Patent Publication Number: US-2018045178-A1

Title: Air Capture Turbine

Description:
FIELD OF THE INVENTION 
     The present invention is related the technical field of vertical axis wind turbines, and in particular to an air capture turbine with baffles for controlling the flow of air into and out of the turbine. 
     BACKGROUND OF THE INVENTION 
     Vertical axis wind turbines are well known and are considered to be more effective in regions of turbulent wind than horizontal axis wind turbines. For this reason it is believed that vertical axis wind turbines can be used effectively in built up areas. However, vertical axis wind turbines have the disadvantage that whilst air travelling in a certain direction will exert a force on, the turbine that tends to cause the turbine to rotate in a first direction, that same air will also exert a force on other parts of the turbine resisting rotation of the turbine in the first direction. 
     One solution to the above-mentioned problem is to encase the turbine in a cowling, which permits entry of wind to drive the turbine but prevents wind that would resist rotation of the turbine from impinging thereon. One such device is described U.S. Pat. No. 7,235,893. In this device a squirrel cage fan is mounted on a central shaft and a cowling that partially covers the squirrel cage fan is also mounted on the central shaft. The open part of the cowling is positioned with respect to the squirrel cage by a wind vane extending from the cowling. The squirrel cage is supported on a buoyant hull (it is intended that the whole device be supported on a body of water) which also functions as a flywheel. Drive rollers are in frictional engagement with the outer wall of the hull and deliver power to electrical generators. 
     Another example is found in DE3913948. This document describes a vertical axis turbine having a wind guard, which in common with the device described in U.S. Pat. No. 7,235,893 is positioned by a wind that is connected to the guard. The vertical axis turbine is mounted on a support tower. A central shaft which extends through the support tower delivers power to a generator located at the base of the tower. 
     U.S. Pat. No. 6,270,308 describes a wind turbine that comprises both a turbine rotating about a horizontal axis and a turbine rotating about a vertical axis. The turbine that rotates about a vertical axis rotates about the support tower and is provided with a fairing that provides an air inlet and an air outlet. The fairing prevents wind that would act against rotation of the turbine from impinging thereon. The rotational energy of the vertical axis turbine is converted into electricity by generators. The generators sit to the outside of a bearing ring attached to the underside of the vertical axis turbine. The generators may be powered by frictional engagement with a wall of the bearing ring or the bearing ring may be constructed so that its inner face carries a toothed wheel, with a corresponding toothed wheel being connected to the generator. 
     The bearing ring is supported by bearings, each of which includes a wheel oriented at 45 degrees aura which is mounted on ball bearings. The fairing is also mounted on bearings so that the inlet thereof may align with the prevailing wind. 
     It would be desirable to provide an improved turbine. 
     It would also be desirable to provide a turbine that is configured for carbon capture. 
     SUMMARY OF THE INVENTION 
     According to a first aspect of the invention there is provided an air capture turbine comprising a centrifugal fan having a plurality of fan blades and a wall from which the blades extend, and a cowling having an inner wall, the centrifugal fan housed to the inside of the inner wall of the cowling, wherein the centrifugal fan has a ring gear mounted on a lower side thereof, the turbine further comprising at least three energy converters, each including a gear wheel for engaging the ring gear, wherein the weight of the centrifugal fan is supported by the at least three energy converters, and wherein the inner wall of the cowling has a plurality of openings formed therein and closure members for selectively closing one or more of the plurality of openings, the openings providing for ingress and egress of air flowing in the direction of a prevailing wind to and from the centrifugal fan and the closure members protecting fan blades moving towards the direction of the prevailing wind from being engaged by air moving in that direction. 
     It is preferred that each opening in the outer wall is provided with guide members for guiding air to the opening, the guide members each presenting a larger opening than the said openings. 
     Advantageously, each opening is provided with a door which is moved between open and closed positions to open or close the opening with which the door is associated. 
     Preferably, the door may partially open the opening with which it is associated. 
     Preferably, the door is a sliding door. 
