for external power sources or mechanical actuation. Unlike conventional vortex generators and traditional airfoils (100’), which depend on additional energy inputs, the airfoil (100) regulates airflow through integrated channels and improves efficiency and reduces operational complexity.

[0142] The configuration of the channels (102a) increases the airfoil’s effective camber and optimizes the lift-to-drag ratio. Unlike conventional airfoils, which experience increased drag alongside lift enhancements, the airfoil (100) achieves a higher lift increase without a proportional rise in drag and generates superior aerodynamic efficiency.

[0143] EXPERIMENT The effectiveness of the airfoil (100), of the present disclosure was evaluated through Computational Fluid Dynamics (CFD) simulations, which aimed to compare the aerodynamic performance of the proposed airfoil (100) with that of a conventional airfoil (100’). The CFD study was conducted under uniform boundary conditions to ensure an objective and standardized performance assessment. It is important to note that while the present experimentation provides significant insight into the efficacy of the disclosed airfoil (100), this study does not limit the scope of the proposed idea. Various other sets of experiments can be conducted under real-world operational parameters, including wind tunnel testing, flight testing, and additional computational models, to further substantiate the aerodynamic benefits of the present disclosure.

[0144] In an exemplary embodiment, the CFD modeling process was carefully configured to ensure that the results were representative of realistic aerodynamic behavior. The first step in the study involved constructing 2D simulation domains for both the proposed airfoil (100) and the conventional airfoil (100’). These domains were configured with sufficient spatial clearance around the airfoil surfaces, ensuring that boundary interference was minimized, thereby allowing an accurate representation of airflow interaction. The dimensions of the simulation domain were selected based on realistic operational conditions, ensuring that the computational model closely resembled an actual airfoil in motion.

[0145] Once the simulation domain was established, a structured meshing technique was employed to discretize the flow domain. Special attention was given to refining the mesh in regions surrounding the airfoil walls, particularly near the channel network (CN) (102). This fine mesh resolution enabled a detailed capture of velocity gradients, pressure distributions, and turbulent vortices, which are critical for analyzing the aerodynamic impact of the embedded channels (102a). Figure 8 illustrates the discretized simulation domain, showcasing the refined mesh configuration employed for the airfoil (100).

[0146] After meshing, boundary conditions were applied to both airfoil models (100’ and 100) to ensure uniform comparison. A slip wall boundary condition was used for the upper and lower boundaries of the simulation domain, allowing the airflow to move freely without inducing artificial frictional effects. The inlet velocity was set to 50 m / s, ensuring that the airflow entering the simulation domain closely resembled standard operating conditions. The outlet boundary was maintained at 0 Pa pressure, allowing unrestricted airflow exit, simulating an open-flight environment. The domain fluid was set to air under standard atmospheric conditions, ensuring that the aerodynamic results were applicable to real- world flight scenarios. Additionally, a wall-layer model was enabled to accurately resolve boundary layer development, flow separation, and reattachment regions, which are critical parameters in assessing lift and drag characteristics.

[0147] A steady-state solver was selected for the CFD simulation, allowing the airfoil performance to be analyzed under constant flow conditions. This approach provided a direct and stable comparison between the conventional airfoil (100’) and the airfoil (100) of the present disclosure. Additionally, a turbulence model was implemented to capture turbulent flow structures around the airfoil surfaces. The selected turbulence model was particularly suited for predicting flow separation and reattachment points, ensuring a high-accuracy representation of aerodynamic effects introduced by the channel network (CN) (102).

[0148] Following the completion of the simulation, a detailed analysis of lift, drag, and lift-to-drag ratio (Cl / Cd) was conducted. The results confirmed that the airfoil (100) of the present disclosure outperformed the conventional airfoil (100’) in multiple aerodynamic aspects.

[0149] 1. Lift enhancement and pressure distribution:

[0150] The integration of the channel network (CN) (102) resulted in a significant increase in lift generation compared to the conventional airfoil (100’). The embedded channels (102a) function as passive aerodynamic enhancers, generating controlled vortex formations that augment the effective camber of the airfoil (100) without altering its external shape. These controlled vortex structures contribute to an increase in pressure differential between the upper surface (lOOd) and the lower surface (100c), leading to higher lift production. It is observed that the average lift increase of 10.64% compared to the conventional airfoil (100’), Low-pressure zones were generated along the lower surface (100c) due to vortex augmentation, effectively improving lift production. Figure 9 illustrates the lift force (Fl) variation across different angles of attack, showcasing the superior lift characteristics of the airfoil (100). The pressure plots in Figures 12 and 13 confirm the reduction of static pressure along the lower surface, demonstrating the pressure redistribution effects induced by the channel network (CN) (102).

