Deployable and retractable vortex dissipators and their applicable blades and engines

Abstract

This application provides a deployable vortex dissipator and its applicable blades and engines, relating to the field of aerospace technology. The deployable vortex dissipator is applicable to blades, including blade tips. The deployable vortex dissipator includes: a shape memory alloy sheet, the shape memory alloy sheet including a fixed portion and a movable portion connected together. The fixed portion is adapted to be fixed on the blade near the blade tip. The movable portion is configured to abut the fixed portion when the temperature of the shape memory alloy sheet is not greater than a first preset temperature, and to have a first angle with the fixed portion when the temperature of the shape memory alloy sheet is not less than a second preset temperature, wherein the first preset temperature is less than the second preset temperature; and multiple disturbance wires, the multiple disturbance wires being arranged in sequence, and one end of each disturbance wire being fixedly connected to a first end of the movable portion away from the fixed portion.

Description

Technical Field

[0001] This application relates primarily to the field of aerospace technology, and in particular to a deployable vortex dissipator and its applicable blades and engines. Background Technology

[0002] With increasingly stringent noise airworthiness standards, conventional fan noise reduction methods usually involve laying acoustic liner on the nacelle to reduce noise along the propagation path. However, for open rotor aero engines without an envelope casing, noise reduction along the propagation path is extremely difficult.

[0003] Therefore, there is an urgent need for a deployable vortex dissipator that can effectively reduce blade noise. Summary of the Invention

[0004] The technical problem to be solved by this application is to provide a deployable vortex dissipator and its applicable blades and engines, which can effectively reduce blade noise.

[0005] To address the aforementioned technical problems, this application provides a deployable vortex dissipator suitable for blades. The blade includes a blade tip and comprises: a shape memory alloy sheet, the shape memory alloy sheet including a fixed portion and a movable portion connected together. The fixed portion is adapted to be fixed on the blade near the blade tip. The movable portion is configured to abut the fixed portion when the temperature of the shape memory alloy sheet is not greater than a first preset temperature, and to have a first angle with the fixed portion when the temperature of the shape memory alloy sheet is not less than a second preset temperature, wherein the first preset temperature is less than the second preset temperature; and multiple perturbation wires, the multiple perturbation wires being arranged in sequence, and one end of each of the multiple perturbation wires being fixedly connected to a first end of the movable portion away from the fixed portion.

[0006] Optionally, the material of the shape memory alloy sheet includes a binary nickel-titanium alloy, in which nickel atoms account for 50.5% to 51%.

[0007] Optionally, the first preset temperature is 35℃~45℃, and / or the second preset temperature is 60℃~70℃.

[0008] Optionally, the first included angle is 45° to 60°.

[0009] Optionally, the length of the perturbation wire is 3mm to 5mm, and / or the diameter of the perturbation wire is 35μm to 45μm.

[0010] Optionally, the blades include open rotor blades.

[0011] To solve the above-mentioned technical problems, this application provides a blade suitable for an engine, comprising: a blade body including a blade tip, a blade root and a trailing edge located between the blade tip and the blade root, the trailing edge having a groove extending from the blade tip to the blade root in a first direction; and at least one of the above-mentioned expandable and retractable vortex dissipators, the at least one expandable and retractable vortex dissipator being disposed in the groove, and the fixing part of the at least one expandable and retractable vortex dissipator being fixedly connected to the blade body.

[0012] Optionally, the sum of the thickness of the movable part and the thickness of the fixed part of at least one expandable vortex dissipator is not greater than the depth of the groove.

[0013] Optionally, the ratio of the length of the groove in the first direction to the length of the trailing edge is 0.05 to 0.1.

[0014] Optionally, at least one deployable vortex dissipator is sequentially spaced in the groove along the first direction, and at least one deployable vortex dissipator has a gap with the inner sidewall of the adjacent groove in the second direction.

[0015] Optionally, the ratio of the width of the gap to the length of the groove in the second direction is 0.12 to 0.17.

[0016] Alternatively, the engine may include an open rotary engine.

[0017] To solve the above-mentioned technical problems, this application provides an engine, including: an engine body; and at least one blade as described above, wherein the at least one blade is fixedly connected to the engine body.

