A method for designing marine energy utilization blades and the designed impeller

Abstract

This invention discloses a design method for marine energy utilization blades and the designed impeller. Based on a spherical profile lift-drag combined design concept, the marine energy utilization blade consists of a helical blade and two booster blades, one at the top and one at the bottom. The helical blade is determined by the initial airfoil line along the scanning path of the helical blade. The two booster blades are respectively connected to the upper and lower ends of the helical blade, and are determined by a bucket-shaped profile along the spherical arc guide line. The impeller consists of three sets of blades, a central shaft, and two end plates, all connected spherically. The three sets of blades are evenly distributed on the spherical profile. The central shaft is connected to the upper and lower end plates, providing support for rotation. The upper and lower end plates provide support and fixation, and are connected to the power generation device. This invention's impeller can achieve efficient and stable operation in omnidirectional low-velocity flow environments such as deep seas, and has advantages such as omnidirectional response to unpredictable ocean currents, high self-starting capability and operational stability, and optimized structural parameters for efficient operation.

Description

Technical Field

[0001] This invention belongs to the field of deep-sea low-speed water flow energy engineering technology, and particularly relates to a design method for marine energy utilization blades and the designed impeller. Background Technology

[0002] With the increasing pursuit of renewable energy, ocean current energy, as a clean and renewable energy form, is gradually gaining global attention. For ocean currents with high velocity, stable flow direction, and relatively concentrated energy, axial-flow turbines have become the main equipment for efficient power generation. However, in deep-sea areas with low velocity, unstable flow direction, and dispersed energy, traditional power generation equipment often struggles to operate stably and is inefficient. Therefore, developing a device that is highly adaptable, stable, and capable of generating electricity efficiently even at low flow velocities has become an important research direction in the field of ocean current energy utilization. The Darrieus impeller, a classic wind power generation device, has been attempted for underwater power generation in recent years. Its vertical axis design allows the impeller to effectively utilize the energy from flows in all directions; however, due to structural reasons, the impeller experiences significant torque fluctuations within a single rotation cycle, which adversely affects its startup and continuous stable operation. Summary of the Invention

[0003] The purpose of this invention is to provide a design method for marine energy utilization blades and a rotor designed accordingly. The designed blades can omnidirectionally respond to unpredictable ocean currents while possessing high self-starting capability, strong operational stability, and high energy conversion efficiency. This rotor employs a unique spherical structure design, achieving efficient utilization of omnidirectional ocean currents through a combination of helical blades, booster blades, a central shaft, and upper and lower end plates. The helical blade design enables the rotor to maintain stable torque output under different current angles, while the booster blades enhance the rotor's stability and self-starting capability. Furthermore, the rotor's central shaft and upper and lower end plates provide robust support for the entire structure, enabling stable operation in harsh environments such as the deep sea.

[0004] The first aspect of this invention proposes a design method for marine energy utilization blades, which are used to design marine energy utilization blades. The designed blades can achieve omnidirectional response to unpredictable ocean currents while having high self-starting capability, strong operational stability, and high energy conversion efficiency.

[0005] The design method includes the following steps:

[0006] The spherical profile is determined by a given radius, wherein the marine energy utilization blade has a spherical profile.

[0007] Determine the central axis of rotation, which is located at the center of the spherical profile and is a slender cylinder, determined by a given length and radius;

[0008] The upper end plate is defined as being located at the top of the central rotating shaft and the top of the spherical contour, and is a flat cylinder. The lower end face of the upper end plate is concentrically connected to the upper end face of the central rotating shaft, and is determined by a given length and radius.

[0009] The lower end plate is defined as follows: the lower end plate consists of two parts, both of which are flat cylinders. The upper part is located at the lower end of the central rotating shaft and the bottom of the spherical contour, and the lower part is located outside the bottom of the spherical contour. The upper surface of the lower end plate is concentrically connected to the lower end surface of the central rotating shaft, and is determined by a given length and radius.

