DE2144573A1 - RIGID SAIL - Google Patents

Description

Rigid sail Attempts have already been made several times to convert the Aircraft construction known profiles, especially for watercraft as high-quality sails to use.

Many solutions for salvaging the sail were given, few, however, for controlling the angle of attack of the sail. It became conventional by bulkheads or by land wheels via gearboxes. Has been to a constant adjustment of the angle of attack of the sail, depending on the apparent Wind thought, so wind vanes were put forward, their effect in view however, there is a lack of optimal adjustment of the sail. Your disguise is cumbersome and not fast enough.

Since the position of the wind vane in relation to the sail is practically every change of the angle of incidence of the wind would have to be corrected, for fast maneuvers therefore this If the sail does not guide properly, good rigid sails result in slight angular deviations excessive disruptive forces that can lead to capsizing.

In contrast to conventional sails, which have an incorrect setting by changes in shape on the sail, e.g. fluttering or bulging, and the Adjustment after the direction of the apparent wind is indicated by the stander is possible, an adjustment based on external characteristics is not possible with the rigid sail. Sailing according to Stander is hardly possible because of the pronounced tip vortex of a rigid sail falsifies the display of the stand.

The rigid sail unit has an aerodynamically favorable profile opposite the conventional sail significantly higher ratio of the thrust change per change in angle of attack (dC5 / ddt.

Due to this property, a rigid sail reacts much more strongly to changes in the direction of the apparent wind with changes in size and direction of power than is the case with a conventional sail.

In the case of screeching winds with large changes in wind force, it therefore changes the force on the sail is very strong when its angle of attack changes the apparent Winds is not constantly being adjusted.

Adjustment by hand is difficult; because of the lack of one clearly visible display on the sail itself, this would have to be done by measuring the angle of attack and their display. A corresponding automatic would of course be conceivable, which controls the feathering position independently. However, it complicates what is in itself simple Sails and requires a source of energy that is normally not found on a sailboat is available.

The automatic adjustment of the angle of attack of the sail can take over an auxiliary wing, which acts like a horizontal stabilizer of an airplane.

Fig. 1 This auxiliary wing 2, which acts as a tail unit, is in the plane of the rigid sail 1 behind this on a support arm 3 as a tail boom so that it can be rotated attached that the axis of rotation 4 of the tail unit 1 approximately parallel to the main axis of the sail 5 is.

The tail unit 2 can be designed in one piece as a so-called pendulum rudder or in two parts consisting of a fixed fin 6 and a movable rudder 7.

With the appropriate design of the sail and the tail unit area ratio, Position of the sail axis, lever arm of the tail unit - the tail unit maintains the angle of attack of the sail regardless of appearance wind direction and strength constant within a narrow range, regardless of the changes in the direction of travel of the Vehicle. The size and direction of the angle of attack of the sail 1 is determined by the Angle between sail and tail unit 2 is determined.

The setting of the sail 1 is therefore indirect through the adjustment made of the tail unit 2 against the sail 1, which has the advantage, that smaller forces have to be applied because of the smaller surface area, than with direct control of the sail.

By limiting the maximum deflection angle of the tail unit avoid that the sail 1 itself with a too large angle of attack with a torn off Current is driven.

Fig. 2 The most favorable angle of attack of the sail i changes with it the angle of the apparent wind Ws to the direction of travel F of the vehicle, since der'Winkel g between the air force resulting R and the vehicle's longitudinal axis L according to Fig. 2 for small Wind angles ß and large angles of attack d is about 900.

It is therefore advisable to reduce the angle of attack O.

With clear wind, however, the angle of attack should be as coarse as possible.

When turning, i.e. when passing through the angle of incidence of wind oO should the angle of attack should also be 0 ° in order to avoid heeling forces on the sail.

After turning, the set angle # of the tail unit must have its sign change to account for the wind coming in from the other side of the sail.

It is therefore advantageous that the proposed arrangement allows the optimal course of the angle of attack a of the sail 1 depending on its angular position to the vehicle axle through automatic assignment of the angle of attack (> of the sail to the blowing direction P depending on its angular position g to the vehicle to automatically establish a control.