[0018] Compared with the prior art, this application has the following advantages: As the blade rotation speed increases, the blade temperature and blade noise also increase accordingly. Among them, the tip vortex corresponding to the blade tip is the main source of broadband noise. Based on this, by fixing the fixed part near the blade tip and making the movable part of the shape memory alloy sheet automatically form a first angle with the fixed part when the temperature of the shape memory alloy sheet is not lower than a second preset temperature, the disturbance wire fixedly connected to the movable part approaches the tip vortex and disperses the tip vortex, thereby reducing broadband noise during blade operation. Attached Figure Description

[0019] The accompanying drawings are included to provide a further understanding of this application; they are incorporated into and constitute a part of this application. The drawings illustrate embodiments of this application and, together with this specification, serve to explain the principles of this application. In the drawings:

[0020] Figure 1 This is a partial structural schematic diagram of a blade and a deployable vortex dissipator according to an embodiment of this application;

[0021] Figure 2 yes Figure 1A schematic diagram of the overall structure of the intermediate blade and the expandable / retractable vortex dissipator;

[0022] Figure 3 This is a schematic diagram of the tip vortex generated by a blade without a deployable vortex dissipator;

[0023] Figure 4 yes Figure 2 A schematic diagram of the tip vortex generated by the blades in the diagram;

[0024] Figure 5 yes Figure 2 A schematic diagram of the shape memory alloy sheet of the expandable vortex dissipator in a self-folding state;

[0025] Figure 6 yes Figure 2 A schematic diagram of the shape memory alloy sheet of the deployable vortex dissipator in the form of autonomous deployment; and

[0026] Figure 7 This is a partial structural schematic diagram of an engine according to an embodiment of this application. Detailed Implementation

[0027] To more clearly illustrate the technical solutions of the embodiments of this application, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are merely some examples or embodiments of this application. For those skilled in the art, these drawings can be applied to other similar scenarios without creative effort. Unless obvious from the context or otherwise specified, the same reference numerals in the drawings represent the same structures or operations.

[0028] As indicated in this application and claims, unless the context clearly indicates otherwise, the words "a," "an," "an," and / or "the" are not specifically singular and may include plural forms. Generally speaking, the terms "comprising" and "including" only indicate the inclusion of explicitly identified steps and elements, which do not constitute an exclusive list, and the method or apparatus may also include other steps or elements.

[0029] Unless otherwise specifically stated, the relative arrangement, numerical expressions, and values ​​of the components and steps described in these embodiments do not limit the scope of this application. It should also be understood that, for ease of description, the dimensions of the various parts shown in the drawings are not drawn to actual scale. Techniques, methods, and devices known to those skilled in the art may not be discussed in detail, but where appropriate, such techniques, methods, and devices should be considered part of the specification. In all examples shown and discussed herein, any specific values ​​should be interpreted as merely exemplary and not as limitations. Therefore, other examples of exemplary embodiments may have different values. It should be noted that similar reference numerals and letters in the following drawings denote similar items; therefore, once an item is defined in one drawing, it need not be further discussed in subsequent drawings.

[0030] In the description of this application, it should be understood that the orientation or positional relationship indicated by directional terms such as "front, back, up, down, left, right", "horizontal, vertical, horizontal" and "top, bottom" is usually based on the orientation or positional relationship shown in the accompanying drawings, and is only for the convenience of describing this application and simplifying the description. Unless otherwise stated, these directional terms do not indicate or imply that the device or element referred to must have a specific orientation or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation on the scope of protection of this application; the directional terms "inner" and "outer" refer to the inner and outer contours relative to the outline of each component itself.

[0031] For ease of description, spatial relative terms such as "above," "on top of," "on the upper surface of," "above," etc., are used herein to describe the spatial positional relationship of a device or feature as shown in the figures to other devices or features. It should be understood that spatial relative terms are intended to encompass different orientations in use or operation beyond the orientation of the device as described in the figures. For example, if the device in the figures were inverted, a device described as "above" or "on top of" other devices or structures would subsequently be positioned as "below" or "under" other devices or structures. Thus, the exemplary term "above" can include both "above" and "below." The device may also be positioned in other different ways (rotated 90 degrees or in other orientations), and the spatial relative descriptions used herein will be interpreted accordingly.