[0151] 2. Drag reduction and flow stabilization: The proposed airfoil (100) exhibited a significant reduction in drag compared to the conventional airfoil (100’). The internal vortex flow within the channels (102a) facilitated a smoother airflow transition along the lower surface (100c), thereby reducing wake turbulence and minimizing pressure disparities. This optimized flow behavior contributed to a more efficient airflow path, reducing aerodynamic resistance. It is observed that average drag reduction of 7.12% across different angles of attack, the channel-induced airflow stabilization prevented early flow separation, ensuring that energy losses due to turbulence were minimized, and the airfoil (100) demonstrated more stable wake characteristics, resulting in a reduction of pressure drag. Figure 10 presents a comparative analysis of drag force (Fd) across different angles of attack, clearly indicating the drag-minimization effects of the proposed airfoil design.

[0152] 3. Lift-to-Drag ratio (Cl / Cd) improvement:

[0153] The airfoil (100) achieved an average improvement of 17.15% in Cl / Cd, demonstrating markedly superior aerodynamic efficiency compared to the conventional airfoil (100’). The ability of the channel network (CN) (102) to separate the conventional trade-off between increased camber and drag penalties highlights the innovative airflow optimization mechanism of the present disclosure. It is observed that the airfoil (100) successfully increased camber effects without the associated drag penalties, resulting in a more aerodynamically efficient design. Figure 11 illustrates the Cl / Cd ratio improvements observed across various angles of attack, confirming the superior aerodynamic balance of the disclosed airfoil.

[0154] Thus, the CFD-based experimental validation conclusively demonstrates that the airfoil (100) of the present disclosure provides superior aerodynamic performance compared to conventional airfoil configuration. The integration of the channel network (CN) (102) significantly improves lift production, reduces drag, and enhances the overall lift-to-drag ratio, making it an ideal candidate for various aerospace applications, including UAVs, commercial aircraft, and wind turbines.

[0155] Further, it is emphasized that this experiment does not limit the scope of the disclosed airfoil configuration. Additional experimental validations, including wind tunnel tests, flight tests, and transient simulations, can further refine and expand the understanding of the aerodynamic enhancements introduced by the present disclosure. The proposed internal airflow management strategy, as validated by the CFD simulations, provides a novel and scalable approach to aerodynamic optimization, ensuring enhanced performance without the complexity of active flow control mechanisms.

[0156] Figure 12 and Figure 13 illustrate pressure plots of the conventional airfoil and the airfoil of the present disclosure generated using the CFD algorithm. The graphical analysis clearly demonstrates the significant improvements in lift-to-drag ratio (Cl / Cd), lift (Fl), and drag (Fd) provided by the integrated channel network (ICN), validates the airfoil’s effectiveness in enhancing aerodynamic efficiency. Therefore, the introduction of the channel network (102a) into airfoil configuration marks a significant stride toward aerodynamic optimization and promises considerable advancements in efficiency and performance across diverse sectors.

[0157] The foregoing description of the embodiments has been provided for purposes of illustration and is not intended to limit the scope of the present disclosure. Individual components of a particular embodiment are generally not limited to that particular embodiment, but, are interchangeable. Such variations are not to be regarded as a departure from the present disclosure, and all such modifications are considered to be within the scope of the present disclosure.

