U.S. patent application number 09/729884 was filed with the patent office on 2001-05-17 for system for providing wind propulsion of a marine vessel using a helical turbine assembly.
This patent application is currently assigned to NORTHEASTERN UNIVERSITY. Invention is credited to Gorlov, Alexander M..
Application Number | 20010001299 09/729884 |
Document ID | / |
Family ID | 23798094 |
Filed Date | 2001-05-17 |
United States Patent
Application |
20010001299 |
Kind Code |
A1 |
Gorlov, Alexander M. |
May 17, 2001 |
System for providing wind propulsion of a marine vessel using a
helical turbine assembly
Abstract
A helical turbine assembly capable of providing high speed
unidirectional rotation under a multidirectional ultra low-head
fluid flow is disclosed. The assembly comprises an array of helical
turbine units or modules arranged, vertically or horizontally, to
harness, for example, water or wind power. Each turbine unit or
module comprises a plurality of helical blades having an airfoil
profile. The modules for wind power may be mounted to rotatable
shafts supported by lightweight structures anchored by guy wires to
the ground. The helical turbine can also provide ship propulsion by
utilizing the power of ocean waves. In a further embodiment, a
cylindrical distributor is provided in the helical turbine to
channel the fluid flow to the blades of the turbine, thereby
increasing efficiency and power output. The helical turbine with
distributor may be used to lift or lower a body either being
submerged into a fast stream or dragged in the fluid. The turbine
may also include two or more rings of helical blades to increase
torque and power output.
Inventors: |
Gorlov, Alexander M.;
(Brookline, MA) |
Correspondence
Address: |
WEINGARTEN, SCHURGIN, GAGNEBIN
& HAYES, LLP
TEN POST OFFICE SQUARE
BOSTON
MA
02109
US
|
Assignee: |
NORTHEASTERN UNIVERSITY
|
Family ID: |
23798094 |
Appl. No.: |
09/729884 |
Filed: |
December 5, 2000 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
09729884 |
Dec 5, 2000 |
|
|
|
09524655 |
Mar 13, 2000 |
|
|
|
Current U.S.
Class: |
440/8 |
Current CPC
Class: |
F03B 3/00 20130101; F03D
3/061 20130101; F05B 2240/40 20130101; F03B 17/061 20130101; F03D
9/257 20170201; F05B 2240/215 20130101; Y02E 10/38 20130101; F03D
3/02 20130101; Y02E 10/30 20130101; Y02E 10/74 20130101; Y02E 10/28
20130101; F05B 2240/2212 20130101; F05B 2210/16 20130101; F03D
13/20 20160501; Y02E 10/20 20130101; Y02E 10/223 20130101; Y02E
10/728 20130101; F03D 9/32 20160501; F03D 3/065 20130101; F05B
2250/25 20130101; Y10S 416/06 20130101; F05B 2240/33 20130101 |
Class at
Publication: |
440/8 |
International
Class: |
B63H 009/00 |
Claims
What is claimed is:
1. A system for providing wind propulsion of a marine vessel,
comprising: a marine vessel having a propeller; and a cylindrical
helical turbine capable of unidirectional rotation under
multidirectional fluid flow and mounted to a deck of said marine
vessel and connected to a propeller, said helical turbine
comprising: a rotatable shaft mounted to said marine vessel to
extend upwardly from the deck of said vessel; at least one turbine
blade support member fixedly mounted to said rotatable shaft for
rotation therewith in a plane perpendicular to said shaft; and a
plurality of turbine blades having a fixed cylindrical helical
configuration mounted to said turbine blade support member for
rotation about an axis of said rotatable shaft, each blade having
an airfoil shape having a leading edge and a trailing edge and an
airfoil profile lying in a plane perpendicular to said shaft, each
of said blades fixedly mounted to said blade support member to be
radially spaced from said rotatable shaft for rotation in the plane
perpendicular to said shaft in the direction of said leading edge;
and a transmission interconnecting said helical turbine to said
propeller for providing rotation of said propeller.
2. The system of claim 1 wherein said helical turbine comprises a
plurality of helical turbine modules.
3. The system of claim 1 wherein said helical turbine is supported
by a structure anchored to said vessel by guy wires.