[0010] The helical blades are defined as follows: the helical blades are evenly distributed in three equal parts on the spherical profile of the rotor, and are determined by the initial airfoil line along the scanning path line of the helical blades.

[0011] The booster blade is determined by lofting along the guide line of the booster blade on the spherical contour. One end of the booster blade is connected to the port of the helical blade, and the other end is connected to the upper end plate or the lower end plate.

[0012] Due to design limitations, traditional underwater impellers experience significant torque fluctuations throughout their complete rotation cycle. This torque instability not only affects the impeller's startup process but also hinders its long-term stable operation. The blades designed using the marine energy utilization blade method of the first aspect of this invention maintain stable torque output under different incoming flow angles, while the presence of booster blades enhances the overall stability and self-starting capability of the device. Furthermore, the flexible design process allows sufficient room for blade optimization, enabling significant improvement in energy conversion efficiency through reasonable parameter configuration.

[0013] In some embodiments, the radius of the spherical profile is determined by the design requirements of the wheel:

[0014]

[0015] Where R is the radius of the spherical profile, P is the design power, η is the efficiency of the impeller, ρ is the fluid density, and V is the fluid velocity.

[0016] In some embodiments, the relationship between the given length and radius of the central rotating shaft is determined by the following formula:

[0017]

[0018] Among them, L z R is the length of the central rotating shaft. zLet R be the radius of the central axis of rotation, and λ be the radius of the spherical profile. l and λ r These are the length ratio and radius ratio of the central rotating shaft, respectively.

[0019] In some embodiments, the relationship between the given length and radius of the upper end plate is determined by the following formula:

[0020]

[0021] Among them, L u R is the length of the upper end plate. u Let R be the radius of the upper end plate, and let u be the radius of the spherical profile. l and u r These represent the length ratio and radius ratio of the upper end plate, respectively.

[0022] In some embodiments, the given length and radius of the upper half of the lower end plate are equal to the given length and radius of the upper end plate, and the relationship between the given length and radius of the lower half of the lower end plate is determined as follows:

[0023]

[0024] Among them, L d R is the length of the lower half of the lower end plate. d Let R be the radius of the lower half of the lower end plate, and d be the radius of the spherical profile. l and d r These are the length ratio and radius ratio of the lower half of the lower end plate, respectively.

[0025] In some embodiments, the helical blade is determined by an initial airfoil line along the helical blade scanning path line, wherein the initial airfoil line is:

[0026]

[0027] Where P is the spherical coordinate of the center point of the initial airfoil, and φ c The horizontal angle is θ. c The vertical angle is defined by the initial airfoil line located on the XOY parallel plane passing through point P, where x is the abscissa of the initial airfoil line and y is the ordinate of the initial airfoil line. u Let y be the ordinate of the upper half of the starting airfoil. d The vertical coordinate of the lower half of the starting airfoil line is given. The equation of the starting airfoil line can be NACA airfoil, Gottingen airfoil, RAF-6 airfoil, etc.

[0028] The scanning path of the helical blade is as follows:

[0029]

[0030] Where R is the radius of the spherical profile, (N x ,0,N z The out-of-plane normal coordinates of the spiral blade scanning path line are used to determine the spiral blade.

[0031] In some embodiments, the booster blade is determined by lofting the projection curve of the booster blade planar water bucket profile onto the cylindrical surface of the upper end plate and the projection curve of the booster blade planar water bucket profile onto the helical blade along the projection curve of the booster blade planar guide line onto the spherical profile. The equation of the projection curve of the booster blade planar water bucket profile onto the cylindrical surface of the upper end plate is:

[0032]

[0033] Among them, Y u and Y d These are the upper and lower curves of the booster blade's planar bucket-shaped profile, located in the plane cos(φ). c )x+sin(φ c )y=0.

[0034] The projection curve of the booster blade planar guide line onto the spherical profile is:

[0035]

[0036] Where Y2 is the guide line of the booster blade plane, located in the plane cos(θ) c )x+sin(θ c z = 0.

[0037] A second aspect of the invention also proposes a rotating wheel.

[0038] According to an embodiment of the present invention, the runner includes marine energy utilization blades, which are designed using the marine energy utilization blade design method described in any embodiment of the first aspect of the present invention.

[0039] The runner of the second aspect of the present invention adopts the marine energy utilization blade designed by the marine energy utilization blade design method of any one of the first aspects of the present invention. Therefore, it can achieve efficient and stable operation in omnidirectional low-velocity flow environments such as deep sea. It has the advantages of omnidirectional response to unpredictable ocean currents, high self-starting capability and operational stability, and efficient operation with optimized structural parameters.

[0040] The above description is merely an overview of the technical solution of the present invention. In order to better understand the technical means of the present invention and to implement it in accordance with the contents of the specification, the preferred embodiments of the present invention are described in detail below with reference to the accompanying drawings. Attached Figure Description

[0041] Figure 1 This is a three-dimensional structural diagram of a rotating wheel according to an embodiment of the present invention;

[0042] Figure 2 This is a schematic diagram of the spiral blade structure according to an embodiment of the present invention;

[0043] Figure 3 This is a schematic diagram of the booster blade structure according to an embodiment of the present invention.

[0044] Figure label:

[0045] 1000-Ocean Energy Utilization Runner (hereinafter referred to as the runner);

[0046] 1-Spherical profile; 2-Central pivot; 3-Upper end plate; 4-Upper half of lower end plate; 5-Lower half of lower end plate; 6-Helical blade; 7-Booster blade;

[0047] I - Rotation axis centerline; II - Initial airfoil line; III - Process airfoil line; IV - Helical blade scanning path line; V - Booster blade planar water bucket-shaped profile line; VI - Booster blade planar water bucket-shaped profile line; VII - Booster blade planar guide line;

[0048] A - Initial airfoil; B - Termination airfoil; C - Scanning path plane; D - Center axis vertical plane; E - Booster blade guide plane. Detailed Implementation

[0049] The specific embodiments of the present invention will be described in further detail below with reference to the accompanying drawings and examples. The following examples are for illustrative purposes only and are not intended to limit the scope of the invention.

[0050] The following is combined Figures 1 to 3 This invention describes a method for designing marine energy utilization blades and the resulting runner.

[0051] This invention provides a design method for marine energy utilization blades and a designed impeller. The marine energy utilization blade, designed based on a spherical profile and a lift-drag combination design concept, consists of a helical blade and two booster blades, one at the top and one at the bottom. The helical blade is determined by the initial airfoil line along the scanning path of the helical blade. The two booster blades are respectively connected to the upper and lower ends of the helical blade and are determined by a bucket-shaped profile laid out along the spherical arc guide line. The impeller based on this marine energy utilization blade consists of three sets of marine energy utilization blades, a central rotating shaft, and two end plates, all connected spherically. The three sets of marine energy utilization blades are evenly distributed on the spherical profile. The central rotating shaft is connected to the upper and lower end plates, providing support for rotation. The upper and lower end plates provide support and fixation and can be further connected to a power generation device. Details are as follows:

[0052] The first aspect of this invention proposes a design method for marine energy utilization blades, based on a lift-drag combined approach using a spherical profile. The blade has an overall spherical profile, employing a lift-type blade as the main working component, while simultaneously using an impact-type connecting rod blade to assist the lift blade, thereby improving self-starting performance and operational stability. During the design process, by sequentially determining the spherical profile, central shaft, upper end plate, lower end plate, helical blade, and booster blade, a complete marine energy utilization blade can be formed.

[0053] like Figures 1 to 3 As shown, according to the first aspect of the present invention, a marine energy utilization blade design method is used to design a marine energy utilization blade, comprising a helical blade 6 and an upper and lower booster blade 7; the helical blade 6 is defined by the initial airfoil line II along the helical blade scanning path line IV; the upper and lower booster blades are respectively connected to the upper and lower ends of the helical blade 6, and the other end is connected to the upper end plate 3 and the lower end plates 4 and 5, respectively. The booster blades are defined by the projection curve of the booster blade planar water bucket profile line V onto the cylindrical surface of the upper end plate 3 and the booster blade planar water bucket profile line VI onto the helical blade. The projection curve on blade 6 is determined by lofting along the projection curve of the booster blade plane guide line VII on the spherical contour 1; the three helical blades 6, the three upper and three lower booster blades 7, the central rotating shaft 2, and the upper end plate 3 and the lower end plates 4 and 5 are connected as a whole to the spherical contour 1; the three helical blades 6 are evenly distributed in three equal parts on the spherical contour 1; the central rotating shaft 2 is connected to the upper end plate 3 and the lower end plate 4, and plays a supporting role in rotation, which is determined by the extrusion of the circular surface; the upper end plate 3 and the lower end plates 4 and 5 play a supporting and fixing role, and can be further connected to the power generation device, which is determined by the extrusion of the circular surface.

[0054] like Figures 1 to 3 As shown, the marine energy utilization blade design method of the first aspect of the present invention includes the following steps:

[0055] Determine the spherical profile 1, wherein the marine energy utilization blade has a spherical profile 1, determined by a given radius;

[0056] Determine the central axis of rotation 2, which is located at the center of the spherical profile and is a slender cylinder, determined by a given length and radius;

[0057] The upper end plate 3 is defined as being located at the top of the central rotating shaft 2 and the top of the spherical contour 1, and is a flat cylinder. The lower end face of the upper end plate 3 is concentrically connected to the upper end face of the central rotating shaft 2, and is determined by a given length and radius.

[0058] The lower end plates 4 and 5 are defined. The lower end plates 4 and 5 are composed of two parts, both of which are flat cylinders. The upper part 4 is located at the lower end of the central rotating shaft 2 and the bottom of the spherical contour 1, and the lower part 5 is located outside the bottom of the spherical contour 1. The upper end face of the lower end plate 5 is concentrically connected with the lower end face of the central rotating shaft 2, and is determined by a given length and radius.

[0059] The helical blade 6 is determined, and the helical blade 6 is evenly distributed in three equal parts on the spherical profile 1, and is determined by the initial airfoil line II along the helical blade scanning path line IV;

[0060] The booster blade 7 is determined by lofting along the projection curve of the booster blade plane water bucket profile line V on the cylindrical surface of the upper end plate 3 and the projection curve of the booster blade plane water bucket profile line VI on the spiral blade 6.

[0061] Due to design limitations, traditional underwater impellers experience significant torque fluctuations throughout their complete rotation cycle. This torque instability not only affects the impeller's startup process but also hinders its long-term stable operation. The blades designed using the marine energy utilization blade method of the first aspect of this invention maintain stable torque output under different incoming flow angles, while the presence of booster blades enhances the overall stability and self-starting capability of the device. Furthermore, the flexible design process allows sufficient room for blade optimization, enabling significant improvement in energy conversion efficiency through reasonable parameter configuration.

[0062] In some embodiments, the radius of the spherical profile 1 is determined by the design requirements of the wheel:

[0063]

[0064] Where R is the radius of the spherical profile 1, P is the design power, η is the efficiency of the impeller, ρ is the fluid density, and V is the fluid velocity.

[0065] In some embodiments, the relationship between the given length and radius of the central rotating shaft 2 is determined as follows:

[0066]

[0067] Among them, L z R is the length of the central rotating shaft 2. z R is the radius of the central axis of rotation 2, R is the radius of the spherical profile 1, and λ is the radius of the spherical profile 1. l and λ r These are the length ratio and radius ratio of the central rotating shaft 2, respectively.

[0068] In some embodiments, the relationship between the given length and radius of the upper end plate 3 is determined as follows:

[0069]

[0070] Among them, L u R is the length of the upper end plate 3. u R is the radius of the upper end plate 3, R is the radius of the spherical profile 1, and u l and u r These are the length ratio and radius ratio of the upper end plate 3, respectively.

[0071] In some embodiments, the given length and radius of the upper half 4 of the lower end plate are equal to the given length and radius of the upper end plate 3, and the relationship between the given length and radius of the lower half 5 of the lower end plate is determined as follows:

[0072]

[0073] Among them, L d R is the length of the lower half of the lower end plate 5. d R is the radius of the lower half of the lower end plate 5, R is the radius of the spherical profile 1, and d l and d r These are the length ratio and radius ratio of the lower half of the lower end plate 5, respectively.

[0074] In some embodiments, the helical blade 6 is determined by the initial airfoil line II along the helical blade scanning path line IV, wherein the initial airfoil line II is:

[0075]

[0076] Where P is the spherical coordinate of the center point of the initial airfoil line II, and φ c The horizontal angle is θ. c The vertical angle is given, and the initial airfoil line II is located on the XOY parallel plane passing through point P, where x is the abscissa of the initial airfoil line II, and y is the ordinate. u Let y be the ordinate of the upper half of the initial airfoil line II. d The ordinate is the lower half of the initial airfoil line II. The equation of the initial airfoil line II can be for NACA airfoil, Gottingen airfoil, RAF-6 airfoil, etc.

[0077] The scanning path line IV of the helical blade is:

[0078]

[0079] Where R is the radius of the spherical profile 1, (N x,0,N z To determine the out-of-plane normal coordinates of the helical blade scanning path line IV of the helical blade 6.

[0080] In some embodiments, the booster blade 7 is determined by lofting the projection curve of booster blade planar water bucket profile V onto the cylindrical surface of the upper end plate 3 and the projection curve of booster blade planar water bucket profile VI onto the helical blade 6 along the projection curve of booster blade planar guide line VII onto the spherical contour 1. The equation of the projection curve of booster blade planar water bucket profile V onto the cylindrical surface of the upper end plate 3 is:

[0081]

[0082] Among them, Y u and Y d These are the upper and lower halves of curve V on the planar bucket-shaped profile of the booster blades, located in the plane cos(φ). c )x+sin(φ c )y=0.

[0083] The projection curve of the booster blade planar guide line VII onto the spherical profile 1 is:

[0084]

[0085] Where Y2 is the booster blade planar guide line VII, located in the plane cos(θ) c )x+sin(θ c z = 0.

[0086] A second aspect of the invention also proposes a rotating wheel.

[0087] According to a second aspect of the present invention, the runner includes marine energy utilization blades, which are designed using a marine energy utilization blade design method according to any one of the first aspects of the present invention.

[0088] The runner of the second aspect of the present invention adopts the marine energy utilization blade designed by the marine energy utilization blade design method of any one of the first aspects of the present invention. Therefore, it can achieve efficient and stable operation in omnidirectional low-velocity flow environments such as deep sea. It has the advantages of omnidirectional response to unpredictable ocean currents, high self-starting capability and operational stability, and efficient operation with optimized structural parameters.

[0089] The above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention. It should be noted that for those skilled in the art, several improvements and modifications can be made without departing from the technical principles of the present invention, and these improvements and modifications should also be considered within the scope of protection of the present invention.

Claims

1. A method for designing marine energy utilization blades, characterized in that, The design method for designing blades for marine energy utilization includes the following steps: The spherical profile is determined by a given radius, wherein the marine energy utilization blade has a spherical profile. Determine the central axis of rotation, which is located at the center of the spherical profile and is a slender cylinder, determined by a given length and radius; The upper end plate is defined as being located at the top of the central rotating shaft and the top of the spherical contour, and is a flat cylinder. The lower end face of the upper end plate is concentrically connected to the upper end face of the central rotating shaft, and is determined by a given length and radius. The lower end plate is defined as follows: the lower end plate consists of two parts, both of which are flat cylinders. The upper part is located at the lower end of the central rotating shaft and the bottom of the spherical contour, and the lower part is located outside the bottom of the spherical contour. The upper surface of the lower end plate is concentrically connected to the lower end surface of the central rotating shaft, and is determined by a given length and radius. The helical blades are defined as follows: the helical blades are evenly distributed in three equal parts on the spherical profile of the rotor, and are determined by the initial airfoil line along the scanning path of the helical blades. The booster blade is determined by lofting along the projection curve of the booster blade planar water bucket profile on the cylindrical surface of the upper end plate and the projection curve of the booster blade planar water bucket profile on the helical blade along the projection curve of the booster blade planar guide line on the spherical contour. The helical blade is determined by the initial airfoil line along the scanning path of the helical blade. The initial airfoil line is: （5） Where P is the spherical coordinate of the center point of the initial airfoil line. The horizontal angle is θ. c The vertical angle is defined by the initial airfoil line located on the XOY parallel plane passing through point P, where x is the abscissa of the initial airfoil line and y is the ordinate of the initial airfoil line. u Let y be the ordinate of the upper half of the starting airfoil. d The vertical coordinate of the lower half of the initial airfoil line is given. The initial airfoil line equation is for the NACA airfoil, Gottingen airfoil, or RAF-6 airfoil. The scanning path of the helical blade is as follows: （6） Where R is the radius of the spherical profile, (N x , 0 , N z The out-of-plane normal coordinates of the spiral blade scanning path line are used to determine the spiral blade. The booster blade is determined by lofting the projection curve of the booster blade planar water bucket profile onto the cylindrical surface of the upper end plate and the projection curve of the booster blade planar water bucket profile onto the helical blade along the projection curve of the booster blade planar guide line onto the spherical contour. The equation of the projection curve of the booster blade planar water bucket profile onto the cylindrical surface of the upper end plate is: （7） Among them, Y u and Y d These are the upper and lower curves of the booster blade's planar bucket-shaped profile, located in the plane. superior; The projection curve of the booster blade planar guide line onto the spherical profile is: （8） Where Y2 is the guide line of the booster blade plane, located in the plane cos(θ) c )x+sin(θ c z=0.

2. The marine energy utilization blade design method according to claim 1, characterized in that, The radius of the spherical profile is determined by the design requirements of the wheel: （1） Where R is the radius of the spherical profile, P is the design power, η is the efficiency of the impeller, ρ is the fluid density, and V is the fluid velocity.

3. The marine energy utilization blade design method according to claim 2, characterized in that, The relationship between the given length and radius of the central rotating shaft is determined by the following formula: （2） Among them, L z R is the length of the central rotating shaft. z Let R be the radius of the central axis of rotation, and λ be the radius of the spherical profile. l and λ r These are the length ratio and radius ratio of the central rotating shaft, respectively.

4. The marine energy utilization blade design method according to claim 3, characterized in that, The relationship between the given length and radius of the upper end plate is determined by the following formula: （3） Among them, L u R is the length of the upper end plate. u Let R be the radius of the upper end plate, and let u be the radius of the spherical profile. l and u r These represent the length ratio and radius ratio of the upper end plate, respectively.

5. The marine energy utilization blade design method according to claim 4, characterized in that, The given length and radius of the upper half of the lower end plate are equal to the given length and radius of the upper end plate. The relationship between the given length and radius of the lower half of the lower end plate is determined as follows: （4） Among them, L d R is the length of the lower half of the lower end plate. d Let R be the radius of the lower half of the lower end plate, and d be the radius of the spherical profile. l and d r These are the length ratio and radius ratio of the lower half of the lower end plate, respectively.

6. A rotary wheel, characterized in that, Includes the marine energy utilization blade as described in any one of claims 1 to 5.

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