VERTICAL SHAFT WIND TURBINE WITH DIFFUSER

Abstract: The present invention relates to wind turbine with a rotor (1, 12, 18, 32, 36) according to the Darrieus principle, for example, placement on apartment and office buildings, in which the rotor can be placed in a housing concentrator (29, 33, 37).

Description: VERTICAL SHAFT WIND TURBINE WITH DIFFUSER The present invention relates to a device for discharging wind energy into electric energy, in which in this case it concerns wind turbines for use in built-up areas, in which on a vertical shaft on radial distance wing-shaped blades are applied, so that by means of wind energy as a wind stream lift power can be generated on the mentioned wing-shaped blades, through which the mentioned vertical shaft can be brought to rotation and through that an electronic generator can be activated. A wind turbine constructed as a vertical shaft is known in the Canadian Patent document number 1 294 220, titled: 'Wind Turbine", of Obidniak, Louis and Sambrabee Inc., Canada, put onto the market under the name CATAVENT. Here, it concerns a runner type wind turbine designed to utilize energy from low speed stream. This turbine has a turbine disc which deflects and discharges a wind stream in radial and parallel directions relative to the disc blades and so it provides a propulsion in which rotor constructions are developed, which allow the disc and its power shaft to be arranged and assembled in a vertical or a horizontal position. The vertical shaft arrangement is preferred. The turbine includes a disc, mounted on a shaft located in central guides affixed to an outer stationary turbine stand. The disc mounts a plurality of air blades shaped in such a way that the incoming air impinges on the blades radially, circumferentially and outwardly relative to the turbine disc. Furthermore, the blade is shaped in a special way as a hollow tapered body (figure 3B of said patent document) , which has a longitudinal axis and tapers from the inlet to the outlet and has a cross-section decreasing longitudinally along said axis, and in which the blade is supplied with means for connection to the axis of said hollow tapered body at an angle of said flow of air to the blade. Figures 4A, 4B and 5A of said patent document further indicate the mechanical working of the blade, shaped in a special way. This shows that, in case of a proper operation a tangential driving air stream on the blades must be created, through which this rotor blade should give a reasonable power output at a relatively low tip speed. Herewith the coupling coefficient should also be high during an ideal operation of the turbine disc with said blades, in which on the ends special upwardedly bended blades have been applied. Furthermore, a housing or concentrator is indicated in the shape of a straight tube or preferably a tube bend of 90° to stabilize and/or improve the working/operation. Further the turbine rotates towards the direction of the air stream in order to be a wind finder. The turbine rotates with the wind around the vertical shaft. The working is summarized as follows: - the housing directs itself towards the wind or air stream in such a way, that, in theory, the inlet of the housing or concentrator is always faced towards the wind; - in theory, the wind or air stream is discharged from a horizontal direction to a vertical direction into the rotor; and - the wind or air stream can escape out of the rotor through the blades, that create a tangential outflow along the circumferential of the turbine disc, through which the power is created that rotates the rotor. The known aforementioned wind turbine has, after varied tests in practice, a number of disadvantages with regard to stability and/or swaying of the device when searching the wind direction, with that the turbine disc or rotor has a bad yield, which is approximately half the output mentioned in the patent document. The bad yield is caused by the so called resistance rotor type with the maximum theoretical output of 18^%. According to the statement the output of the CATAVENT turbine with housing should go to an output of 50%, but from the said tests in practice this seems to stop at approximately 25%. Further a wind turbine constructed as a vertical shaft according to the Darrieus principle is known in the American patent document number 3 918 839, titled: 'Wind Turbine" of Bennie F. Blackwell, Louis V. Feltz and Randall C. Mayden from Albuquerque, New Mexico. Here, as mentioned, it concerns a vertical wind turbine with on radial distance of the vertical shaft wing-shaped blades roughly connected according to a parabola in straight lines and so form a Darrieus rotor type. The rotor according to the Darrieus principle is not self-starting. For starting, two small starting rotors are applied on the vertical shaft to start the large