     Advantageously, the or each door slides in a space between the inner wall of the cowling and inner edges of the guide members. 
     Preferably, there are at least five openings. 
     Preferably, the energy converters are electricity generators 
     Advantageously, the ring gear and the gear wheel of the energy converters are bevelled, thereby centralizing the ring gear with respect to the gear wheels. 
     The air capture turbine may comprise a plurality of centrifugal fans mounted one on top of another. In such an arrangement one or more centrifugal fan may be provided with a ring gear on its upper side, said gearing for meshing with the ring gear of the lower side of another centrifugal fan. 
     In another embodiment the turbine includes or is attached to carbon capture means. Preferably, the or each opening is associated with a carbon capture means. Diverter means may be provided to divert a flow of air to or from the turbine to the carbon capture means. 
     According to another aspect of the invention there is provided a method of capturing carbon comprising the step of passing air egressing and/or egressing an air capture turbine according to the first aspect of the invention through a carbon capture system. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       In the Drawings, which illustrate preferred embodiments of an air capture turbine according to the invention: 
         FIG. 1  is a schematic plan view of the turbine: 
         FIG. 1 a    is a schematic side view showing a detail of the turbine; 
         FIG. 1 b    is a schematic representation of an alternative form of a component of the turbine: 
         FIG. 2 a    is a schematic representation of the fan of the turbine illustrated in  FIG. 1 ; 
         FIG. 2 b    is a schematic representation of an alternative configuration of fan of the turbine illustrated in  FIG. 1 ; 
         FIG. 2 c    is a schematic representation of another alternative configuration of fan 
         FIG. 3  is a schematic representation of the cowling of the turbine illustrated in  FIG. 1 ; 
         FIG. 4  is a schematic representation of the turbine in a first, configuration; 
         FIG. 5  is a schematic representation of the turbine in a second configuration; 
         FIG. 6  is a side view of a ship equipped with turbines according to the invention; 
         FIG. 7  is a side view of another ship equipped with turbines according to the invention; 
         FIG. 8  is a side view of a building having a number of turbines according to the invention mounted thereon; and 
         FIG. 9  is a side view of a cargo ship equipped with turbines according to the invention. 
     
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     Referring now to  FIGS. 1 to 3 , the turbine comprises a cowling  1  in which a centrifugal fan  5  sits The cowling  1  has are inner wall  2  having a plurality of openings  4  therein. The cowling includes upper and lower wails  8 ,  6  and wind guides  7  which comprise first and second walls  8 ,  9 . An inner edge  8 ′ of the first wall  8  and the inner edge  9 ′ of the second wall  9  terminate towards the inside of the cowling. A space  11  is formed between the inner edges  5 ′,  9 ′ of the walls  8 ,  9  and the inner wall  2  of the cowling. Each opening  4  is provided with a sliding door  10 , which is situated in the space  11 . 
     As can be seen from  FIG. 2 , the fan  5  comprises upper and lower ring beams  5   a ,  5   b  between which fan blades  5   c  extend. The lower ring beam  5   b  is provided with teeth  5   d , the lower edge of the ring beam  5   b  therefore forming a ring gear. The fan  5  is supported by a plurality of electricity generators  20 , each provided with a small gear wheel  21  mounted on a shaft of one of the generators  20 , best shown in  FIG. 1 a   . As can be seen fro  FIG. 1 , in the illustrated embodiment, the fan  5  is supported by seven generators  20 . By providing a multiplicity of generators  20  it is possible that the fan  5  may be supported by the generators without additional bearing supports. 
     The teeth of gear wheel  21  and the teeth  5   d  of the ring gear may be bevelled, for example at 45 degrees, as shown in  FIG. 1 b   . This has the advantage of self-centering the fan  5  on the gear wheels  21 . Where the teeth of the gear wheel  21  and the ring gear are not bevelled other means to centre the fan  5  within the cowling  1  must be provided. For example, a plurality of rollers may be mounted on the underside of the lower wall  6 , the rollers configured to engage the side of the ring beam  5   b.    
