RU2721428C1 - Flexible sail - Google Patents

Abstract

FIELD: power engineering.

SUBSTANCE: invention relates to wind power engineering and can be used in wind power plants for conversion of wind energy to electric/mechanical, as well as in sailing shipbuilding for creation of sailing vessels and is aimed at improvement of aerodynamic efficiency of flexible wing-sail equipped with wishbone boom in wide range of wind speeds. Flexible wing-sail comprises two bent branches of boom-bark connected with front and rear yokes, connected with possibility of rotation around longitudinal axis. parallel to the boom symmetry axis. In middle part of wishbone boom branches, having optimum profile of flexible wing-sail for rated weak wind, holes are made, at least, with bushings fixed in them. In the bushings edges of holes on the outer side are rounded, through which an adjustment cable passes, forming a closed loop, ends of which are brought to the external surface of the branches of the wishbone boom and fixed on the tension drums located on the wishbone boom near mast (1).

EFFECT: higher aerodynamic efficiency of flexible wing-sail.

3 cl, 6 dwg

Description

The invention relates to the field of wind energy and can be used to convert wind energy into electrical or mechanical energy in wind energy and sailing shipbuilding.

A device is known for increasing the aerodynamic efficiency of a flexible wing, in particular a Bermuda grotto, which is a boom variable in the horizontal plane of curvature, containing a beam with a mounting device to the mast and a guide for mounting the lower sail pin, the beam is made in the form of several links with limiters for the angle of mutual rotation and connected to each other pivotally with the possibility of rotation in the horizontal plane (AS USSR 1512858, publ. 07.10.1989).

The disadvantages of the analogue are the large mass, complexity and high cost of the design. To ensure the required rigidity of the structure, which, in addition to the bending moment, is affected by torque, high precision manufacturing and an increase in the transverse dimensions of the nodes that make up the structure are required.

There is a known design called geek-wishbone, consisting of two branches convex relative to the geek-wishbone axis, used on sailing boards or on yachts of the Freedom type (Electronic resource: http://www.barque.ru/horizon/1984/rig_yachts_such_as_freedom, Sailing yachts type "Freedom").

Among the designs of geek-Wishbone, a structure is known that contains two curved branches connected to the front and rear forks, which are rotatably connected around a longitudinal axis parallel to the axis of symmetry of the boom and are fixed from several positions (USSR AS No. 1342820, publ. 07.10.1987 g .).

According to the number of similar features and the achieved result, this technical solution is selected as a prototype of the claimed technical solution.

The disadvantages of the prototype are that this design provides the convenience of controlling the sailing board, but does not affect the aerodynamic efficiency of the sail, which is determined mainly by the profile of the sail and the influence of the mast on the nature of the air flow around the sail. The deformation properties of the canvas, sail cutting, mast flexibility, angle of attack of the air flow, etc. influence the formation of the profile of the flexible wing. Under the influence of these factors, the profile of the sail of this design is far from optimal. In addition, with each tack change, manipulations are needed to change the position of the branches of geek-Wishbon. As well as a low coefficient of aerodynamic quality.

The technical result, the achievement of which the present invention is directed, consists in increasing the aerodynamic efficiency of a flexible wing-sail equipped with a boom-windshield in a wide range of wind speeds.

To achieve the specified technical result in a flexible sail-wing, which contains two curved branches of the boom-geek wing, connected with the front and rear forks, rotatably connected around the longitudinal axis parallel to the axis of symmetry of the boom, in the middle of the branches of the geek-wire with the optimal profile of the flexible wing-sails for the calculated weak wind, holes, at least one, were made with bushings fixed in them, at which the edges of the holes are rounded from the outside and through which an adjustment cable passes through which forms a closed loop, the ends of which are brought out to the outer surface of the branches of geek-Wishbone and fixed on the tension reels located on the boom-bishbone near the mast.

In addition, the claimed technical solution has optional features characterizing its particular cases, namely:

- the front fork is made in the form of a horseshoe-shaped shackle with external and internal coaxial cylindrical surfaces, the axis of which is located at the intersection of the diametrical plane of the hull and the plane tangent to the mast mast. The inner surface of the horseshoe-shaped shackles is connected to a shoe made of a material with a low coefficient of friction and mounted on the mast from the bow of the vessel. The outer surface of the horseshoe-shaped shackles is connected to the bushings mounted on the mast symmetrically with respect to the diametrical plane. The horseshoe-shaped shackle is equipped with consoles oriented towards the mast, which are fastened to the branches of the geek-Wishbon;

- the cross section of the branches of geek-Wishbon is made in the form of a segment facing outwardly convex.

Distinctive features of the proposed design from the above known, closest to it, are the holes, at least one, in the middle of the branches of geek-wishbone, having an optimal profile of a flexible wing-sail for the estimated weak wind; fastening in the holes of the bushings from a material with a low coefficient of friction; threading through the bushings of the adjusting cable forming a closed loop; the conclusion of the ends of the loop on the outer surface of the branches of geek-Wishbon fixing the ends of the loop on the tension drums located on the geek-Wishbone at the mast.