rotors according to the Darrieus principle (figures 7 and 8 of the mentioned patent document) . The cross-sectional profile of the longitudinal parabolic shaped wings is a NACA 0012 profile and has a smoothly constructed surface. Furthermore, the vertical shaft is guyed in order to give the whole sufficient rigidity against deformation and collapsing. This described vertical shaft wind, turbine also has a number of disadvantages, such as the bending slack wing- shaped blades with a partly parabolic longitudinal axis, which are connected on strips making a straight line, which in their turn are connected to the mentioned vertical shaft, which drives the generator, and when standing still hang down relatively 'slack" and according to the drawing should stand wide out in order to create a reasonable power during operations. The possible deformation is relatively high at a lighter construction with a higher or interesting power. A further disadvantage is, that the vertical mast or shaft must be guyed, which hinders the use in an urban surrounding. Finally, the starting rotors are relatively voluminous, costly in production and act as a brake when the rotor according to the Darrieus principle is up to speed, which is undesirable. The aim of the present invention is to provide an improved wind turbine in which the aforementioned disadvantages are solved or much less and of which the working is much better and the hindrance much less and all of this with an economic favourable price of the vertical shaft wind turbine. For this the improved vertical shaft wind turbine is further developed in such a way, that the mentioned wind turbine is a rotor consisting of, on a radial distance R of a vertical shaft almost raised tangential applied wing- shaped blades over a height of approximately H and therefore provides a rotor according to the Darrieus principle, which rotor with almost vertical shaft can be placed in a housing as concentrator, in which the wall of the housing in longitudinal direction has a wing-shaped cross-section also, in which the opening of the mentioned concentrator facing the wind has a smaller surface than the opening which is turned away from the wind, in which the mentioned wing-shaped blades in their longitudinal direction can have an approximate helical shape, in which special means can be utilized when starting up, in which the high speed λ of the rotor in use with regard to the utilized rotor blade profile is such, that no 'stall" appears and under that condition the power production is at its maximum and can roughly be between approximate 2 and 8. The advantage or result is a smoothly running very strong improved wind turbine, of which the mentioned disadvantages of the known and mainly in the introduction described wind turbine according to the Darrieus principle are solved, in which the rotation of the rotor is not experienced as visually objectionable, in which the working/power production of the rotor can be improved by using the mentioned housing in the form of a concentrator and in which no cable twist with the discharge cable can occur. Furthermore, the device according to the invention is further developed in such a way, that the mentioned radial distance R of the vertical shaft of the wing-shaped blades to the central shaft is almost constant, in which the longitudinal shaft of the mentioned wing-shaped blades makes an angle with the vertical, which angle a lies between 5 and 45 degrees, in which the mentioned uneven quantity of wing-shaped blades is preferably 3 or more. The advantages are an almost vibration free run of the rotor, in which the wind catch and/or the lift of the wing- shaped blades is almost constant over the whole vertical length and the tip speed is determined optimally on theoretical basis. Then the device according to the invention is further developed in such a way, that the mentioned wing-shaped blades have, for example, a NACA profile, which are applied over mentioned height H, in which stacking of rotor elements with individual height H is possible, in which the connection in vertical direction of the mentioned wing- shaped blades can or should show a recede L. The advantage of this is, that by stacking the rotor elements according to the Darrieus principle with individual height H is possible, in which larger powers are realized in a simple manner. Furthermore the device according to the invention is further developed in such a way, that the housing of the concentrator has a rectangular cross-section, in which the upper and bottom surface can be left out, if necessary. The advantage of this is, that the housing of the concentrator can be constructed easier and therefore cheaper. The preferred construction of the invention will be described by way of example, and with reference to the accompanying drawing, in which: Fig. 1 shows a