WO2019074405A1 - Wind power assembly (variants) - Google Patents

Abstract

The invention relates to wind power and concerns wind power assemblies having a horizontally positioned wind wheel rotor axis and in which the wind wheel blades are made in the form of Magnus cylinders that rotate about their own axes. The technical effect provided by the two variants of the invention, which are related by a single inventive concept, is that the rotating Magnus cylinders compress the wind current in a direction toward the wind wheel axis, thus decreasing induced drag for the rotating cylinders, and also increasing the wind energy usage coefficient by compressing the wind current toward the wind wheel axis and increasing the effective area of the captured wind current.

Description

 WIND POWER INSTALLATION (OPTIONS)

The invention relates to wind power engineering and relates to wind power plants (WPP) with a horizontal axis of the wind wheel rotor, in which the blades of the wind wheel are made in the form of cylinders rotating around its axis. The lifting force acting on the cylinders in the transverse flow arises due to the Magnus effect [3], which is characterized by the appearance of the lifting force (Magnus force) when the cylinder rotates in the transverse flow. This force is used to rotate the propeller rotor, similar to the lifting force of the traditional blade, but it has a much larger value.

 An important problem of wind power is the use of relatively low wind speeds, less than 6-8 m / s, characteristic of continental regions. In particular, in Russia such regions constitute up to 80% of the entire territory. Traditional wind turbines of blade type under such conditions are not very effective due to the low lift force of the blade and, accordingly, the low torque of the wind wheel [1].

It is known to use wind turbines with rotating cylinders (rotors) instead of blades [2]. The action of such wind turbines is based on the Magnus effect, which is expressed in the occurrence of a transverse force acting on the body, rotating in the incident flow of gas or liquid. In accordance with the Zhukovsky theorem, for a cylinder of infinite length rotating in a transverse air flow, the Magnus force acting on an element of its length dl is equal to

Here: p - air density; V is the velocity vector of the oncoming air flow; G is the vector of circulation created by the rotation of the cylinder; ω is the vector of angular velocity of rotation of the cylinder around its axis; R is the cylinder radius; a - coefficient taking into account the detachable flow past a cylinder (for real si- system in most cases a <0.5); dm is the mass of air displaced by the cylinder element.

In [1, 4], the results of experimental studies of a separately rotating cylinder, as well as a wind wheel assembly with rotating cylinders in a wind tunnel, are presented. It is shown that the main parameters determining the wind wheel efficiency are: the speed of rotation of the cylinders, reduced to the velocity of the incident flow 6> = oR /; cylinder elongation equal to the ratio of its length to diameter A = L / 2R; diameter of the end washer, preventing the flow from the end of the cylinders, referred to the diameter of the cylinder C = d _m 12R. It was found that the optimal values of the main parameters are: 6> “4, L> \ 2, C <2. In such an optimal mode, the Magnus force is an order of magnitude and more superior to the driving force of the blade. This increases the propeller torque and provides a sufficiently effective wind turbine at low wind speeds, starting at approximately 2 m / s. It is known that with decreasing wind speed V, wind turbine power decreases proportionally to V ³ . However, such a decrease can be somewhat compensated by an increase in the diameter of the wind wheel, since the power of the wind turbine grows in proportion to the square of the diameter.

The resistance of the rotating cylinder to the incident flow is several tens of times higher than the resistance of the blade of similar dimensions. In this case, the main contribution is made precisely by the inductive resistance, proportional to the ratio of the square of the lifting force of the rotating cylinder divided by its elongation F ² 1 I [4]. With increasing (from zero) speed of rotation of the wind wheel, in the plane of the wind wheel there is a nonzero projection of the force of resistance of the cylinder, which creates a moment of forces braking the wheel. Thus, for effective operation of wind turbines on the Magnus effect, it is necessary to take measures to reduce the inductive resistance of the cylinders. A significant decrease in inductive resistance can be achieved by increasing A, as well as by optimizing the shape of the cylinders. A famous wind energy generator according to the US patent Ν ° 7504740, which operates using the Magnus effect, contains a wind wheel with a horizontal rotating shaft for transmitting a moment of force from the wind wheel to an electric generator. The wind wheel contains radially mounted Magnus rotors in the form of cylinders, which are rotated around their axis using electric motors. Washers are installed on the outer ends of the cylinders to prevent the swirling flow from the ends of the cylinders and thereby reducing their inductive resistance. The surface of the cylinders has spiral ribs-screws with winding in the direction of rotation of the cylinders, which ensure the movement of air from the ends of the cylinders to the axis of the wind wheel to increase Magnus lifting force. The disadvantages of this technical solution include significant energy costs for rotating the cylinder end washers and complicating the design of the cylinders due to the presence of rib-screws.