In principle, such a control works as follows: Fig. 3 In addition to the rudder to control the route, the driver of the vehicle carried out the conventional ' can be, to control the sail, a lever 11, the axis of rotation 12 is expedient is perpendicular to the longitudinal axis of the vehicle. He operates the tail unit 2 via a Control 20 so that when the lever 11 is moved in the direction of travel forward the angle of attack of the sail is adjusted so that the air force of the sail a Component ahead in the direction of travel.

In the middle position, the sail has in every position to the longitudinal axis of the vehicle the angle of attack 0, so no air force acting across the sail.

When the lever 11 is moved against the direction of travel, the angle of attack is steered in the negative direction, the sail acts to the rear, i.e. it brakes the Drive or let the vehicle drive backwards.

With the deflection of the lever 11, the force on the sail can be between zero and the maximum force given by the wind speed, possibly still influenced can be steered from the sail position, forward and backward. The reverse the deflection angle of the tail unit is in the linkage between lever 11 and the tail unit performed.

The tail angle and thus the angle of attack of the sail become determined by the cam ring 21, which is arranged around the spar stub 12 and with the Vehicle is connected. The circumference 22 of the cam ring is shaped so that the linkage 23 is moved by the rollers 24 scanning the cam ring so that the Ku, rbelschleif 27 the tail unit 2 in the middle position of the sail to v "-n and rear without deflection is and the rashes of the tail unit when changing the sail from reverse their direction from one side to the other.

The lever 11 acts on the rocker arm 25, which leads to the tail unit Bumper 26 in the crank loop 27 leads so that the stroke of the bumper from can be adjusted full + over 0 to full.

By the slider crank 27 it is achieved that in every position of the Sail an adjustable part of the optimal angle of attack on the lever kl the definition in the cam ring is adhered to.

The rigid sail described can, apart from a precise setting of the most favorable angle of attack, be significantly improved in that it rests on the vehicle without a gap. In this way, in the case of watercraft, a flow around the lower edge of the sail is completely prevented, in other vehicles this forms an end disk that at least hinders the flow around. With this construction, which can be carried out according to Fig. 4, the induced resistance is reduced by half, depending on the completeness of the termination.

Since the sail revolves fully, the connection surface is expediently one Circular area, e.g.

can be formed by das'Kajtendeck.

The previous rigid sail proposals were influenced by the conventional sailing, made a lot of suggestions for rescue and recovery, This actually turns the rigid sail into a strong one.

ribbed normal sail with possibly 2 surfaces, so more spatial Education.

All rigid sails proposed so far therefore have the property / that they result in a relatively poor and rough surface of the sail and thus the main advantage of the fixed sail question the aerodynamic goods. at Almost all vehicles are salvaged from a perfectly circumferential angle-free The sail does not require the resistance of the sail even in extremely high winds is hardly larger than that of the conventional mast with standing and moving rigging, E.g. at 40 m / sec wind approx. 1 kp / m2, Since the sail rotates around 3600, the vehicle can also specify, it does, however, need the space to revolve around the tail unit.

When not in use for a long time, the sail is saved as a whole Tilting around the main fitting 8 9 or around a special tilting axis according to Figure 5.

For vehicles that are to be heavily over rigged, a reduction in size is required the sail area is desirable in strong winds, as it increases the performance of the sail is improved in strong winds. This can be done with the profile variant according to Figure 5, at.

which the profile is strongly indented - and consists of only one surface. This thin sail surface 30 can be drawn in relatively easily.

Fig. 6 For this purpose, the leading edge 31 of this sail surface 30 is placed on double links 32, which can be operated e.g. via a locker 33.

A rigid sail with a symmetrical profile does not achieve the thrust coefficients which can achieve a curved profile.

Two measures can be used for the curvature: 1. Curvature of the End of profile, 2nd curvature of the profile nose.

Measure 1 is easier to achieve than measure 2, which is for clean Execution requires some effort, but is of little use without proper experience.

Fig. 7 For measure 1, those known from aircraft construction are used Wingtip suitable; are known also measures for continuous Curvature of the profile b6.

Measure 2 requires more effort, but has a more favorable effect with regard to the achievable thrust coefficient with a favorable drag coefficient.

The nose 40 of the sail 1, shown in section in Fig. 8, consists from a movable core 41, which is about a fixed axis of rotation on the spar 13 of the sail 42 is pivotable to both sides of the profile. The front circumference 43 of this nose 40 forms the foremost part of the sail profile near the axis of rotation. At this Point 44 is an elastic tongue 45 of the fixed part of the wing profile auf.wnd forms the transition to the fixed part in all positions of the movable part 40.