Description
CROSS REFERENCE TO RELATED APPLICATIONS
1. This application is a divisional of application Ser. No.
09/524,655 filed on Mar. 13, 2000, which is a divisional of
application Ser. No. 08/806,563 filed on Feb. 25, 1997, which is a
continuation of application Ser. No. 08/452,824 filed on May 30,
1995, now U.S. Pat. No. 5,642,984, which is a continuation-in-part
of application Ser. No. 08/241,762, filed on Apr. 22, 1994, now
U.S. Pat. No. 5,451,137, which is a continuation-in-part of
application Ser. No. 08/179,965, filed on Jan. 11, 1994, now U.S.
Pat. No. 5,541,138, the disclosures of all of which are
incorporated by reference herein.
FIELD OF THE INVENTION
2. This invention relates to turbines and more particularly to
turbines capable of unidirectional rotation under multidirectional
fluid flows for use with hydro-pneumatic, hydro, wind, or wave
power systems.
BACKGROUND OF THE INVENTION
3. A unidirectional turbine is a turbine capable of providing
unidirectional rotation from bidirectional or reversible fluid
flow, such as in tidal estuaries or from shifting wind directions.
Generally, three basic types of unidirectional reaction turbines
are known, the Wells turbine, the McCormick turbine, and the
Darrieus turbine.
4. The Wells reaction turbine is a propeller-type turbine that
comprises a series of rectangular airfoil-shaped blades arranged
concentrically to extend from a rotatable shaft, as shown in FIG.
1. Typically, the turbine is mounted within a channel that directs
the fluid flow linearly along the axis of the rotatable shaft. The
blades are mounted to extend radially from the rotatable shaft and
rotate in a plane perpendicular to the direction of fluid flow.
Regardless of the direction in which the fluid flows, the blades
rotate in the direction of the leading edge of the airfoils, which,
in FIG. 1, is counterclockwise.
5. The Wells turbine is capable of rapid rotation. The outer ends
of its blades move substantially faster than the flowing air,
causing high noise. Also, its efficiency is relatively low, because
the effective surface area of the airfoil-shaped blades is limited
to the outer tips, where the linear velocity is greatest. The
blades cannot capture a substantial amount of the available energy
in the fluid flowing closer to the shaft.
6. The McCormick turbine comprises a series of V-shaped rotor
blades mounted concentrically between two series of stator blades,
as shown in FIG. 2. The rotor blades are mounted for rotation in a
plane perpendicular to the direction of fluid flow. The stator
blades direct fluid flow to the rotor blades. To achieve
unidirectional rotation with bidirectional fluid flow, the outer
stator blades are open to fluid flowing from one direction, while
the inner stator blades are open to fluid flowing from the opposite
direction.
7. The McCormick turbine is more quiet and could be more efficient
than the Wells turbine. However, its rotational speed is too slow
for direct operation of an electric generator. Its configuration is
also complex and expensive to manufacture.
8. The Darrieus machine is a reaction turbine with straight
airfoil-shaped blades oriented transversely to the fluid flow and
parallel to the axis of rotation, as shown in FIG. 3. The blades
may be attached to the axis by circumferential end plates, struts,
or by other known means. In some variations, the blades are curved
to attach to the ends of the axis. A Darrieus reaction turbine
having straight rectangular blades, mounted vertically or
horizontally in a rectangular channel, has been placed directly in
a flowing body of water to harness hydropower. The Darrieus turbine
rotates with a strong pulsation due to accelerations of its blades
passing through the higher pressure zones in the fluid that lowers
the efficiency of the turbine.
9. Thus, a need still exists for a quiet, efficient, uniformly
rotational, simple, unidirectional turbine that can operate at high
speeds.
SUMMARY OF THE INVENTION
10. The present invention provides a unidirectional helical turbine
capable of achieving high speeds needed for industrial electric
generators. The turbine comprises a working wheel having a
plurality of airfoil-shaped helical blades mounted transversely to
the direction of fluid flow for rotation in a plane parallel to the
direction of fluid flow. The blades extend between two supporting
members, such as a pair of parallel discs, mounted on a rotatable
shaft. The blades rotate in the direction of the leading edge of
the airfoil, regardless of the direction of fluid flow.
11. The helical configuration ensures that a portion of the blades
are always positioned optimally with respect to the fluid flow,
thereby creating maximum thrust to spin the turbine. The continuous
helical blades provide a continuous speed of rotation uninterrupted
by accelerations and decelerations that accompany the Darrieus
turbine as the blades pass the least and most efficient thrust
zones. The skewed leading edges of the helical configuration
further reduce resistance to the turbine rotation. The helical
blades are operable with or without a channel to direct the fluid
flow.
