FR2525694A1 - Flow energy conversion using water wheels and guide walls - uses guides to converge fluid flow and has hemi-cylindrical cut=outs in wall to shield returning side of wheel - Google Patents

Abstract

The flow energy of rivers and streams is converted to rotational mechanical energy using a diverting wall built across part of the width of the stream, forcing the flow to converge into the water wheel enclosures which are hemi-cylindrical cut-outs in a wall, covering half the wheel from the flow but leaving the other half exposed to the flow. The water wheel has fixed radial arms carrying pivoted blades (8,9). The side of the wheel shielded by the hemi-cylindrical cut-out has the blades in the closed position perpendicular to the radial arm for minimum drag as they move through the water. A fixed gear segment is used to open the blades progressively out to the radial position when the blade is in the main flow, and to withdraw it again as the blade approaches the shielded region.

Description

 The present invention relates to a method of arrangement of a fluvial energy power station over the water, using the increase in the speed of the water current resulting from an artificial constriction of a part of a wet section of river caused by a current diverting structure.

The current technique of generating motive force from rivers, in almost all cases, calls for a fall obtained by a dam transversely cutting the watercourse0
In addition to the drawbacks of a dam, the auspicious sites are practically exhausted to this day, and the extent of energy production by this means is paralyzed.

 The process proposed in the present invention makes it possible to recover a large amount of the energy carried in the water stream and currently lost. It also brings the great advantage of accommodating a multitude of Sites available along the rivers.

 The description below is explained by the accompanying drawings giving examples, which are non-limiting, making it possible to achieve practical realization.

Fig. 1 shows the tightening of a part of the wet section using a deflection structure () of the simplified pier type.
withholding, intercepting a certain width of water upstream. The positioning will preferably be on the inside of a curve so that in flood conditions, the main current and the objects carried in this situation pass offshore over the deflector. The latter can constitute a riprap or other cons
usual truction in the material slightly emerging from water, on
its upstream side, Up to the level corresponding to the start of the
raw in which case the diverter must be crossed normally A
shallow water depth, more or less marked ford, is profitable
for the initial water speed, the installation
and evacuation downstream.

The tightening ends in a construction, in the form of
two quays (2) defining a channel to allow passage to a
intense and fast current. A speed of at least 4 to 5 meters
second or more, being desirable, the depth being several
meters. The lateral edges of the channel are vertical and parallel
or slightly converging downstream. They have at least one,
or several recesses (3) made in the construction, including
the section is semi-cylindrical, the vertical axis and the diameter in alignment with the corresponding lateral edge according to the principle of FIG. 2. Rockfill (4) reinforces the bank upstream and downstream of the corresponding quay. A set of grids (5) and possibly valves, can be provided at the entrance to the channel.

 Depending on the flow rate of the watercourse, various types of arrangements are possible according to the examples in FIGS. 3-4-5 .The width of a channel is substantially equal to the diameter of a recess or twice that diameter in the case of opposite recesses.

 Each recess is equipped with a horizontal hydraulic wheel with blades, of diameter slightly smaller than that of the recess and whose axis is vertical. Half a wheel is thus out of the recess, in the stream, and the other half, in the recess, out of the stream.

 Fig.6 shows, in vertical section along a diameter perpendicular to the currents, a schematic view of such a wheel. Two flanges (6) formed of radial arms with equal angular spacings and their fairing, are integral with the wheel shaft (7). The fairing means that each flange takes the form of a disc meeting little resistance in its rotation in the water. Two rad arms in the same vertical plane, support between them, re-tangular vanes (8) each secured to a clean vertical shaft (9): parallel to that of the wheel and pivoting in the support arms cs wespondants.

 The upper end of each blade shaft receives a rotation control member as indicated below.

 Fig. 7 shows a possibility of maintaining the rsle by means of a frame-shaped chassis (IG3 on which it is articulated by its shaft.

An example of installation in the hollow of the esz platform given
Fig. 8, the chassis being simply slid into two vertical guides (11) formed in the wall of the recess.
rack or similar, may be provided between the guide and the chassis to facilitate checks or maintenance of the assembly. The wheel is completely submerged and subject to the influences of two different sectors: One says ACIP, in the current (12), the other PASSIVE (I3), out of the current.