view in oblique perspective of a first preferred embodiment of the rotor according to the Darrieus principle according to the invention; Fig. 2 shows a view in oblique perspective of a second preferred embodiment of the rotor according to the Darrieus principle according to the invention; Fig. 3 ditto of a third preferred embodiment of the rotor according to the Darrieus principle; Fig. 4 shows a view in oblique perspective of the first preferred embodiment of the rotor of figure 1 placed in the housing, constructed as concentrator; Fig. 5 shows a view in oblique perspective of a fourth preferred embodiment of the rotor according to the Darrieus principle placed in the housing, constructed as concentrator; and Fig. 6 shows a view in oblique perspective of a fifth preferred embodiment of the rotor according to the Darrieus principle placed in a diffusor type concentrator (body of revolution) . Figure 1 shows a view in oblique perspective of a first preferred embodiment of the rotor 1 according to the further developed Darrieus principle according to the invention. The rotor has a vertical shaft 2, which drives the generator 3 for generating electricity, which generator in operation starts the rotor. In principle two discs 4 and 5 are fixedly mounted around the vertical shaft 2, which along the circumferential edges 6 and 7 together with a number of rings or discs 8, 9, 10 are interconnected by almost tangentially applied wing-shaped blades 11, which with their wing shape are almost raised tangentially applied, over a total height H, so that the total rotor 1 with a radius R in this way forms the Darrieus principle. In vertical sense, between the applied wing-shaped blades 11 a recede L can or should be applied to minimise the vibrations . Figure 2 shows a view in oblique perspective of a second preferred embodiment of the rotor 12 according to the invention according to the Darrieus principle. The rotor 12 again has a vertical shaft 13, which also drives a generator 14 as in figure 1. Also on this shaft 13 two round discs 15 and 16 are mounted, which discs along the edges are interconnected with wing-shaped blades 17, which with their wing shape are applied almost raised tangentially, in order to form again a rotor according to the Darrieus principle. The total height of the rotor element 12 is also indicated with H and the radius with R. Figure 3 shows a third preferred embodiment of the rotor 18. The construction is almost the same as in figure 1, with the discs 19 and 20 on a vertical shaft 21 and along the ring shaped edges 22, 23, 24, 25 and 26 the tangentially applied wing-shaped blades 27, so that again a rotor element according to the Darrieus principle is created, connected to an electricity generator 28. In vertical sense, between the applied wing-shaped blades 27 again a recede L can or should be applied. Figure 4 is the rotor according to the Darrieus principle of figure 1 placed in a housing 29, in which further the same relevant reference numbers are used as in figure 1. The housing 29 works as a concentrator for the added wind or air stream W, in which the opening 30 faced to the wind or air stream W of the concentrator is smaller than the opening 31 turned away from the wind or air stream W. Furthermore it concerns rectangular openings, as the developed rotor according to the Darrieus principle has a so called H-rotor. In figure 5 shows another embodiment of a rotor 32 according to the Darrieus principle, a so called H-rotor, placed in a thereon mounted housing, concentrator 33. The rotor 32 contains a shaft 34, in which the tangential mounted wing-shaped blades 35 are mounted on a distance R. The design of the housing or concentrator 33 has already been described in figure 4. Figure 6 shows another rotor 36 with a parabolic shape according to the Darrieus principle in a therefore adjusted housing or concentrator 37, constructed as a body of revolution. The wing-shaped blades 38 in parabola are mounted directly to the vertical shaft 39. Laboratory tests show that the said rotors 1, 12, 18, 32, 36 have an optimum high speed λ of approximately 4 and that the rotation of the rotor according to the Darrieus principle according to the invention, can be started with a generator with soft- starter or otherwise with, for example, a motor with small power, in which vibrations are highly eliminated by an uneven number tangential helical raised mounted blades 11, 17, 27, 35, 38. Due to the vertical shaft 2, 13, 21, 34, 39 of the rotor according to the Darrieus principle no cross system is necessary and cable twist is simply avoided. Finally it has to be emphasized, that the above description constitutes a number of preferred embodiments of the present invention and that further variations and modifications are possible without departing the scope of this patent description.