12. In a further embodiment, a cylindrical distributor is provided
within the helical blades, to channel the fluid to the blades of
the turbine, thereby increasing the fluid velocity near the blades
and the power output of the helical turbine. The helical turbine
combined with the cylindrical distributor attached to the turbine
may also be used as an apparatus for lifting or lowering bodies
such as submarines or submersible barges.
13. The helical turbine may also be provided with multiple layers
or rings of concentrically arranged helical blades. The blades of
adjacent rings are shifted circumferentially such that they do not
overlap each other in the fluid flow. That is, the inner blades are
positioned within the spaces between the outer blades. The
multilayer arrangement increases the torque and power output.
14. In a case when the helical turbine is used with a
hydro-pneumatic energy converter, a channel interconnects a pair of
chambers in which air is alternately compressed and expanded due to
the alternate filling and emptying of the chambers with water. The
alternate compression and expansion causes the air flow to
alternate in direction through the connecting channel. The helical
turbine, mounted in the channel, is in this manner able to capture
the energy in the flowing air and convert it to rotary mechanical
energy. The turbine is connected to an electric generator for
generation of electrical energy. No additional gearing speed
increaser is usually required, since the turbine rotates fast
enough for conventional generators.
15. In a hydro application, the helical turbine may be mounted in a
vessel located in a current of about 5 feet per second or greater,
such as in a tidal channel. The turbine is located below the
surface of the water, where the current velocity is greatest, and
is retained in that location by virtue of the vessel's rise and
fall with the water. The helical turbine embodiment is particularly
suited to this application. A housing to channel the flow to the
turbine may by provided if desired, but is not necessary if the
current velocity is sufficiently great. The turbine is connected to
a suitable electric generator, which may be mounted on the vessel
in a water tight chamber. The turbine can also be used in
conventional applications, such as in dams.
16. The helical turbine is also efficiently configured in a modular
form comprising, preferably, two or more helical blades in spirals
extending from one end to the other. For wind power applications, a
plurality of modules is arrayed, vertically or horizontally, on
rotatable shafts which are supported by lightweight structures
anchored to the ground by guy wires. The optimally designed modules
provide unidirectional and uniform, non-oscillating rotation in any
non-zero angle between the turbine shaft and wind direction.
17. The helical turbine is also useful to provide propulsion or
supplement engine-driven propulsion of a marine vessel utilizing
the power of ocean waves. The helical turbine is operable under the
multidirectional oscillations of ocean waves and can develop a
substantial axial torque useful in the propulsion of marine
vessels.
DESCRIPTION OF THE DRAWINGS
18. The invention will be more fully understood from the following
detailed description taken in conjunction with the accompanying
drawings in which:
19. FIG. 1 is a schematic illustration of a prior art Wells
turbine;
20. FIG. 2 is a schematic illustration of a prior art McCormick
turbine;
21. FIG. 3 is a schematic illustration of a prior art Darrieus
turbine;
22. FIG. 4 is a cross-sectional side view of a helical turbine
according to the present invention;
23. FIG. 5 is a frontal view of a helical turbine according to the
present invention;
24. FIG. 6 is a cross-sectional view along line VI-VI of FIG.
5;