The operation of the wheel is schematically explained in FIG. 9. Each group of blades on the same radial arm (9) receives an orientation command such as an optimal force
water, on the wheel shaft, is obtained in the sector
ACTIVE against minimum resistance in the PASSIVE sector. The engine torque of the wheel is the difference of these forces.

Thus from entry into ACTIVE sector until exit from it, each blade rotates relative to the radial direction of its arm, so that its plane is maintained in optimal orientation with respect to the direction of the current, according to l example of Fig. 9
On the other hand, throughout the PASSIVE sector the plane of each blade is kept fixed relative to the radial direction of its corresponding arm and remains substantially tangent to the circulation circle of the blade shaft around the wheel. Note that in the PASSIVE sector, the successive blades are in the wake of each other, the assembly forming the side wall of a regular polygon approaching all the more a cylinder as the widths d 'dawn are reduced.This reduces the passive forces due to the rotation of the wheel in the water of this sector, unless there is a circular current maintained in the same direction by the main current.

 The case of Fig 9 assumes a wheel with twelve radial arms and two crowns of blades. 0n could, of course, retain other combinations on this same principle, but it seems that a fork of 8 to twelve arms is suitable. Below, efficiency is felt and complexity becomes annoying above.

 Adequate profiling of the upstream quay-recess junction (14) promotes the attack of the blades at the start of the ACTIVE sector, that downstream (15) deflects a current helping the maintenance of the circular current, favorable to the rotation of the wheel, and resulting from the drive between the current of the channel on that in passive sector.

Fig. 10 offers a possible means of orientation
vanes. It uses bevel gear (I6) half action
born by a pinion (I?) meshing itself on a crown
toothed (I8) remaining fixed. A crank pin (20) provided with a roller (211, and
a guide (22) complete the order. The set I6-I7-20-21 and
their connection, is integral with the wheel and turns with it, while
that the half-crown and the guide are integral with the general frame
(I9). According to fig. 11-at the pinion drive (I7) does not take place
that on the half crown, laque11e, corresponds to the path of the blades
considered in the ACTIVE sector. Then in the whole sector
PASSIVE, Fig. 11-b-the roller (2I) circulates in the guide (22) and maintains the blade control crankpin in a fixed angular position relative to the corresponding radial arm.

As many pinions (I7) as there are radial arms carrying blades are necessary and their arrangement, FIG. I2, constitutes the HEAD OF
ORDERED. Due to the angular size, two gears consecutively offset in height according to two different levels to which correspond two half-crowns (in), on the other hand> all the crankpins are at the same level during the guide, only the rollers borrowing this.

 An adequate drive ratio of the pinion (I7) means that the roller (21) is present at the entrance to the guide according to the example in the figure. With ratios close to the unit being retained, the speed of rotation of the members control is very low, dispensing with lubrication of the submerged parts. The control effort is also low, because the vanes selcomportent according to the principle of a butterfly valve.

 Note that the wheel does not include speed regulation, which can never become prohibitive. A global regulation is practiced at the level of energy use as indicated below.

 The difference in driving forces and resistances, or engine torque is reported on the wheel shaft. This torque can be relatively large depending on the surface of the blades, the radius of the wheel and the speed of the current flowing in the channel, the values of which are provided at several meters or square meters.

Except in special cases of error, the speed of rotation of the wheel will generally be insufficient for direct use from the shaft. A usual mechanical multiplication is possible but the reduction in torque which follows may be detrimental.
gible for high speed applications. It will therefore be preferable
tily uses an energy converter allowing
to obtain, without too many losses, an energy in necessary speed
from that at slow speed provided by the wheel. Among
different possible ways, we can use a compres
fluid, liquid or gaseous sor, operating for example in cir
cooked closed.

Fig. I3 schematically gives a possible example which
uses compression cells placed in a crown and for
boasting of the double effect type. They are operated by a
common eccentric, fixed in the center, on the wheel or idler shaft.