[0158] TECHNICAL ADVANCEMENTS

[0159] The present disclosure described hereinabove has several technical advantages including, but not limited to, the realization of an airfoil with flow control channels, wherein:

[0160] • the integration of flow optimization contours (FOCs) within the channel network (CN) enables localized pressure modulation, which sustains boundary layer momentum, preventing premature flow separation and ensuring stable airflow attachment at varying angles of attack;

[0161] • the channel network (CN) modifies the pressure distribution along the lower surface, guiding airflow through structured pathways to smooth out turbulent regions, regulate boundary layer characteristics, minimize wake turbulence at the trailing edge, and effectively reduce pressure drag without introducing additional aerodynamic resistance; the airfoil maintains attached flow for extended regions, delaying flow separation and enabling structured airflow reattachment at the channel exit, which optimizes aerodynamic efficiency and allows for higher lift generation with reduced drag across different flight conditions; the seamless integration of the channel network (CN) within the lower surface of the airfoil eliminates external passive control elements such as vortex generators and winglets, thereby preventing additional surface friction, avoiding parasitic drag, and ensuring uninterrupted airflow distribution without protruding structures; unlike conventional active flow control mechanisms that rely on actuators, sensors, and energy-intensive systems, the proposed airfoil passively manipulates airflow through its predefined channel geometry, structurally guiding airflow without requiring mechanical intervention, thereby simplifying configuration and improving energy efficiency; the direct embedding of channels within the airfoil structure eliminates the need for additional mechanical components, moving parts, or external attachments, preserving structural integrity while maintaining weight efficiency, which contributes to overall aircraft performance optimization; the geometric configuration of the channels is optimized based on aircraft- specific parameters such as operating speed, altitude, and angle of attack, ensuring continuous airflow regulation and passive adaptation to varying aerodynamic conditions without requiring active control adjustments; the exit section of each channel is configured with a curvature profile that gradually directs airflow reattachment into the surrounding flow field, to ensure a smooth transition, reducing turbulence-induced pressure differentials, minimizing flow disruptions at the trailing edge, and lowering overall aerodynamic drag for improved efficiency; the channel network (CN) is scalable across different airfoil geometries and adaptable to various aircraft types, including UAVs, and commercial airliners, allowing customization based on aerodynamic performance requirements; and the proposed airfoil operates without reliance on moving components, actuators, or power-driven mechanisms, which eliminates wear-related failures, reduces mechanical maintenance requirements, decreases long-term operational costs, ensures durability over extended flight operations, and enhances overall reliability without the need for frequent servicing and maintenance.

[0162] The foregoing disclosure has been described with reference to the accompanying embodiments which do not limit the scope and ambit of the disclosure. The description provided is purely by way of example and illustration.

[0163] The embodiments herein and the various features and advantageous details thereof are explained with reference to the non-limiting embodiments in the following description. Descriptions of well-known components and processing techniques are omitted so as to not unnecessarily obscure the embodiments herein. The examples used herein are intended merely to facilitate an understanding of ways in which the embodiments herein may be practiced and to further enable those of skill in the art to practice the embodiments herein. Accordingly, the examples should not be construed as limiting the scope of the embodiments herein.

[0164] The foregoing description of the specific embodiments so fully reveal the general nature of the embodiments herein that others can, by applying current knowledge, readily modify and / or adapt for various applications such specific embodiments without departing from the generic concept, and, therefore, such adaptations and modifications should and are intended to be comprehended within the meaning and range of equivalents of the disclosed embodiments. It is to be understood that the phraseology or terminology employed herein is for the purpose of description and not of limitation. Therefore, while the embodiments herein have been described in terms of preferred embodiments, those skilled in the art will recognize that the embodiments herein can be practiced with modification within the spirit and scope of the embodiments as described herein.

[0165] Any discussion of devices, articles or the like that has been included in this specification is solely for the purpose of providing a context for the disclosure. It is not to be taken as an admission that any or all of these matters form a part of the prior art base or were common general knowledge in the field relevant to the disclosure as it existed anywhere before the priority date of this application.

[0166] While considerable emphasis has been placed herein on the components and component parts of the preferred embodiments, it will be appreciated that many embodiments can be made and that many changes can be made in the preferred embodiments without departing from the principles of the disclosure. These and other changes in the preferred embodiment as well as other embodiments of the disclosure will be apparent to those skilled in the art from the disclosure herein, whereby it is to be distinctly understood that the foregoing descriptive matter is to be interpreted merely as illustrative of the disclosure and not as a limitation.