[0032] Furthermore, it should be noted that the use of terms such as "first" and "second" to define components is merely for the purpose of distinguishing the corresponding components. Unless otherwise stated, these terms have no special meaning and therefore should not be construed as limiting the scope of protection of this application. In addition, although the terminology used in this application is selected from commonly known and used terms, some terms mentioned in this application's specification may have been chosen by the applicant according to his or her judgment, and their detailed meanings are explained in the relevant sections of this description. Moreover, this application should be understood not only through the actual terms used, but also through the meaning implied by each term.

[0033] In the description of this specification, it should also be noted that, unless otherwise expressly specified or limited, the terms "installation," "connection," and "joining" should be interpreted broadly. For example, they can refer to a fixed connection, an integral connection, or a detachable connection; a mechanical connection or an electrical connection; a direct connection or an indirect connection through an intermediate medium, or a connection within two components, etc. Those skilled in the art can understand the specific meaning of the above terms in this specification according to the specific circumstances.

[0034] First, refer to Figure 3 In the field of aero-engines, during the rotation of the blade 20 driven by the aircraft engine, a corresponding tip vortex 30 is generated at the blade tip 211. The greater the rotational speed of the blade 20, the larger the tip vortex 30 becomes. This is understandable. Figure 3 Each black dot represents a tip vortex 30. It's important to note that the tip vortex 30 is closely related to the broadband noise generated by the engine. Specifically, the larger the tip vortex 30, the stronger the corresponding broadband noise. In other words, the engine produces greater broadband noise at high speeds compared to low speeds.

[0035] In this regard, we will continue to refer to Figure 1 and Figure 2 One embodiment of this application proposes a deployable vortex dissipator 10, which is suitable for blades 20 and can reduce broadband noise caused by the tip vortex 30 of the blade 20. The blade 20 includes a tip 211. Continuing to refer to... Figure 1 and Figure 2The deployable vortex dissipator 10 includes a shape memory alloy sheet 11 and multiple perturbation wires 12. The shape memory alloy sheet 11 includes a fixed portion 111 and a movable portion 112 connected together. In this embodiment, the fixed portion 111 is adapted to be fixed on the blade 20 near the blade tip 211. In this embodiment, the movable portion 112 is configured to abut against the fixed portion 111 when the temperature of the shape memory alloy sheet 11 is not greater than a first preset temperature, and to form a first angle with the fixed portion 111 when the temperature of the shape memory alloy sheet 11 is not less than a second preset temperature, wherein the first preset temperature is less than the second preset temperature. Furthermore, in this embodiment, the multiple perturbation wires 12 are arranged sequentially, and one end of each of the multiple perturbation wires 12 is fixedly connected to a first end 1121 of the movable portion 112 away from the fixed portion 111.

[0036] Understandably, in this embodiment, the shape memory alloy sheet 11, due to the shape memory effect, folds autonomously when the movable part 112 of the shape memory alloy sheet 11 is against the fixed part 111 at low temperatures (i.e., temperatures not exceeding a first preset temperature), and autonomously unfolds when the movable part 112 and the fixed part 111 are at a first angle at high temperatures (i.e., temperatures not less than a second preset temperature). Based on this, since the disturbance wire 12 is fixedly connected to the first end 1121 of the movable part 112, when the shape memory alloy sheet 11 unfolds autonomously, multiple disturbance wires 12 move away from the fixed part 111, causing the trailing edge of the blade 20 near the blade tip 211 to no longer be a nearly straight structure, but rather an irregular structure. This disperses the leakage flow (i.e., the disturbance flow field) passing through the blade tip 211, thereby reducing the blade tip vortex 30 and achieving the effect of reducing broadband noise. (Exemplary example) Figure 4 yes Figure 3 A schematic diagram showing the reduction in tip vortex 30 of the blade 20 after being subjected to disturbance wire 12.

[0037] It should be noted that while the disturbance wire 12 can reduce broadband noise, its disturbance to the flow field may also reduce engine efficiency. Therefore, in this embodiment, the movable part 112 is further positioned against the fixed part 111 when the shape memory alloy sheet 11 is folded, so that the disturbance wire 12 is also close to the fixed part 111, thereby reducing or eliminating the disturbance effect of the disturbance wire 12 on the flow field and thus not affecting engine efficiency.

