Note: Descriptions are shown in the official language in which they were submitted.
-~094l24435 2 16 0 2 ~ 3 PCT~S94/03487
80LAR VENTURI T~RBINE
RELATED APPLICATIONS
This application is a continuation-in-part of
application Serial No. 08/048,481 filed April 16, 1993,
now U.S. Pat. No. 5,300,817 issued April 5, 1994.
FIELD OF THE INVENTION
This invention relates to an apparatus for
generating electrical energy. More particularly, the
present invention is directed to a solar energy
harnessing device which is particularly adapted for use
in combination with a generator to supply electricity.
BACKGROUND OF THE INVENTION
As a result of the increasing costs and
decreasing availability of conventional fossil fuels,
there is an expanding need for an alternative to the
combustion of fossil fuels for the generation of useful
power. Options include atomic and hydroelectric
installations. However, both atomic and hydroelectric
installations have proven to be lacking as commercially
viable alternatives to the production of electricity.
Furthermore, such installations are practically limited
2160~5~
W094/24435 PCT~S94/03487 -
by their potential detrimental affects upon the
environment.
A number of approaches have been developed for
utilizing the sun's radiation to produce useful energy.
Solar energy can provide mer~nical power to generate
electricity without polluting the air and water, or
draining valuable and limited fossil fuel reserves. One
method of using solar energy to produce electricity
involves the creation of an upward flow of air in a
confined conduit. The upward flow of air rotates a
turbine to provide torque capable of driving an
electrical generator.
The upward flow of air in such systems is
generated by allowing the sun's radiation to heat a
volume of air in a substantially confined system. The
heated air convectively rises relative to the colder
ambient air resulting from the heating process. These
thermally induced updrafts or air currents are then
harnessed by a wind turbine. The turbine is geared to
and drives a generator for the production of electricity.
However, in known solar energy systems utilizing the
thermally induced updrafts of air the practical
applicability of such systems has proven to be very
limited. Principally this is due to the specific
structures and features utilized in many of the prior art
systems which are not well adapted or designed for
efficient, reliable, and economical power generation.
Therefore, a need exists for a new improved
W094/24435 21 6 0 2 ~3 PCT~S94/03~7
solar energy apparatus for the production of electricity
which is both pollution free and cost effective.
SU~IARY OF THE INVENTION
It has been an objective of the present
invention to provide a pollution and emission free source
of cost effective power for the generation of
electricity.
It has been a further objective to provide a
solar energy power plant which is operable in a wide
variety of climates throughout the world and can be
adapted to existing electrical power supply circuits and
does not require a significant amount of maintenance.
Still another objective of the present
invention is to provide a solar energy powered
electricity generated plant which can function as a stand
alone unit and can be sized to accommodate a wide range
of electrical power requirements.
These objectives of the invention are obtained
by a solar venturi turbine electrical power plant. The
solar venturi turbine includes an upwardly oriented
venturi tube which has a large bottom neck opening and a
small upper neck opening. The venturi tube is supported
on the ground by a skirt which allows ambient air to be
drawn inwardly to the venturi tube bottom opening.
The venturi tube of the present invention has a
sloped thermopane glass panel which joins the upper neck
of the venturi tube to the lower neck. The present
invention includes a centrifugal fan having a plurality
W094/24435 2 1 6 0 2 5 3
PCT~S94/03487
of vanes. The centrifugal fan is tapered to have a small
diameter at a top end corresponding to the upper neck of
the venturi tube and a larger diameter at a bottom end
corresponding to the lower neck of the venturi tube. The
centrifugal fan fronts to the thermopane glass panels of
the venturi tube and defines a volume of air
therebetween. The centrifugal fan includes a thermally
absorbent coating which aids in heating the volume of air
trapped between the thermopane glass panels and the
centrifugal fan by the irradiating sunlight.