Claims: CLAIMS 1. Device for discharging wind energy into electric energy, in which in this case it concerns wind turbines for use in built-up areas, in which on a vertical shaft on a radial distance wing-shaped blades are applied, so that by means of wind energy as a wind stream lift power can be generated on the mentioned wing-shaped blades, through which the mentioned vertical shaft can be brought to rotation and through that an electronic generator can be activated, characterized in that, the mentioned wind turbine is a rotor (11, 12, 18, 32, 36) consisting of, on radial distance R of a vertical shaft (2, 13, 21, 34, 39) almost raised tangentially applied wing-shaped blades (11, 17, 27, 35, 38) over a height of approximately H and therefore provides a rotor according to the Darrieus principle, which rotor (2, 13, 21, 34, 39) with almost vertical shaft (2, 13, 21, 34, 39) can be placed in a housing as concentrator (29, 33, 37), in which the wall of the housing in longitudinal direction has a wing-shaped cross-section also, in which the opening (30) of the mentioned concentrator (29, 33, 37) facing the wind has a smaller surface than the opening (31) which is turned away from the wind, in which the mentioned wing-shaped blades (11, 17, 27, 35, 38) in their longitudinal direction can have an approximate helical shape, in which special means can be utilized when starting up, in which the high speed λ of the rotor (1, 12, 18, 32, 36) in use with regard to the utilized rotor blade profile is such, that no 'stall" appears and under that condition the power production is at its maximum and can roughly be between approximately 2 and 8. 2. Device according to claim 1, characterized in that, the mentioned radial distance R of the vertical shaft of the wing-shaped blades (11, 17, 27, 35, 38) to the central shaft (2, 13, 21, 34) is almost constant, in which the longitudinal shaft of the mentioned wing-shaped blades (11, 17, 27, 35) makes an angle α with the vertical, which angle lies between 5 and 45 degrees. 3. Device according toclaim 1, characterized in that, the mentioned uneven number of wing-shaped blades (11, 17, 27, 35, 38) is preferably 3 or more. 4. Device according to the aforementioned claims, characterized in that, the mentioned wing-shaped blades (11, 17, 27, 35) have, for example, a NACA profile, which are applied over mentioned height H, in which stacking of rotor elements with individual height H is possible, in which the connection in vertical direction of the mentioned wing-shaped blades (11, 27) can or should show a recede L. 5. Device according to claim 1, characterized in that, the mentioned radial distance R of the wing-shaped blades (38) to the central shaft (39) over the length of the central shaft can have a parabola shape (figure 6), in which the housing of the concentrator (37) can then have the shape of a body of revolution. 6. Device according to the aforementioned claims, characterized in that, the housing of the concentrator (29, 33) has a rectangular cross-section, in which the upper and bottom surface can be left out, if necessary, and in which the upper and bottom side of the rotor (2, 13, 21, 34) can then be closed. 7. Device according to claim 1, characterized in that, the mentioned means for starting up can be a generator with starter, or a motor with low power. 8. Device as claimed in aforementioned claims, characterised in that, the material of the wing-shaped blades can be a metal, such as aluminium or a plastic such as polyester and/or a composite material.

Inventors: SIDLER HENDRICUS FRANCISCUS AN, SIDLER MARTINUS ANTONIUS WALTH, SIDLER, HENDRICUS, FRANCISCUS, ANTONIUS, SIDLER, MARTINUS, ANTONIUS, WALTHERUS
Applicants: C O R E INTERNAT B V, SIDLER HENDRICUS FRANCISCUS AN, SIDLER MARTINUS ANTONIUS WALTH, C.O.R.E. INTERNATIONAL B.V., SIDLER, HENDRICUS, FRANCISCUS, ANTONIUS, SIDLER, MARTINUS, ANTONIUS, WALTHERUS
Application year: 2001
Main classification: F03D3
IPC codes: F03D3