Due to the presence of these signs, the wing-sail is pressed against the leeward branch of the geek-wishbone, has an optimal aerodynamic shape. An adjusting cable threaded through the holes in the wing-sail and branches of the boom-wing, when winding its ends on the tension reels, allows to reduce the distance between the branches of the boom-wing, which increases the aerodynamic efficiency of the flexible wing-sail with increasing wind speed. The proposed design of the geek-wishbone casing allows you to set

the design of the boom on fixed mast, and when it is installed on the rotary mast of a drop-shaped cross-section, continuous flow of the mast from the leeward side is achieved and, as a result, the aerodynamic efficiency of the mast-sail system is increased.

The invention is illustrated by the drawings shown in FIG. 1-6.

In FIG. 1 shows a side view of the proposed flexible wing-sail.

In FIG. 2 is a horizontal section of a geek-wishbone with a plane passing through the axis of the holes.

In FIG. 3 is a cross section of a geek-Wishbone with a vertical plane passing through the axis of the holes.

In FIG. 4 is a horizontal section through the forging of a boom geek mounted on a fixed mast.

In FIG. 5 is a top view of a geek Wishbone mounted on a swivel mast.

In FIG. 6 is a top view of a geek-wishbone mounted on a fixed mast at various positions relative to the diametrical plane with maximum and minimum branch curvature.

The proposed design comprises a mast 1, branches of a boom-hitchbone 2, an adjusting cable 3, holes with bushings fixed in them 4, tension drums not shown, a flexible wing-sail 5, a horseshoe-shaped shackle 6 of a boom-hitchbone, shoe 7, rollers 8, lykpaz 9. The arrows indicate the tension of the adjusting cable 3 on the drum.

The proposed design works as follows.

The front crib of the flexible wing-sail 5 is inserted into the lift base 9 of the mast 1 and lift it. Then, the adjustment cable 3 is threaded into the holes for the bushings 4 and the flexible wing-sail 5, and its ends are fixed on the tension drums. Next, tension the adjusting cable 3, so that the curvature of the branches 2 of the boom-whishbon corresponds to the expected wind speed, then the clew angle of the flexible wing-sail 5 is tensioned.

According to (Ch. Markhai. The theory of sailing. - Moscow, Publishing House "Physical Culture and Sports", 1970, S. 100-120) the magnitude of the weight of the sail varies from 1/7 for light wind to 1/30 from chords to strong winds. Therefore, branches 2 of geek-Wishbon of the proposed design should have, when manufacturing, an arrow of deflection of more than 1/7 of the chord.

The design of geek-Wishbone works mainly for longitudinal compression, so the presence of two cross-links, which are the adjusting cable 3, can reduce the weight of the device by about an order of magnitude and use the most favorable cross-sectional shape of the branches of 2 Geek-Wishbone for this design, for example, segmented.

The inventive flexible wing-sail involves the use of sailing fabric with minimal stretch. The presence of holes in the flexible wing-sail 5 does not have any effect on its operation, since it is adjacent to the inner surface of the branch 2 of geek-Wishbon.

When the wind speed changes, the belly of the flexible wing-sail 5 can be quickly changed by changing the curvature of the branches 2 by tensioning or loosening the adjustment cable 3.

Equipping the geek-Wishbone with a horseshoe-shaped forging 6 of the proposed design allows it to be installed on the mast 1 in operation by fixing the shoe 7, rollers 8 and an additional section of the lift base 9 on its surface.

To increase the rigidity of the horseshoe-shaped shackles 6, a channel shape can be given in cross section to it.

A flexible wing-sail can be used in wind farms representing a closed rail track with carts mounted on it equipped with generators and sails.

To increase the efficiency of such wing-sails, it is possible to equip them with sails 5 with geek-wishbone of the proposed design. Why it is necessary to equip them with tensioning drums with an electric drive controlled by a wind speed sensor.

Claims (3)

1. A flexible wing-sail, containing two curved branches (2) of geek-Wishbone connected with the front and rear forks, connected with the possibility of rotation around a longitudinal axis parallel to the axis of symmetry of the boom, characterized in that in the middle part of the branches (2) boom -wishbon, having an optimal profile of a flexible wing-sail (5) for the calculated weak wind, holes, at least one, were made with fixed bushings (4), in which the edges of the holes are rounded from the outside and through which an adjustment cable (3) ), forming a closed loop, the ends of which are brought to the outer surface of the branches (2) of the geek-Wishbone and are mounted on the tension drums located on the Geek-Wishbone at the mast (1). 2. A flexible wing-sail according to claim 1, characterized in that the front fork is made in the form of a horseshoe-shaped shackle (6) with external and internal coaxial cylindrical surfaces, the axis of which is located at the intersection of the diametrical plane of the hull and the plane tangent to the liquid base (9) the mast (1), the inner surface of the horseshoe-shaped shackle (6) is adjoined to the shoe (7) made of material with a low coefficient of friction and mounted on the mast (1) from the bow of the vessel, and the outer surface of the horseshoe-shaped shackle (6) is attached to the rollers, mounted on the mast (1) symmetrically with respect to the diametrical plane, the horseshoe-shaped shackle (6) is equipped with consoles oriented towards the mast (1), which are fastened to the branches (2) of the geek-washbone. 3. Flexible wing-sail according to claim 1, characterized in that the cross-section of the branches (2) of the boom-fly is made in the form of a segment facing the bulge outward.

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