Positioned above the centrifugal fan in the
upper neck of the venturi tube is a high velocity fan. A
high pressure compressor is mounted above the high
velocity fan, and finally a turbine is mounted above the
high pressure compressor. An outwardly tapered venturi
outlet is connected to the upper neck of the venturi tube
above the turbine. The turbine is geared to a shaft
which drives an electrical generator positioned at the
base of the venturi tube below its lower neck portion in
the present invention.
In operation, the sun's rays heat the volume of
air within the thermoplane glass enclosure fronted by the
centrifugal fan vanes. The heated volume of air rises
upward toward the upper neck portion of the venturi tube
thereby creating an updraft of air. The updraft of air
propels the rotation of the centrifugal fan. The heated
air between the thermopane glass panels and the
centrifugal fan is replaced by ambient air which is drawn
W094/~35 6 0 2 ~ 3 PCT~S94/03~7
in through the support skirt of the solar venturi turbine
and cooler and more dense than the heated air it
replaces.
As the updraft of air current is f~,-ced through
the narrowing venturi tube it increases in velocity. The
rising current of air is forced upwardly by the blades of
the high velocity fan positioned within the narrow neck
of the venturi tube. The velocity of air current
continues to increase after passing through the high
velocity fan and is channeled into the high pressure
compressor by a series of guide vanes positioned within
the upper neck of the venturi tube. The high pressure
compressor further increases the velocity of the flow of
hot air and forces the air to turn the turbine positioned
immediately above the high pressure compressor. The
rising updraft of high velocity air turns the turbine
which is geared to a shaft extending back down through
the venturi tube to an electrical generator on the ground
within the skirt support of the present invention.
The solar venturi turbine of the present
invention efficiently produces electrical power by
transforming solar energy into the rotational energy
required to drive the armature of the generator in an
environmentally safe manner. Additionally, the initial
start-up of the solar venturi turbine of the present
invention can be accomplished by providing an electrical
start-up motor which is geared to the centrifugal fan,
the high velocity fan, and the high pressure compressor.
W094/~35 216 0 2 5 3 -6- PCT~S94/03487
The electrical motor acts as an auxiliary means for
providing the initial start-up energy required for the
centrifugal fan, the high velocity fan and the high
pressure compressor. In addition, to maintain the
rotational dynamics required for the generation of
electricity after initial start up, a fly wheel may be
mounted on the backside of the centrifugal fan according
to the present invention. The fly wheel serves to store
the rotational kinetic energy generated by the updraft of
hot air propelling the centrifugal fan and maintain its
rotation through periods of low sunlight activity.
In an improved efficiency version of the solar
venturi turbine of the present invention, the vanes or
blades of the centrifugal fan are configured so as to
spiral radially outwardly in a clockwise direction when
viewing the fan and top plan.
BRIEF DESCRIPTION OF THE DRAWINGS
The objectives and features of the present
invention will become more readily apparent from the
following detailed description taken in conjunction with
the accompanying drawings in which:
Fig. 1 is a side elevational view of the solar
venturi turbine of the present invention;
Fig. 2 is an enlarged cross-sectional view of
the solar venturi turbine taken along line 2-2 of Fig. 1;
Fig. 3 is a top elevational view of a
centrifugal fan of the present invention;
Fig. 3A is a side elevational view of the
NO94l~435 21 602S3 ~ PCT~S94/03487
centrifugal fan of Fig. 3;
Fig. 4 is a cross-sectional view of a high
velocity fan of the present invention taken along line 4-
4 of Fig. 2;
Fig. 4A is a partial side elevational view
between line 4a-4a of the high velocity fan of Fig. 4;
Fig. 5 is a cross-sectional view of a plurality
of guide vanes of the present invention taken along line
5-5 of Fig. 2;
Fig. 5A is a partial side elevational view
taken between line 5a-5a of the guide vanes of Fig. 5;
Fig. 6 is a cross-sectional view of a high
pressure compressor of the present invention taken along
line 6-6 of Fig. 2;
Fig. 6A is a partial side elevational view
taken along line 6a-6a of the high pressure compressor of
Fig. 6;
Fig. 7 is a cross-sectionial view of a turbine
of the present invention taken along line 7-7 of Fig. 2;
Fig. 7A is a partial side elevational view
taken along line 7a-7a of the turbine of Fig. 7;
Fig. 8 is a view similar to Fig. 3 of a
centrifugal fan of improved efficiency of the present
invention; and
Fig. 8A is a view similar to Fig. 3A of the
centrifugal fan of Fig. 8.