The high pressure fluid is collected by a line (24), a similar line (25), on the other face of the crown, ensuring the supply of pressure
Fig. I4 shows the device in elevation where it appears that several assemblies can be actuated on the same shaft and provide, then, a relatively high flow rate at high pressure for a reasonable size.
Fig 15 in which the compression cells are placed side by side on one or more floors. However, this arrangement seems more penalizing from the point of view of control and size.

 In both cases, the compressor flow varies over time depending on the speed transmitted by the wheel, which is influenced by the flow of the river. Although possible, there is also no provision for regulating the compressor flow, regulation at the level of energy use offering other possibilities while simplifying the wheel and the compressor.

 An example of an energy generator, mechanical or electric, is the subject of FIG. I6 and works in a closed circuit by direct connection to the compressor outputs. The high pressure fluid actuates the turbine (26) of the generator then returns to a low pressure storage tank (27) from which it is again taken up by the compressor. A regulating member (28) acts simultaneously on the inlet (29) of the fluid to the turbine and on a bypass van (30) acting so that the pressure necessary for the turbine remains constant. The capacity of this bypass is greater than the maximum capacity of the compressor and allows complete shutdown of the generator supply for possible shutdown.

This bypass absorbs, first of all, the variations in power of the hydraulic wheel in repercussion of the variations in the flow of the river, but it can also play the following very advantageous role: Depending on the flow rate, an organ measuring this flow can automatically start up and shut down, one or more turbines of equal power or divisional one of
others, supplied together on a common compressor output.

This process makes the most of a wide range of
powers generated on the water wheel from the level
of the low water level Up to the flood level, the wheel continuing
has to operate in the latter situation
From the point of view of general installation, the compressor and generator assembly can be placed in a room placed above the wheel or else be deported nearby, but out of floods in both cases.

 Figs. I7 to I9, also report another possibility of installing hydraulic wheels of the type described above.

In this case, the channel consists of a floating but suitably ballasted barge (37), which can be directly moored in the current of a river. A shield (36), in a large grid, protects large objects circulating on the water, the ballast (31) being able to be river materials. Compressor and generator are then placed in a passenger compartment (32).

 The mooring is the object of FIG. I9 in which a cable (33) is stretched in two branches and clrcuDeNtelle a belt on two pulleys with groove (38) established on bank. The cable is a few meters above the water, the mooring of the barge is fixed at points (34) and slides by rollers (35) on the second branch of the cable. In flood conditions, the whole can be brought, manually or automatically, to the shelter in a calm zone (39) fitted out on the bank.

 The application of the facilities described above, - energy production in general.

Claims (5)

 -. CLAIMS  wet from a river.  tie downstream of an artificial tightening of a section part  several quays (2) defining one or more channels, exiting  located in the vertical walls of a structure forming two or  particular, immersed and housed in recesses (3) practi  horizontal wheels impellers (8), designed by  fil de lteau, characterized in that it uses one or more I) - Method for fitting out a river energy center at 2) - Method of arrangement of power plant according to reven  dication No I, characterized in that the wheel housing (3) is  a vertical, semi-cylindrical volume, of height equal to that  of the channel, the diameter being in alignment with the wall cor  correspondent of the channel. 3) - Method of arrangement of power plant according to reven  dications NO I and 2, characterized in that each wheel is  secured and articulated by its shaft, on a frame chassis (IO)  installation in the housing by sliding the sides  vertical tees of the frame in guides carried by the 'wall of the  housing. In this position of use, half a wheel  occupies the entire width of the channel and is subject to current there  fast, the other half, being sheltered from the current in the lodge  is lying. 4) - Method of arrangement of power plant according to reven  dications NO I and 3, characterized in that the blades receive  an optimal orientation control, such that, as long as they  are in the current, they rotate about themselves by about  2 4/3, opposite to that of the wheel, then their plane  is kept tangent to their circle of rotation around the  wheel, in all their journey sheltered from the current in the box  is lying. 5) - Method of arrangement of power plant according to the set  ble of the above claims, characterized in that wheels  and subsequent equipment, can be installed on a  bargfiarrée in the middle of a river