25. FIG. 7 is a cross-sectional view along line VII-VII of FIG.
5;
26. FIG. 8 is a schematic cross-sectional side view of a turbine
according to the present invention illustrating zones of thrust
efficiency;
27. FIG. 9 is a fragmentary view of a single turbine blade of the
embodiment of FIG. 5 illustrating resolution of the thrust force on
the blade;
28. FIG. 10 is a schematic illustration of the turbine of the
present invention in operation in a hydro-pneumatic power
system;
29. FIG. 11 is a perspective view of a system mounted on a
catamaran for harnessing hydro energy according to the present
invention;
30. FIG. 12 is a frontal view of the system of FIG. 11;
31. FIG. 13 is a side view of the system of FIG. 11;
32. FIG. 14 is a schematic view of a helical turbine module of a
further embodiment of the present invention;
33. FIG. 15 is a schematic view of an array of the turbine modules
of FIG. 14 arranged vertically;
34. FIG. 16 is a schematic view of an array of the turbine modules
of FIG. 14 arranged horizontally;
35. FIG. 17 is a front view of a further embodiment of a helical
turbine of the present invention embodying a cylindrical
distributor;
36. FIG. 18 is a cross-sectional side view of the helical turbine
of FIG. 17;
37. FIG. 19 is a side view of a marine vessel propulsion system of
the present invention;
38. FIG. 20 is a front view of the propulsion system of FIG. 19;
FIG. 21 is a schematic view of an array of turbines connected via a
transmission to a single generator;
39. FIG. 22 is a cross-sectional side view of a multilayer helical
turbine of the present invention;
40. FIG. 23 is a schematic front view of a multilayer helical
turbine of the present invention;
41. FIG. 24 is a schematic view of a helical turbine and
cylindrical distributor used to maintain flotation of a submerged
object by developing a lifting force;
42. FIG. 25 is an end view of the helical turbine and submerged
object of FIG. 24; and
43. FIG. 26 is a schematic view of a helical turbine as a wind sail
for a marine vessel.
DETAILED DESCRIPTION OF THE INVENTION
44. A helical turbine according to the present invention is shown
in FIGS. 4, 5 and 14. The turbine 10 comprises a plurality of
airfoil-shaped helical turbine blades 12 supported for rotation on
a rotatable shaft 14 by one or more turbine blade support members
16. The airfoil-shaped blades may be formed from any suitable
material, such as a steel or plastic material. The blade support
members 16, which, in the embodiment shown, comprise parallel,
circular discs, are fixedly mounted in spaced relation on the
rotatable shaft 14 such that rotation of the blades 12 and discs 16
causes the shaft 14 to rotate as well. The blades 12 are fixedly
mounted to extend helically from one disc 16 to the other disc 16
and are spaced radially from the rotatable shaft 14. The blade
support members may comprise other configurations, such as a single
central disc, radial spokes, or the like.
45. The turbine 10 may be free in a fluid flow or may be mounted
inside a channel 20 or duct. The channel, if provided, generally
comprises opposed side walls 22,24, a top wall 26, and a bottom
wall 28 which form a passage 30 for directing the flow of fluid to
the turbine. The shaft 14 is oriented transversely to the flow of
fluid through the channel and is mounted for rotation, for example,
via bearings in the side walls of the channel. Also, with the
helical configuration, it is possible to eliminate the channel
entirely if desired.
46. Each helical blade 12 has an airfoil shape with a leading edge
36 and a trailing edge 38 oriented transversely to the flow of
fluid. Preferably, the blades are formed with a suitable airfoil
profile, as is known in the art. The blades 12 are mounted at the
outermost diameter of the circular discs 16 and are generally
oriented to lie along a circle defined by the outer diameter of the
discs such that the chord of each airfoil generally but not
necessarily forms the chord of an arc of the circle. Any number of
blades may be provided.
47. Referring to FIG. 4, fluid flowing in the direction of arrows
40 along the channel 20 causes the turbine 10 to rotate in the
direction of the leading edge 36 of the blades as shown by arrow
42. Similarly, fluid flowing in the opposite direction along the
channel 20 also causes the turbine to rotate in the same direction,
the direction of the leading edge 36 of the blades 12. As is
apparent, the turbine rotates in a plane parallel to the flow of
fluid. The blades 12 should be spaced radially as far from the
rotatable shaft 14 as practicable to capture the greatest amount of
energy in the flowing fluid. The skewed leading edges 36 further
reduce resistance to the turbine rotation.
48. The helical blades may be divided into two halves 102a, 102b,
as shown in FIG. 5, in which one half is a left-handed helix and
the other half is a right-handed helix. In this manner, the
components of the thrust force which extend parallel to the shaft
14 cancel each other out, as discussed further below. However, all
left-handed or all right-handed helixes or any other suitable
helical configuration may be provided if desired. The blades are
fixedly attached at their ends to extend transversely from one disc
to the other disc, creating a non-solid, fluid transmitting
cylinder. In addition, any suitable number of radial spokes 110 may
be provided which extend perpendicularly from the rotatable shaft
to each blade at spaced intervals. Such radial spokes increase the
integrity and structural strength of the system. Alternatively, the
blade support members may comprise other configurations, such as a
single central disc, radial spokes alone, or the like.