Claims

CLAIMS:

1. An airfoil (100) with flow control channels, said airfoil (100) comprising: o a leading edge (100a) and a trailing edge (100b) defining a chord line (100c) therebetween; o an upper surface (lOOd), configured with a contoured convex profile and extending between said leading edge (100a) and said trailing edge (100b); o a lower surface (100c), configured with a contoured concave profile and extending between said leading edge (100a) and said trailing edge (100b); o a channel network (CN) (102) configured on an operative section of said lower surface (100c), said channel network (CN) (102) comprising a plurality of channels extending substantially along the longitudinal direction of said airfoil, wherein each of said channels (102a) is configured with flow optimization contours (FOCs) (104d), defining interior surfaces of said channels (102a), wherein said FOCs are configured to generate localized low-pressure zones along said lower surface (100c) and is further configured to stabilize the boundary layer by inducing laminar flow at the entry of said channel (102a), and directing airflow reattachment at the exit of said channels (102a) to reduce flow separation and enhance the lift-to-drag ratio across varying flight conditions.

2. The airfoil (100) as claimed in claim 1, wherein said progressive flow optimization contours (FOCs) (104d) of said channel (102a) are configured with: o an entry contour section (104a), configured near said leading edge (100a), said entry contour section (104a) configured to redirect incoming airflow in a controlled vortex pattern to generate localized regions of reduced pressure along said lower surface (100c) thereby increasing the differential pressure between said upper surface (lOOd) and lower surfaces (100c) to increase lift; o a central contour section (104b), configured adjacent to said entry contour section (104a) in proximity to said leading edge (100a), said central contour section (104b) is configured to modulate airflow velocity distribution within said channel (102a), thereby facilitating the controlled development of theboundary layer along the interior surfaces of said channels (102a) to delay flow separation; and o an exit contour section (104c), configured adjacent to said central contour section (104b) in proximity to said leading edge (100a), said exit contour section (104c) is configured with a curvature profile to enable airflow reattachment to the surrounding flow field, thereby minimizing wake vortices and reducing pressure drag to optimize the lift-to-drag ratio across varying flight conditions.

3. The airfoil (100) as claimed in claim 2, wherein said exit contour section (104c) of said flow optimization contours (FOCs) (104d) is configured with a reduced radius of curvature to facilitate direct airflow reattachment to the surrounding flow field, mitigate wake turbulence, thereby minimizing pressure drag.

4. The airfoil (100) as claimed in claim 3, wherein said channel network (CN) (102) are configured along a mid-chord region of said lower surface (100c), wherein said entry contour section (104a), said central contour section (104b) and said exit contour section (104c) of said progressive flow optimization contours (FOCs) (104d) collectively define a concave cross-sectional geometry, configured to alter the boundary layer characteristics along said lower surface (100c) to delay flow separation and maintain airflow attachment to the lower surface (100c).

5. The airfoil (100) as claimed in claim 4, wherein said flow optimization contours (FOCs) (104d) are defined by: o at least one depth dimension configured to alter airflow velocity; o at least one width dimension configured to vary pressure distribution; and o a spacing pattern between adjacent channels (102a), said pattern being configured based on the aerodynamic profile of said airfoil (100).

6. The airfoil (100) as claimed in claim 1, wherein said channel network (CN) (102) is configured with a pressure differential means (PDM), positioned operatively within said channel network (CN) (102), said pressure differential means (PDM) is configured to optimize pressure gradients during varying flight regimes to enhance the lift-to-drag ratio.

7. The airfoil (100) as claimed in claim 1, wherein said channel network (CN) (102) of said airfoil (100) is configured to reduce the drag coefficient and increase the lift coefficient to a predefined range.

8. The airfoil (100) as claimed in claim 1, wherein said channel network (CN) (102) of said airfoil (100) is configured to achieve a drag coefficient reduction in the range of 5%-20% and a lift coefficient enhancement in the range of 10%-20%.

9. The airfoil (100) as claimed in claim 1, wherein said channel network (CN) (102) of said airfoil (100) is configured to enhance the lift-to-drag ratio in a predefined range across different angles of attack.

10. The airfoil (100) as claimed in claim 1, wherein said channel network (CN) (102) of said airfoil (100) is configured to enhance the lift-to-drag ratio by 5%-20% across different angles of attack.

11. The airfoil (100) as claimed in claim 1, wherein the radius of curvature of said entry contour section (104a), said central contour section (104b) and said exit contour section (104c) of each channel (102a) is optimized within a predefined range to facilitate the generation of localized low-pressure zones along said lower surface (100c), regulate boundary layer characteristics at said entry contour section (104a), and direct airflow reattachment at said exit section (104c).

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