     The generators  20  are supported by a suitably specified frame  25  which includes legs  25 ′. 
     Referring specifically to  FIG. 4 , it will be appreciated that wind entering the opening  4  will exert a force on the blades  5   c  and that such a force will cause the fan  5  to rotate about its centre axis. Meshing of the gear teeth  5   d  of the ring gear with those of the gear wheel  21  mounted on a shaft which powers the generator  20  will cause that shaft to rotate and hence the generator  20  to generate electricity. 
     The cowling  1  provides only one path for entering the cowling. Wind enters the turbine through those openings  4  on the windward side of the cowling  1  that are open, with a corresponding number of openings  4  on the leeward side of the cowling also open. As discussed above, the openings  4  are opened or closed by sliding the doors  10  in the space  11 . The turbine may include actuators and control means for opening and closing the doors  10 , and control of which doors  10  are open and which are closed may be controlled automatically according to the direction of the prevailing wind. 
     It is known that when wind speeds exceed a certain threshold it is necessary to shut down a wind turbine. In the present invention this may be achieved by closing all the doors  10 . However, by providing for the control of air through the turbine, it is possible that the turbine may be allowed to run when wind speeds exceed the threshold at which it would normally be considered necessary to shut down the turbine. This is because it the doors may be partially closed to throttle the flow of air into and out of the turbine. In such a circumstance, the doors  10  that would be closed due to the direction of the prevailing wind would be closed, and the doors  10  that would be open would only be partially open. 
     It may be advantageous to reduce the load on the generators  20 .  FIGS. 2 b  and 2 c    illustrate fans  5  adapted to reduce the load on the generators  20 . The fan blades  5   c  lie at an angle to the vertical. Hence, wind encountering the fan blades will exert forces on the fan  5  having horizontal and vertical components. The vertical force component will tend to lift the fan  5 , thereby reducing the weight to be supported by the generators. Of course, this reduces the amount of force available for rotating the fan  5  and hence reduces the amount of electricity that can be generated by the turbine. Alternative means of lifting the fan may be provided. For example, magnets or electro-magnetic forces may be used. 
     The turbine of the invention confines the air used to rotate the fan, that is all the air driving the fan  5  enters and leaves the cowling  1 . This air entering and/or leaving (most suitably leaving) the turbine of the invention may therefore be passed through a carbon capture system. Any carbon capture system used for extracting carbon from a body of air may be utilised. 
       FIGS. 6 to 9  show the turbines  30 ,  30 ′ of the invention mounted on ships  31 ,  32 ,  34  and on a building  33 . The turbines  30  mounted on the ships  31  and  33 , and on the building  33  are stacked one on top of the other. In this arrangement the lower turbine is a turbine of the type shown in  FIGS. 1 to 5 . The turbines  30 ′ mounted on top of either the turbine  30  or another turbine  30 ′ differ may slightly. In the turbines  30 ′, instead of the fan  5  being supported on the generators  20 , it is supported by the bearing ring  5   a  of the fan  5  of the turbine on which it sits. In this configuration the bearing ring  5   a  is provided with teeth in a similar manner to the lower bearing ring  5   b . Such gear teeth of the ring  5   a  may also be bevelled so that the fan  5  of the turbine  30 ′ remains centralised on the fan  5  of the turbine  30 . In  FIG. 8 , where there are two turbines  30 ′, the upper ring gear  5   a  of the first turbine  30 ′ should also be provided with gear teeth to mesh with the gear teeth  5   d  of the fan  5  of the upper most turbine  30 . 
     The cowlings  1  of the turbines  30 ,  30 ′ may be bolted together, or other fastening means or constraining means may be provided so that the said cowlings  1  of the respective turbines do not move with respect to one another. 
     The turbine of the invention overcomes the problem of the driving wind actually slowing down the turbine, and does so with few moving parts. In fact where the fan  5  is supported on the generators themselves much power transmission gear may be omitted. The turbines may be used on ships and buildings to provide power close to the point of consumption.