49. In addition, a portion of the blades 12 are always positioned
in the most efficient zones of the fluid pressure, thereby creating
maximum thrust to spin the turbine. Two least efficient thrust
zones, near the top and bottom walls, and a most efficient thrust
zone, near the center, are depicted in FIG. 8 merely for
illustrative purposes. It will be appreciated that in actuality the
efficiency of the thrust varies continuously from a minimum at the
top to a maximum at the midpoint to a minimum at the bottom, with
no abrupt break therebetween. In this manner, the blades rotate
continuously at a constant speed, without the accelerations and
decelerations which accompany turbines in which the blades pass
discontinuously through the most efficient and least efficient
thrust zones.
50. A resolution of the thrust force exerted on each blade is
illustrated in FIG. 9. The thrust A exerted on each blade 12 is
perpendicular to the leading edge 36 of the blade. The component B,
perpendicular to the rotatable shaft 14, is the working component
of the thrust A, the component which pushes the blade with respect
to the shaft. The component C, parallel to the rotatable shaft 14,
exerts a force parallel to the shaft on the shaft bearings. By
providing two halves with oppositely directed helixes, as shown in
FIG. 5, these components cancel each other out, thereby minimizing
wear on the shaft bearings. The angle .gamma., the angle made by
the leading edge of the blade with respect to the shaft depends on
the particular application.
51. The helical turbine is particularly suitable for hydro
applications where strong water currents develop, and may be
installed on a vessel, as discussed further below, or in the body
of any low-head dam in a river. The helical turbine is also
suitable for harnessing wind and wave energy, as discussed
below.
52. In a further embodiment of the present invention shown in FIGS.
17 and 18, a distributor 206 comprising a generally cylindrical
tubular member is provided in the turbine between the helical
blades 202 and the shaft 214 to extend the length of the turbine
between the turbine supports 208. The distributor 206 is disposed
circumferentially about the shaft 214 and concentric with the
helical blades 202. The distributor 206 redirects the fluid streams
inside the turbine toward the outside rotating blades as indicated
by arrows 210, thereby increasing the fluid flow near the blades
and improving helical turbine efficiency and power output. The
distributor can be fixed to the shaft to rotate with the blades
(discussed further below) or it can remain motionless with respect
to the blades, for example by providing suitable bearings between
the distributor and support discs. If mounted for rotation, the
cylindrical distributor can be mounted to rotate with the same
angular velocity of the blades or a different angular velocity, as
would be known by those skilled in the art.
53. A small scale helical turbine was tested with and without a
distributor both in water and wind tunnels. The turbine was made
from an epoxy-type resin. The test results indicate that turbine
velocities and power output are substantially improved with
inclusion of the fluid distributor. A more than double increase in
efficiency can be achieved in some applications compared with a
turbine without a distributor. Although shown in FIG. 17 with the
helical turbine of the present invention, the cylindrical
distributor can also be used with the Darrieus turbine.
54. As shown in FIGS. 22 and 23, the helical turbine may also be
provided with multiple layers or rings 220, 222 of concentrically
arranged helical blades. FIG. 22 illustrates two rings, each having
three helical blades. FIG. 23 schematically illustrates two rings
each having two helical blades. Although two rings are shown, any
suitable number of rings may be provided. Similarly, any suitable
number of blades per ring may be provided. The spirals of blades of
adjacent rings may be, but are not necessarily shifted with respect
to each other to avoid shielding the inner blades by the outer
blades. The multilayer arrangement provides greater torque and
higher power. The multilayer helical turbine is operable under the
high water heads found in conventional power plants, since the
multiple rings increase resistance to the water flow maintaining
high water pressure.
55. The helical turbine of the present invention is shown in FIG.
10 in operation in association with a hydro-pneumatic power
generation system, such as that disclosed in U.S. Pat. Nos.
5,074,710 or 5,222,833. As generally described above, the system
comprises two water chambers 71, 72 interconnected by ingress and
egress ports 73, 74, 75, 76 on common shafts. As the water level
77, 78 in the two chambers alternately rises and falls, air in the
space above the water level is alternately compressed and expanded.
The air flows through the channel 20 interconnecting the two
chambers, alternating directions in synchronism with the rising and
falling water levels.
56. The turbine 10 of the present invention is mounted within the
channel. The flowing air causes the turbine to rotate as described
above. When the flow of water through the chambers reverses, the
flow of air through the channel also reverses. However, the turbine
continues to rotate in the same direction. During the air flow
cycle, the air flows in a first direction and the speed of the air
increases to a maximum.
57. The turbine is connected in any suitable manner to an electric
generator 79 for generating electricity. The turbine can reach
speeds of 1800 or 3600 rpm with water heads of as low as one or two
feet. Thus, the system is suitable for generating power on rivers
of small grades where high dams are not applicable.
58. The helical turbine of the present invention may be installed
on a vessel 120, as shown in FIGS. 11 through 13. The vessel 120
rises and falls with the fluctuating water level 122, ensuring that
the turbine remains always at the area of greatest velocity. A
catamaran installation is shown in FIGS. 11 through 13, although
any type of vessel or raft may be used. A helical turbine 124
according to the present invention, such as described in reference
to any of the embodiments described herein, is mounted to extend
between two pontoons or hulls 126, 128 of the catamaran and
oriented perpendicularly to the current flow, illustrated by arrows
130. The turbine 124 is mounted below the water's surface 122, so
that all of the turbine is submerged. Water flowing past the
turbine blades 132 causes the blades 132 and shaft 134 to rotate,
as discussed above.
59. Generally, the turbine is mounted either in a housing 136
having a turbine chamber such as described above or without a
housing. The housing, if employed, may have front and back openings
138 therein to allow the current flow 130 to pass through the
housing 136 and past the turbine blades 132. The housing may be
mounted to the pontoons 126, 128 in any suitable manner. However,
in some applications, such as if the current velocity is
sufficiently great, the housing may not need to be provided. The
shaft 134 may be connected to an electric generator 140 in any
suitable manner, such as by a belted transmission 142. As shown,
the electric generator may be housed in a suitable water tight
chamber 144 on the vessel if desired.
60. In a further embodiment, the helical turbine can be efficiently
configured as an optimal unit or module and combined in a modular
array to harness water or wind power. The power available from a
prior art propeller turbine is proportional to the circumferential
velocity of the blades, which increases with distance from the
turbine shaft. Thus, prior art turbines are traditionally designed
with a maximum diameter. However, the size of such prior art
turbines is limited by their strength and possibility of structural
failures caused by centrifugal forces and vibrations when the
diameter becomes too large. The helical turbine is advantageous in
this regard, since its available power is proportional to a frontal
rectangular area equal to the product of its diameter and its
length, and the length is not related to angular velocity or
centrifugal forces. A relatively small helical turbine module can
be optimized for airfoil profile, angular velocity, diameter, and
length, and an entire power system can be assembled from such
modules. Such a power system can exploit a common shaft and
generator for a number of modules and is simple to build and
maintain.
61. A suitable helical turbine module 304 is shown in FIG. 14. The
module comprises one or more helical blades 302 arranged in a
spiral about a central shaft 314. Generally, at least two helical
blades are used. The blades are attached to a turbine support, such
as one or more discs 308 or radial spokes, which is connected to
the central shaft 314, as discussed above. Preferably, the blades
are made from a material which is strong and lightweight, such as
aluminum or fiberglass, and may be hollow if desired.
62. FIG. 15 illustrates a turbine module 304 such as in FIG. 14
combined in an array for harnessing wind power, in which the fluid
flow can be multidirectional. The modules are stacked vertically
end to end. Preferably, the modules are arranged with the direction
of the spirals alternating, such that one module is left handed and
an adjacent module is right handed. A plurality of vertically
stacked modules are arrayed adjacent to each other to provide a
wall 312 of turbine modules. Each vertical stack may be supported
in any suitable manner. For example, structural members may be
arranged to form a lightweight rectangular frame or truss 216, such
as an antenna-type structure, around the vertical stack and
anchored to the ground by guy wires 318. Any desired number of
modules may be provided in any desired number of vertical stacks.
One or more electrical generators 320 are provided in communication
with the vertical shafts. A generator may be individually
associated with each shaft, or plural shafts may be connected via a
suitable transmission to a single generator, as shown in FIG. 21.
The array of modular turbines may be located in any suitable windy
location, as is known in the art, for example for locating
traditional windmill-type wind farms.
63. A further modular embodiment is shown in FIG. 16, in which
turbine modules 304 such as in FIG. 14 are arranged in a horizontal
configuration. A plurality of horizontally disposed shafts 322 are
arrayed vertically in a plane and supported at their ends by
suitable truss members arranged to form a lightweight frame 324.