DETAILED DESCRIPTION OF THE INVENTION
Referring to Fig. 1, a solar venturi turbine 10
W094t24435 21 6 0 2 5 3 -8- PCT~S94/03487
according to the present invention is shown. The solar
venturi turbine 10 is positioned on the ground 12 or
other suitable surface and supported by a skirt 14 having
openings 16 through which ambient air may be drawn into
the solar venturi turbine 10. Supported atop the skirt
support 14 is a venturi tube 18 having at its lower end a
large diameter neck 20 and at its upper end a narrow
diameter neck 22. A number of thermopane glass panels 24
are provided on a tapered region of the venturi tube 18.
In the preferred embodiment of the present invention, the
thermopane glass panels 24 are tapered on approximately a
angle between the upper neck 22 and the lower neck 20
of the venturi tube. Immediately behind and fronting the
thermopane glass panels 24 of the present invention is a
tapered centrifugal fan 26 having a plurality of fan
vanes 28. The centrifugal fan 26 is likewise tapered at
an approximate 45 angle having a narrow diameter upper
region 30 and a larger diameter lower region 32.
Extending upwardly from the narrow upper neck
22 of the venturi tube 18 is an outwardly flared venturi
outlet 34. The venturi outlet 34 has an uppermost
opening 36 which allows the air exiting the solar venturi
turbine 10 of the present invention to return to the
atmosphere.
2S Fig. 2 shows the internal components of the
solar venturi turbine 10 of the present invention
including the tapered centrifugal fan 26 with the fan
vanes 28 which front the thermopane glass panels 24. The
W094/24435 21 ' ~ PCT~S94/03~7
fan vanes 28 and centrifugal fan 26 have a thermally
absorbent black coating or layer 38 which enhances the
heating of a volume of air 40 between the thermopane
glass panels 24 and the cencrifugal fan 26. To further
increase the thermal effect of sunlight 39 which impinges
upon the centrifugal fan 26 through the thermopane glass
panels 24, a layer of insulation 42 is provided on a
backside 44 of the centrifugal fan 26.
Also attached to the back 44 of the centrifugal
lo fan 26 is a rotational fly wheel 46 used for storing
rotational kinetic energy generated by the centrifugal
fan 26. The fly wheel 46 and centrifugal fan 26 are
mounted on a central drive shaft 48 extending generally
vertically within the solar venturi turbine 10 of the
present invention. The centrifugal fan 26 and the fly
wheel 46 rotate on the axis of the drive shaft 48 during
normal operation.
To assist in the start-up of the solar venturi
turbine 10 and initiate the rotation of the centrifugal
fan 26, a motor 50 is provided within the venturi tube 18
of the present invention and meshed with the drive shaft
48 through a gear box 52. In the preferred embodiment of
the present invention, the rotation of the centrifugal
fan 26 and the fly wheel 46 is counterclockwise.
Positioned above the centrifugal fan 26 and in
the narrow neck of the venturi tube 18 is a high velocity
fan 54. The high velocity fan 54 increases the velocity
of the upwardly moving volume of air 40 and is also
2l6o253
W094/24435 PCT~S94/03487
--10--
geared to the drive shaft 48 via gear box 64 to benefit
from the start-up motor 50 upon the initial operation of
the solar venturi turbine 10. As the volume of air 40
vents upwardly through the venturi tube 18 it is directed
by a plurality of guide vanes 56 positioned just above
the high velocity fan 54 in the upper neck 22. The guide
vanes 56 serve to direct and focus the upwardly moving
current of air 40 into a high pressure compressor 58 also
located in the upper neck 22 of the venturi tube 18. The
high pressure compressor 58 is also geared to the drive
shaft 48 via gear box 64 to benefit from the start-up
motor 50 for initial operation.