 Famous wind turbine according to the patent of the Russian Federation содержащ ° 2381380, containing a wind-wheel with a horizontal axis of rotation and radially mounted Magnus rotors in the form of cylinders, each of which is made with non-rotating root and rotating end parts with a washer at the end, as well as a cylinder drive and electric generator. The rotating part of the rotors is made of a cylindrical part with a truncated cone at the end, the base of which is facing the cylinder and has a diameter greater than the diameter of the cylinder, while the cylindrical and conical surfaces have spiral ribs-screws wound in the direction of rotation cylinders, starting from their root section to the washer, which ensure the movement of air from the ends of the cylinders to the axis of the wind forest.

 This technical solution, as the closest to the stated technical essence and the achieved result, was taken as a prototype.

This design solution reduces the inductive resistance of the cylinders and improves their flow around, bringing it closer to the non-separable one, which allows reducing the speed of rotation of the cylinders and reducing the corresponding the corresponding costs of power while maintaining the number of revolutions and power of the wind wheel. The disadvantages of this technical solution is the high inductive resistance of the rotating cylinders of the wind wheel, as well as the low utilization of wind energy (IEV). The disadvantages of this technical solution include significant energy costs for rotating end washers and cones, as well as complicating the design of cylinders due to the presence of augers and cones.

 The objective of the invention is to reduce the inductive resistance of the rotating cylinders of the wind wheel, as well as to increase the utilization of wind energy (KIEV).

 The essence of the first independent object of the invention as a technical solution is expressed in the following set of essential features, sufficient to solve the above problem of the invention.

 According to the first independent object of the invention, a wind power installation comprising a wind wheel with a horizontal axis of rotation and radially mounted Magnus rotors in the form of cylinders rotating around their longitudinal axes from an internal drive, and an electric generator, is characterized by the fact that their longitudinal axes lie in the plane normal to the horizontal axis of the wind wheel, but do not intersect with this axis.

 In addition, the first independent object of the invention is characterized by the presence of a number of additional optional features, namely:

 - cylinders can be equipped with fixedly fixed ends at their outer ends.

 The essence of the second independent object of the invention as a technical solution is expressed in the following set of essential features, sufficient to solve the above problem of the invention.

According to the second independent object of the invention, a wind power installation comprising a wind wheel with a horizontal axis of rotation and radially mounted Magnus rotors in the form of cylinders rotating the circle of its longitudinal axes from the built-in drive, and the electric generator, is characterized by the fact that the cylinders are installed so that the longitudinal axes of the cylinders intersect with the horizontal axis of the wind wheel, while the longitudinal axes of the cylinders are placed at an angle to the plane normal to the horizontal axis of the wind wheel.

 In addition, the second independent object of the invention is characterized by the presence of a number of additional optional features, namely:

 - cylinders can be equipped with fixedly fixed ends at their outer ends.

 Provided by both variants of the invention, having a common invention, the technical result is that the rotating Magnus cylinders compress the wind flow towards the axis of the wind wheel, which leads to a decrease in the inductance of the rotating cylinders, and also to increase by compressing the wind flow to the wind wheel axis and increasing the effective area of the wind flow to be captured.

 The essence of the proposed technical solution is illustrated by the drawing, in which in FIG. 1 shows the first version of the claimed technical solution, figure 2 - the second option.

The first version of the declared wind turbine contains a wind wheel 1 with a horizontal axis of rotation, which can be rotated on a fixed support 2 in the direction of the wind. On the wind wheel 1 there are at least two Magnus 3 cylinders rotating around their longitudinal axes from the built-in drives (conventionally not shown). Cylinders 3 are provided with fixedly fixed ends 4 at their outer ends. The longitudinal axes of the cylinders 3 lie in a plane normal to the horizontal axis of the propeller 1, but do not intersect with this axis. When the direction of the wind speed vector V is perpendicular to the plane normal to the horizontal axis of the wind wheel 1, the vector of angular velocity of rotation of each cylinder 3 ω is directed to the central region of the wind wheel 1. Then, taking into account (1), the Magnus force F _m will be perpendicular to the longitudinal axes cylinders 3, causing the propeller 1 to rotate counterclockwise. But the occurrence of the Magnus force inevitably leads to the appearance of a force equal in magnitude and opposite in direction to the force F _N , With which each rotating cylinder 3 acts on the wind flow. Due to the chosen cylinder orientation, force F has a non-zero component FR directed to the horizontal axis of the windwheel 1. Thus, in this design, each rotating cylinder 3 compresses the wind flow towards the horizontal axis of the windwheel 1, which leads to a decrease in inductive resistance of the rotating cylinders 3, as well as to an increase in KIEV due to the compression of the wind flow to the axis of the wind wheel 1 and an increase in the effective area of the wind flow to be captured.

The second version of the declared wind turbine contains a wind wheel 1 with a horizontal axis of rotation, which can be rotated on a fixed support 2 in the direction of the wind. There are at least two Magnus 3 cylinders mounted on the wind wheel, rotating around their longitudinal axes from the built-in drives (conventionally not shown). Cylinders 3 are equipped with fixedly fixed ends 4 on their outer ends. The longitudinal axes of cylinders 3 intersect with the horizontal axis of the wind wheel 1, but do not lie in a plane normal to the axis of the wind wheel 1, but make angle A. With the wind. , the vector of angular velocity of rotation of each cylinder 3 ω is directed to the center of the wind wheel 1. In the reference system associated with the wind wheel 1, the element of the length of each cylinder 3 is affected by two components of the Magnus force. The first of these, Fm, is due to the vector product of the wind velocity V and the vector ω. The second component of the Magnus force F _2m is due to the product of the vector ω by the velocity V _{2 of the} motion of an element of cylinder 3 length in a plane normal to the horizontal axis of the wind wheel 1. The component of speed V ₂ increases with the frequency of rotation of the wind wheel 1 and also as the cylinder element 3 moves away from the center of the wind wheel1. The Magnus force component F _{2m is} perpendicular to cylinder 3 and makes angle A with the wind speed vector V. But the appearance of F _2m inevitably leads to the appearance equal to it in magnitude and opposite in direction ly F _N , With which each rotating cylinder 3 acts on the wind flow. Due to the chosen orientation of the cylinders 3, the force F _N has a non-zero component in the plane perpendicular to the horizontal axis of the wind wheel1. Thus, in this design, each rotating cylinder 3 compresses the wind flow towards the wind wheel axis 1, which should lead to a decrease in the inductive resistance of the rotating cylinders, as well as to an increase in CIEF due to the compression of the wind stream to the wind wheel axis 1 and identification of the effective area of the captured wind flow.

 Additional reduction of the inductive resistance of the rotating cylinders 3 can be achieved in both versions of the declared wind turbine by installing the tips 4 on the outer ends of the cylinders 3, which are fixed in the reference system associated with the wind wheel, and additional energy is not expended on their rotation.

 The claimed device in both versions can be implemented using known equipment, technical and technological means.

 Literature:

 [1] Bychkov N.M. “Wind turbine with Magnus effect. 1. Results of model studies "Thermophysics and aeromechanics. - 2004. -T. 1 1, Ν ° 4.- p. 583-596

 [2] Ochunov M. The Magnus effect is in the air and under water (according to the materials of the foreign press) // Inventor and Innovator. - 1985. Ν ° 6. - p.22-23.

 [3] Loitsyansky L., G. Mechanics of fluid and gas. - M .: Drofa, 2003.

 [4] Bychkov N.M. “Wind turbine with Magnus effect. 2. Characteristics of a rotating cylinder »Thermophysics and aeromechanics. - 2005. - V. 12, N ° 1.— C.

159-175.

Claims

CLAIM 1. Wind power plant, including a wind wheel with a horizontal axis of rotation and radially mounted Magnus rotors in the form of cylinders rotating around their longitudinal axes from the built-in drive, and an electric generator, characterized in that the cylinders are installed so that their longitudinal axes lie in planes normal to the horizontal axis of the windmill, but do not intersect with this axis.  2. Installation according to claim 1, characterized in that the cylinders are provided with fixed tips at their outer ends.  3 Wind turbine installation, including a wind wheel with a horizontal axis of rotation and radially mounted Magnus rotors in the form of cylinders rotating around their longitudinal axes from the built-in drive, and an electric generator, characterized in that the cylinders are installed so that the longitudinal axes of the cylinders intersect with the horizontal the axis of the wind wheel, with the longitudinal axes of the cylinders placed at an angle to the plane normal to the horizontal axis of the wind wheel.  4. Installation according to Clause 3, characterized in that the cylinders are provided with fixed ends at their outer ends.