To improve weather resistance, the entire nose of the profile is used an elastic cover 46 is placed, which mainly covers the gaps 47 on the tongues 45 - covers which is the most critical part of this arrangement.

The optimal curvature of the profile is over the angular range of the sail not equal. In both The curvature must go through the middle positions Zero in opposite weighting is given. At high wind speeds it can they be smaller than at low, because the high air speed also at low Shear force coefficient generates large forces at the beginning.

nei.inigsn Koromissen can therefore make the wing nose 40 of the same Control 20 and the bumper 26 are operated like the tail unit 2. For special high demands, however, the plow nose can be operated by a second control, which is influenced with a lever similar to the lever 11.

In principle, there is no size limit for the rigid sail described above. Because of the larger tail force, however, it is advisable to use the leading large sail Werk not to be connected directly to the controller 20, but to the bumper 27 to drive a Flettner rudder 29, which adjusts the tail unit.

It is also possible to have direct control on part of the To let the tail unit act as well as the Flettner control on the other, what at very large sails the manual control facilitates without having to look for the whole tail unit to have to forego direct influenceability.

Fig. 10 This control of the tail unit is also a useful safety control for power-controlled sails on very large vehicles.

The 'previously described sail with a tail unit on a tail unit beam is less suitable for multi-sail arrangements, because 'the tail unit through its large turning circle forces a large mast spacing and thus reduces the sail area or to increase the sail height. However, this increases the weight required for the sail area, since the bending moments on the sail as the sail height increases and grow on the vehicle.

For multi-sail arrangement according to Art, the conventional Yawl, Ketsch and especially schooner types. the sail without a tail unit is more advantageous. To do this, offers the concept of the flying wing, which, as with the flying-only aircraft, is Profile shape forms an inherently stable wing as a sail, whose tail unit 1, for example sits as a flap directly in the rear aunt of the sail.

This sail can be used to upgrade a multi-sail vehicle, its Sails themselves into the correct mutual position (twisting of the sails) set, using the same control is applied as with Application of the tail boom. One disadvantage of this sail shape is one property the profiles required for inherently stable sashes: your maximum thrust coefficient lies deeper than that of normal profiles and cannot be extended so far due to the curvature increase as with these. However, there are high shear coefficients at high angles of attack Rigid sails are important for sailing downwind, so that the sail with tail boom has its justification for individuals regardless.

The advantage of the fixed sail for the multi-sailer is its better efficiency. The smaller upwind angle improves cruising performance.

By eliminating the equipment, the sails are unsuccessful for mounting sails easier to assemble, the automatic adjustment makes it easy to maneuver better. The air force on the sail can be adjusted quickly and easily, it can be relative can simply be regulated in such a way that a certain incline is not exceeded.

The freedom of movement of the individual sails allows optimal gust adjustment of each individual sail, which always has the set air force regardless of the location Respects the wind direction and strength.

A control to maximum inclination is also feasible for example by a pendulum 50 or a physically equivalent arrangement can be done. Such a control is shown as an example in Figure 11.

The pendulum 50, which is fixedly mounted in the vehicle in 51, which also for example can be hydraulically damped, moved over the sliding blocks 55 and the loops 52 the rods 52 so that when one is reached by the stops 54 ein'stellbren Bank of the vehicle this connecting rod 57 of the crank loop 56 on smaller Itub is adjusted. This reduces the effect of the linkage 23 and thereby the tail deflection and, via the angle of attack, also the sailing force is reduced. The spring 59 brings the connecting rod 57 back into the old position at the end of the crank loop 56 when the stop of the pendulum 50 has decreased.

The same arrangement can also be used around the transverse axis for small vehicles use against overturning to the front. The same system allows it, by permanent Intervention of the pendulum to keep the bank inclination constant, so in the sense of a To act roll damping. In relation to the einæuhaitonde transverse position, endanger the maximum sailing power without manual actuation even in gusty winds.

It is still possible to adjust the feathering position by automatically influencing the lever 11 or the downstream linkage to make dependent on the sailing force itself. This is particularly useful for larger multi-sail craft, in which the transverse 'inclination' does not provide sufficient information about the load on the individual sail, which can be overstrained by a local gust. By a force measurement z, B. in the spar stub 12 and an electronic conversion of this measurement into the movement of a servo control, the control of the sail can be influenced in the direction of a smaller force. Such a device avoids breakages due to overloading, without the weight expenditure that would cause all parts to be designed for the maximum possible forces.