[0038] Understandably, aircraft, such as airplanes, may be in different states during flight, such as stable cruise flight and unstable edge flight. Compared to cruise flight, the blades 20 often have a higher rotational speed in edge flight, resulting in greater noise. Furthermore, airworthiness regulations impose strict limits on the noise generated by the aircraft. In response, the deployable vortex dissipator 10 of this embodiment can automatically drive the disturbance wire 12 to disturb the flow field and reduce noise in edge flight by increasing the temperature of the blades 20, and automatically drive the disturbance wire 12 to not disturb the flow field in cruise flight by decreasing the temperature of the blades 20, thereby improving engine efficiency and achieving better engine cruise efficiency. Moreover, by fully utilizing the temperature changes of the blades 20 in cruise and edge flight conditions, no additional control device is needed to control the state of the disturbance wire 12, enabling convenient and effective noise reduction.

[0039] In some embodiments, the first preset temperature is 35°C to 45°C. Further, the first preset temperature is preferably 40°C, which is slightly higher than the normal temperature of the blade 20 under cruise conditions, thereby effectively preventing the disturbance wire 12 from interfering with the flow field and thus improving engine cruise efficiency. In some embodiments, the second preset temperature is 60°C to 70°C. Further, the second preset temperature is preferably 65°C, which is slightly lower than the normal temperature of the blade 20 under edge conditions, thereby driving the disturbance wire 12 to interfere with the flow field and thus reducing noise.

[0040] Continue to refer to Figure 1 and Figure 2In some embodiments, the shape memory alloy sheet 11 is made of a binary nickel-titanium alloy. It should be noted that the shape change of the binary nickel-titanium alloy at a specific temperature mainly depends on the proportion of nickel and titanium atoms in the binary nickel-titanium alloy. For example, for a first preset temperature of 40°C and a second preset temperature of 65°C, the proportion of nickel atoms in the binary nickel-titanium alloy is 50.5% to 51%, thereby enabling the shape memory alloy sheet 11 to autonomously fold and unfold within the corresponding first and second preset temperature ranges. Furthermore, in some embodiments, the first included angle is 45° to 60°. In some embodiments, the length of the perturbation wire is 3mm to 5mm, more preferably 4mm. In some embodiments, the diameter of the perturbation wire is 35μm to 45μm, more preferably 40μm. In some embodiments, the blade 20 includes an open rotor blade. It is understood that, since open rotor engines do not have an envelope casing compared to conventional aero engines, it is impossible to suppress noise along the noise propagation path by setting noise reduction devices on the envelope casing. Therefore, the deployable vortex dissipator 10 of this application, being directly mounted on the open rotor blade, has a wider application prospect in open rotor engines. It should be noted that this application does not limit the type of blade 20; in some embodiments, the blade 20 is a fully enclosed blade. Furthermore, this application does not limit the arrangement of the disturbance wires 12; in some embodiments, the disturbance wires 12 are arranged sequentially in the same direction, and in some embodiments, the disturbance wires 12 are evenly distributed in a designated area.

[0041] Continue to refer to Figure 1 and Figure 2 Another aspect of this application proposes a blade 20. For example... Figure 1 and Figure 2 As shown, in one embodiment of this application, the blade 20 is adapted for an engine, and the blade 20 includes a blade body 21 and a plurality of expandable and retractable vortex dissipators 10 according to any of the above embodiments. The blade body 21 includes a blade tip 211, a blade root 212, and a trailing edge 213 located between the blade tip 211 and the blade root 212. In this embodiment, the trailing edge 213 has a groove 214 extending from the blade tip 211 to the blade root 212 along a first direction, i.e., the x-direction. It is understood that in this embodiment, the trailing edge 213 is located near the side of the blade tip 211 where the tip vortex 30 is generated. In this embodiment, the expandable and retractable vortex dissipators 10 are disposed in the groove 214, and the fixing portion 111 of each expandable and retractable vortex dissipator 10 is fixedly connected to the blade body 21, thereby making each expandable and retractable vortex dissipator 10 located near the side of the blade tip 211 where the tip vortex 30 is generated, thereby reducing the broadband noise generated by the blade 20 under edge operating conditions through the expandable and retractable vortex dissipators 10. It should be noted that this application does not limit the number of deployable and retractable vortex dissipators 10 in the blade 20. In some embodiments, the blade 20 contains only one deployable and retractable vortex dissipator 10.

[0042] Continue to refer to Figure 1 and Figure 2 In some embodiments, the sum of the thickness of the movable portion 112 and the thickness of the fixed portion 111 of at least one deployable vortex dissipator 10 is not greater than the depth of the groove 214. Further refer to... Figure 5 In cruise conditions, when the movable part 112 is abutted against the fixed part 111, the shape memory alloy sheet 11 and the disturbance wire 12, i.e., the entire deployable vortex dissipator 10, are completely located within the groove 214, resulting in a smooth trailing edge 213. This further reduces the impact of the deployable vortex dissipator 10 on the flow field around the blade 20 during cruise, thereby further improving engine efficiency. Correspondingly, in these embodiments, the length of the disturbance wire 12, the length of the movable part 112, and the first included angle are mutually configured so that at least a portion of the disturbance wire 12 extends beyond the groove 214 when the shape memory alloy sheet 11 deploys autonomously, achieving [the desired effect]. Figure 3 Interference from the tip vortex 30. Figure 6 This is a schematic diagram showing the disturbance wire 12 extending out of the groove 214 when the shape memory alloy sheet 11 unfolds autonomously.

[0043] Continue to refer to Figure 2 In some embodiments, the ratio of the length of the groove 214 in the first direction to the length of the trailing edge is 0.05 to 0.1. In one example, the length of the trailing edge is 1 m, and the length of the groove 214 in the first direction is 0.08 m. In these embodiments, this ratio setting prevents the groove 214 from being too long, causing the deployable vortex dissipators 10 arranged in the groove 214 to be too far away from the blade tip 211, thereby ensuring that each deployable vortex dissipator 10 in the groove 214 can effectively dissipate vortex energy. Figure 3 The tip vortex 30 produces a suppressive effect.

[0044] Continue to refer to Figure 1 In some embodiments, at least one deployable vortex dissipator 10 is sequentially spaced in the groove 214 along a first direction, and at least one deployable vortex dissipator 10 has a gap with the inner wall of the adjacent groove 214 in the second direction, i.e., the y-direction. This avoids the deployable vortex dissipator 10 and the blade 20 from being compressed against each other due to thermal expansion caused by temperature changes under different operating conditions, which could lead to damage to the deployable vortex dissipator 10 and the blade 20, or prevent the shape memory alloy sheet 11 from deploying smoothly and autonomously, thus failing to achieve the effect of reducing noise. Furthermore, in some embodiments, the ratio of the width of the gap to the length of the groove 214 in the second direction is 0.12 to 0.17, i.e. Figure 1The ratio of the width of the intermediate gaps d1 and d2 to the length of the groove 214 in the second direction is 0.12 to 0.17. By setting this ratio, these embodiments ensure that the expandable vortex dissipator 10 and the blade 20 do not come into contact with each other after thermal expansion, while also avoiding the limitation of the size of the expandable vortex dissipator 10, which could lead to insufficient noise reduction. In some embodiments, the engine includes an open rotor engine.

[0045] This application also proposes an engine. (See reference...) Figure 7 In one embodiment of this application, the engine 100 includes an engine body 40 and at least one blade 20 as described in any of the above embodiments, and the blade 20 has a deployable vortex dissipator 10. At least one blade 20 is fixedly connected to the engine body 40. It is understood that the engine body 40 is adapted to drive the blade 20 to rotate. It should be noted that... Figure 7 To highlight the expandable vortex dissipator 10, its size has been enlarged. Figure 7 The relative dimensional relationship between the deployable vortex dissipator 10 and the blades 20 or the engine body 40 is not limited.

[0046] The basic concepts have been described above. Obviously, for those skilled in the art, the above disclosure is merely illustrative and does not constitute a limitation of this application. Although not explicitly stated herein, those skilled in the art may make various modifications, improvements, and corrections to this application. Such modifications, improvements, and corrections are suggested in this application, and therefore remain within the spirit and scope of the exemplary embodiments of this application.

[0047] Furthermore, this application uses specific terms to describe embodiments of the application. For example, "an embodiment," "one embodiment," and / or "some embodiments" refer to a particular feature, structure, or characteristic related to at least one embodiment of the application. Therefore, it should be emphasized and noted that "an embodiment," "one embodiment," or "an alternative embodiment" mentioned twice or more in different locations in this specification do not necessarily refer to the same embodiment. In addition, certain features, structures, or characteristics in one or more embodiments of the application can be appropriately combined.