The frames are anchored to the ground with guy wires 326. A
plurality of generators are supported by the frames in
communication with the shafts. Any desired number of modules may be
provided in any desired number of rows. The rows may be of any
desired length, and any suitable number of frames may be provided
to support the desired length.
64. The array of modular helical turbines is advantageous since it
exploits 100% of the rectangular swept cross-sectional area of the
blowing wind as well as being self-starting. Traditional
propeller-type wind turbines in contrast, must be rotated to face
the wind direction and sweep a circular cross-sectional area. The
helical turbines provide a uniform non-oscillating rotation, as
compared to the prior art Darrieus turbines. The turbines provide
unidirectional rotation for any wind direction except parallel or
nearly parallel to the shaft, for which case no or very little
power can be developed. Also, birds are likely to perceive the
array of rotating helical turbines as a solid wall, minimizing the
danger of collisions, or the turbine modules can be screened to
prevent collisions with birds. The modular system and lightweight
frames provide for structural strength and simplicity in assembly
and maintenance.
65. The modular helical turbines are useful in other applications,
such as in tidal straight or reversible water currents with no dam
construction, or in ultra low-head (less then ten feet) hydropower
plants, in, for example, rivers, canals, or tidal estuaries. The
modules can be used for small power sources in ocean currents to
supply lights or other ocean electrical apparatus. In conventional
power plants, the modular helical turbine can be combined in long
chains or arrays, which is not possible with conventional propeller
type turbines.
66. The helical turbine of the present invention is also useful to
provide propulsion or supplement engine-driven propulsion of a
marine vessel utilizing the power of ocean waves. The helical
turbine is operable under the multidirectional oscillations of
ocean waves. Thus, the helical turbine can develop an axial torque
useful in the propulsion of marine vessels.
67. As shown in FIGS. 19 and 20, a helical turbine 400 as described
above is mounted along each side 402, 404 of a ship 406 below the
water line 408. A propeller 410 is mounted in any suitable manner
to the end of each turbine's shaft. Although two turbines are
shown, any number, including one, could be used. The turbines
provide unidirectional rotation independent of the directions of
the waves oscillations. The turbines are aligned along the ship 406
to provide a forward direction of motion. The longer the turbine's
length, the greater the amount of wave power that can be harnessed.
The length of the turbines are limited only by the length of the
ship.
68. The helical turbines 400 are beneficial as a propulsion source
or supplement, since they are not polluting, are quiet, and
conserve fuel required by the ship's engines. Also, the turbines
stabilize the ship's rocking by utilizing the wave energy.
69. The helical turbine in a vertical orientation may also be used
as a wind sail for a ship. As shown in FIG. 26, a suitable number
of helical turbine modules 601 are attached to the deck of a vessel
602 by a lightweight frame 603 anchored by guy wires 604. In this
case, a suitable transmission 605 for interconnection to a
horizontal shaft and propeller 606 are provided.
70. Lifting or lowering of an object in water can also be
accomplished with the helical turbine in combination with the
cylindrical distributor mounted for rotation with the turbine
shaft. The rotating cylinder develops a lifting or lowering force
depending on the direction of rotation. For example, if the
cylinder is rotating such that its upper surface is moving in the
direction of the current flow, the relative velocity of the upper
surface with respect to the current flow increases and the pressure
thereon decreases, while the relative velocity of the lower surface
decreases and the pressure thereon increases. Thus, a lift force is
developed on the cylinder. Similarly, if the cylinder rotates in
the opposite direction in the same direction of current flow, a
lowering force is developed on the cylinder.
71. Accordingly, relative to a flowing current of water, the
rotating cylinder, driven by the helical turbine, can be used to
raise or lower an object in water. No additional motor is needed to
rotate the cylinder. For example, as shown in FIGS. 24 and 25, a
tug boat 501 dragging a plurality of helical turbines 502 and
cylinders 503 attached to the sides of a submerged object such as a
cargo barge 504 can be used to maintain floatation of or tow the
submersible barge without an engine to drive the turbines. The
barges can be relatively long and large to hold large amounts of
cargo and can be larger than the tug boat.
72. The invention is not to be limited by what has been
particularly shown and described, except as indicated by the
appended claims.
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