Positioned immediately above the high pressure
compressor 58 in the narrow neck 22 of the venturi tube
18 is a turbine 60. In response to the updraft volume of
air 40 generated in the upper neck 22 of the venturi tube
18, the turbine 60 rotates and is geared to a turbine
shaft 62 connecting the turbine 60 to an electrical
generator 66 via gear box 52 positioned below the turbine
60 within the support skirt 14 in the preferred
embodiment of the present invention.
The outwardly flared upwardly directed venturi
outlet 34 is attached to the narrow neck 22 of the
venturi tube 18 adjacent the turbine 60. As the air is
drawn into the solar venturi turbine 10 through the
support skirt 14 and large diameter lower neck 20 of the
venturi tube 18 it increases in velocity upon passing
through the venturi tube narrow upper neck 22 to exit
~094/~435 2 1 6 0 2 S ~ 11- PCT~S94/03487
through the large outwardly flared venturi outlet 34.
In the operation of the solar venturi turbine
10 of the present invention, the initial start-up is
accomplished by the motor 50 which is geared to the
centrifugal fan 26 via gear box 52, and to high velocity
fan 54 and the high pressure compressor 58 by the drive
shaft 48 and gear box 64. Once the motor 50 initiates
the counterclockwise rotation of the centrifugal fan 26,
the high velocity fan 54, and high pressure compressor
58, the solar venturi turbine 10 of the present invention
is designed to generate electrical power in a self-
sustaining fashion. Sunlight 39 projects through the
thermopane glass panels 24 on the taper of the venturi
tube 18 and upon the thermal absorbent coating 38 of the
centrifugal fan 26 fronting the thermopane glass panels
24 in the preferred embodiment of the present invention.
Air trapped between the panels 24 and coating 38 is
heated, thereby causing the air to rise further driving
centrifugal fan 26.
The centrifugal fan 26 is as shown in Figs. 3
and 3A with the plurality of generally J-shaped fan vanes
28 which are oriented radially outward from a center 68
of the fan. A longer leg 70 of each J-shaped fan vane 28
is attached to a centrifugal fan housing 72. A hook
portion 74 of each fan vane 28 is downwardly oriented
toward and spaced from the surface of the centrifugal fan
housing 72. Each fan vane 28 is designed such that the
hook portion 74 is more narrow toward the center upper
2~602s3
W094/24435 -12- PCT~S94/03487
region 68 of the centrifugal fan relative to a perimeter
lower region 32 of the centrifugal fan 26. This design
assists in the rotation of the centrifugal fan 26 in that
the upwardly moving air 40 flows within each fan vane
hook portion 74 and the geometry of each fan vane 28
thereby assists in the counterclockwise rotation of the
centrifugal fan 26. The area within each fan vane 28
decreases upwardly thereby increasing the rotational
energy delivered by the updraft of air 40 in the upper
region 68 of the centrifugal fan 26.
As the air 40 is heated and is advanced
upwardly through the tapered centrifugal fan 26, it
enters the narrow neck 22 of the venturi tube 18 and
encounters the high velocity fan 54 shown in Figs. 4 and
4A. Like the centrifugal fan 26, the high velocity fan
54 rotates counterclockwise in the preferred embodiment
of the present invention and increases the velocity of
the updrafted air 40 passing through. The high velocity
fan 54 has a plurality of radially extending fan blades
78 which have a scalloped shaped profile and are mounted
on a housing 80. The rotation of the scalloped shaped
fan blades 78 serves to further increase the velocity of
the updraft of air 40 passing through the narrow neck 22
of the venturi tube 18.
The updraft of air 40 exiting the high velocity
fan 54 of the present invention encounters the radially
extending guide vanes 56 shown in Figs. 5 and 5A. These
non-rotating guide vanes are secured on the gear box 64
~094/24435 ~ PCT~S94/03487
and serve to direct and focus the upwardly moving air 40.