[0048] Similarly, it should be noted that, in order to simplify the description of the present application and thus aid in the understanding of one or more embodiments, the foregoing description of the embodiments of the present application sometimes combines multiple features into a single embodiment, drawing, or description thereof. However, this disclosure method does not imply that the subject matter of the present application requires more features than those mentioned in the claims. In fact, the embodiments contain fewer features than all the features of the single embodiments disclosed above.

[0049] In some embodiments, numbers describing the quantity of components and attributes are used. It should be understood that such numbers used in the description of embodiments are modified in some examples with the terms "approximately," "approximately," or "generally." Unless otherwise stated, "approximately," "approximately," or "generally" indicates that the numbers are allowed to vary by ±20%. Accordingly, in some embodiments, the numerical parameters used in the specification and claims are approximate values, which may be changed depending on the characteristics required by individual embodiments. In some embodiments, numerical parameters should take into account specified significant digits and employ a general method of digit reservation. Although the numerical ranges and parameters used to confirm their breadth of scope in some embodiments of this application are approximate values, in specific embodiments, such values ​​are set as precisely as feasible.

[0050] Although this application has been described with reference to specific embodiments, those skilled in the art should recognize that the above embodiments are only used to illustrate this application, and various equivalent changes or substitutions can be made without departing from the spirit of this application. Therefore, any changes or modifications to the above embodiments within the essential spirit of this application will fall within the scope of the claims of this application.

Claims

1. A deployable vortex dissipator, characterized in that, Suitable for blades, the blades including a leaf tip, comprising: A shape memory alloy sheet, comprising a fixed portion and a movable portion connected together, the fixed portion being adapted to be fixed on the blade near the blade tip, the movable portion being configured to abut the fixed portion when the temperature of the shape memory alloy sheet is not greater than a first preset temperature, and to form a first angle with the fixed portion when the temperature of the shape memory alloy sheet is not less than a second preset temperature, wherein the first preset temperature is less than the second preset temperature; and Multiple disturbance wires are arranged in sequence, and one end of each disturbance wire is fixedly connected to the first end of the movable part away from the fixed part.

2. The deployable vortex dissipator as described in claim 1, characterized in that, The material of the shape memory alloy sheet includes a binary nickel-titanium alloy, in which the proportion of nickel atoms is 50.5% to 51%.

3. The deployable vortex dissipator as described in claim 1, characterized in that, The first preset temperature is 35℃~45℃, and / or the second preset temperature is 60℃~70℃.

4. The deployable vortex dissipator as described in claim 1, characterized in that, The first included angle is 45°~60°.

5. The deployable vortex dissipator as described in claim 1, characterized in that, The length of the disturbance wire is 3mm to 5mm, and / or the diameter of the disturbance wire is 35μm to 45μm.

6. The deployable vortex dissipator as described in claim 1, characterized in that, The blades include open rotor blades.

7. A blade, characterized in that, Applicable to engines, including: The leaf body includes a leaf tip, a leaf root, and a trailing edge located between the leaf tip and the leaf root, the trailing edge having a groove extending from the leaf tip towards the leaf root in a first direction; and At least one deployable vortex dissipator as described in any one of claims 1 to 6, wherein at least one of the deployable vortex dissipators is disposed in the groove, and the fixing portion of at least one of the deployable vortex dissipators is fixedly connected to the blade body.

8. The blade as described in claim 7, characterized in that, The sum of the thickness of the movable part and the thickness of the fixed part of at least one of the expandable and retractable vortex dissipators is not greater than the depth of the groove.

9. The blade as described in claim 7, characterized in that, The ratio of the length of the groove in the first direction to the length of the trailing edge is 0.05 to 0.

1.

10. The blade as claimed in claim 7, characterized in that, At least one of the expandable vortex dissipators is sequentially spaced in the groove along a first direction, and at least one of the expandable vortex dissipators has a gap with the inner sidewall of the adjacent groove in a second direction.

11. The blade as claimed in claim 10, characterized in that, The ratio of the width of the gap to the length of the groove in the second direction is 0.12 to 0.

17.

12. The blade as claimed in claim 7, characterized in that, The engine includes an open rotary engine.

13. An engine, characterized in that, include: Engine body; as well as At least one blade as described in any one of claims 7 to 12, wherein at least one of the blades is fixedly connected to the engine body.

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