- patent claims -

Claims (22)

A n p r ü c h e Rigid sail for sailing vehicles, thereby g e k It is noted that there is a fixed position that cannot be influenced by the forces of the air Profile outline and full circumferential adjustability, with its position to the apparent Wind is controlled by an auxiliary wing (2) as a tail unit. 2. rigid sail according to 1, thereby g e k e n n n z e i c h n e t that the auxiliary wing (2) serving as a tail unit is attached to a tail unit carrier (3) is, 3. Rigid sail according to 1, characterized in that the tail unit is controlled by a controller (20) as a function of the angle of incidence of the wind, that the most favorable angle of attack of the wing profile is always maintained. 4. Rigid sails according to 1 to 3, thus no indications that the control (20) by a hand control with the lever (11) for Segcllcraftheeinflussung can be adjusted so that the angle of attack from the position-related maximum over Zero is reached up to the negative maximum value. 5. Rigid sail according to 4, thereby g e k e-n n n z e i c hn e t that the Position-dependent angle of attack control by means of a cam ring fixed to the vehicle is effected, the profile of which is shaped according to the desired angle of attack is that the tail unit (2) receives the appropriate position via a linkage. 6. Rigid sail according to 5, thereby g e k e n n n z e i c hn e t that im Linkage between cam ring and tail unit the translation between +1 over 0 to -1 can be adjusted by hand using a lever arrangement. 7. Rigid sail according to 1 - 4, thereby g e k e n n n z e i c hn e t that the angle of attack adjustment is effected by a ring fixed to the vehicle, and by Inclination of the ring around an axis transverse to the axis of rotation of the Segeid between positive and negative maximum value can be adjusted. 8. Rigid sail according to 1 - 7, thereby g e k e n n n z e i c hn e t that the sail profile has devices for arching the profile center line. 9. Rigid sail after 8, thereby g e k e n n n z e i c h n E that the Profile curvature is produced by curving the profile nose, with a movable front part (41) is threefold about a fixed axis (42) and together with resilient tongues (45) forms the archable profile outline. 10. Rigid sail according to 9, thereby g e k e n n n z e i c hn e t that an elastic waterproof cover (46) covers the archable nose to the outside. 11. Rigid sail after 8, thereby g e k e n n n z e i c n e t that the Profile line in the rear of the profile is arched, using conventional means used in aircraft construction. 12. Rigid sail after 8 to 11, thus not showing any signs t that the profile curvature is controlled depending on the sail position, where a similar control as for the tail unit, the camber manually or automatically adapts to the wind strength. 4 13. Rigid sail according to 12, characterized in that the same device is used to control the curvature as for the adjustment of the tail unit. 14. Rigid sail according to 1 to 13, which means that there are no indications t that the tail unit is controlled indirectly by a Flettner rudder, the Flettner rudder adjusted by the device for adjusting the tail unit according to claims (2) to (6) will. 15 ". Rigid sail after 14, not indicated by the fact that the tail unit is divided and one part directly and the other part via a Flettner rudder is controlled. -16. Rigid sail according to 1 to 15, therefore no signs t that a so-called inherently stable wing profile is used, with the tail unit on a much smaller lever arm, e.g. as in a flying wing aircraft, on the trailing edge of the wing can be attached. 17. Rigid sail after 16, g e k e n n n z e i c h n e t «by his Arrangement according to the type of? Awl, X.etsch and schooner sails. 18. Rigid sail according to 1 to 17, thus not showing any signs t that its lower edge connects to a mating surface of the vehicle with a minimal gap. 19. Rigid sail after 18, which means that it cannot be used. c hn e t that the gap is closed by an elastic formation of the sail edge, that the movement of the sail is not hindered even when ice forms .. 20, Rigid sail according to 1 to 19, therefore no markings t that by influencing the control 820 by a pendulum (50) or physically Equivalent arrangement, the inclination of the vehicle is limited. 21 Rigid sail after 20, noting that the inclination control is used in the sense of a slide control. 22. Rigid sail according to 1 to 21, thus not showing any signs t that the tail deflection is influenced by a sail force measurement in such a way that that a maximum sailing force is not exceeded. L e r s e i t e