The guide vanes 56 channel the air 40 into the high
pressure compressor 58 located immediately thereabove and
shown in Figs. 6 and 6A. The high pressure compressor 58
5 has a plurality of radially extending compressor tines 84
which are arranged in a plurality of layers 86 as shown
in Fig. 6A. The high pressure compressor 58 further
increases the velocity of the flow of warm air 40 passing
therethrough.
Figs. 3-6 show the drive shaft 48 connecting
the centrifugal fan 26, the high velocity fan 54, and the
high pressure compressor 58. The drive shaft 48 is
meshed to the gear box 52 adjacent the start-up motor 50
as shown in Fig. 2. The fly wheel 46 which backs the
15 centrifugal fan 26 is also geared to the drive shaft 48
to provide rotational kinetic energy to the solar venturi
turbine 10 once rotation of the drive shaft 48 and
centrifugal fan 26 is established.
The updraft of air 40 exiting the high pressure
20 compressor 58 passes through and turns the turbine 60
located in the upper neck 22 of the venturi tube 18 and
shown in Figs. 7 and 7A . Once the upwardly moving air 40
exits the turbine 60 it is directed around a turbine cone
88 mounted upon a turbine housing 90 and into the
25 outwardly flared venturi outlet 34 and is returned to the
atmosphere.
The turbine 60 which rotates in response to the
updraft of air 40 drives the turbine shaft 62 concentric
W094/24435 ~6 o~3 PCT~S94/03487
-14-
with the drive shaft 48. The turbine shaft 62 is meshed
with the gear box 52. The turbine shaft 62 drives the
electrical generator 66 at the desired RPM to produce a
60 cycle current output from the electrical gener~or 60.
Once the solar venturi turbine 10 is to be shut down, at
sunset for example, the generator 66 can be taken off
line and the solar venturi turbine 10 will gradually shut
itself down.
The solar venturi turbine 10 of the present
invention provides an efficient and environmentally harm-
free production of electricity by converting the thermal
energy of the sun's rays into electricity. Furthermore,
once operational the solar venturi turbine 10 will
require a minimal amount of maintenance and does not
require the use of fossil fuels or other diminishing
energy supplies. The solar venturi turbine 10 can
function in a stand-alone capacity in any desired climate
without being enclosed in a building or infrastructure.
Additionally, the spatial dimensions of the solar venturi
turbine 10 can be adjusted and sized to accommodate a
wide range of kilowatt requirements. Alternatively, the
solar venturi turbine 10 as a source of energy can be
coupled with machines other than the electrical generator
66 such as a line shaft, a mill, or other power requiring
apparatus depending upon the specific application.
An improved efficiency centrifugal fan 26 is
shown in FIGS. 8 and 8A. With like numbers representing
like elements, a plurality of generally L-shaped fan
~094/24435 21 6 0 2 ~ 3 PCT~S94/03487
vanes 100 are oriented radially outward from the center
68 of the fan. A leg portion 102 of each L-shaped fan
vane 100 is attached to the centrifugal fan housing 72.
A foot portion 104 of each L-~Aaped fan vane 100 is
spaced from the surface of the centrifugal fan housing
72. Each fan vane 100 is designed such that the foot
portion 104 is more narrow toward the center upper region
68 of the centrifugal fan relative to a perimeter lower
region 32 of the centrifugal fan 26. Additionally, as
seen in FIG. 8, the vanes 100 are configured on the fan
housing 72 so as to spiral radially outwardly in a
clockwise direction, as viewed in top plan in FIG. 8.
This embodiment of centrifugal fan 26 is more efficient
and results in a more efficient overall solar venturi
turbine 10.
From the above disclosure of the general
principles of the present invention and the preceding
detailed description of the preferred embodiment, those
skilled in the art will readily comprehend the various
modifications to which the present invention is
susceptible. Therefore, I desire to be limited only by
the scope of the following claims.
I claim: