WO2019220469A1

WO2019220469A1 - Fine rake suitable for being installed in a water catchment

Info

Publication number: WO2019220469A1
Application number: PCT/IT2018/000072
Authority: WO
Inventors: Markus Wild
Original assignee: Wild Metal Srl
Priority date: 2018-05-18
Filing date: 2018-05-18
Publication date: 2019-11-21

Abstract

The invention relates to a fine rake (1), which is suitable for being installed in a water catchment (2), said water catchment (2) being positioned in a watercourse in order to remove water from said watercourse. According to the invention, the fine rake (1) has fine rake bars (7; 8; 9; 10; 11), arranged crosswise to the longitudinal direction (A) of the fine rake (1), which fine rake bars (7; 8; 9; 10; 11) are parallel to each other and arranged densely adjacent to each other, such that each pair of adjacent fine rake bars (7; 8; 9; 10; 11) delimits a respective fine rake slot (12) therebetween. Said respective fine rake slot (12) has an inlet opening (12a), having a width that is smaller than 2mm, wherein water that does not flow into the fine rake slot (12) discharges along the fine rake (1) and thereby determines a flow direction (B). At least the part of each fine rake bar (7; 8; 9; 10; 11) determined for the discharge of the removed water and coming into contact with the removed water has a cornerless cross-section, wherein a first section (7a;8a;9a; 10 a; 11a) of the contour of said cornerless cross-section extends along a direction which also has a component which is parallel to the longitudinal direction (A) of the fine rake (1) and is directed in the flow direction (B) of the discharging water.

Description

FINE RACING THAT IS SUITED TO BE BUILT INTO A WATER CONSTRUCTION

DESCRIPTION

Technical area

The invention relates to a fine rake, which is suitable to be installed in a water intake, according to the preamble of claim 1. For removing water from a watercourse, a water intake is aufgestelit in this watercourse that in the Strömungska channel of the water intake flows a water flow , At least part of this water flow then flows through at least one rake, which is part of the water intake, and then flows into a collection channel, which is also part of the water intake. As a result, water is withdrawn from the water flow, from which the entrained foreign bodies have been discharged, the size of which is greater than the mutual distance between the screen bars. The collecting channel serves to collect the extracted water and to guide it to the intended point of use. Such a point of use is, for example, a power plant for the generation of electrical energy, in which the supplied extracted water is used to bring a turbine in rotation.

Depending on the characteristics of the watercourse in which the water intake is set up, such a water intake can also have two rakes, namely a coarse screen and a fine screen, which are flowed through in sequence. In such a water intake water is removed, from which the entrained foreign bodies were ejected, the size of which is initially greater than the mutual distance between the coarse calculation bars and then subsequently greater than the mutual distance between the fine rule bars.

When choosing the distance between the fine rule bars, two different aspects are in conflict with each other. On the one hand, this should be Distance should be as small as possible, so that even small foreign bodies such as the grains of sand can be eliminated from the removed water and the extracted water can also be fed to points of use in which such small foreign body are undesirable. On the other hand, however, this distance should not be too small, because the smaller this distance, the smaller the flow cross section of the fine bill that is available for the extracted water.

State of the art

Document EP 3 023 165 discloses a fine rake according to the preamble of claim 1.

In this fine rake, the cross-section of each fine rake is triangular, each one of the three flat legs of the fine rake is part of the fine rake surface on which flows the fine rake overflowing water. The fine rake bars can be detachably fastened as part of the fine rake, so that either each of the three fine rake bar legs can be attached to the o.g. Surface can belong and in the order each of the three fine rake edges can be used by protruding in the flowing water to mechanically shear water layers from the flowing water and dissipate into the fine mesh formed between the fine mesh bars. This will increase the life of each fine-mesh bar.

The documents CH 708046 and CH 708203 reveal a fine compute according to the preamble of claim 1.

In this fine rake, the cross section of the fine rake bars is semicircular and the fine rake bars are arranged such that the various flat surface areas of the fine rake bars form the upper surface on which the fine rake overflowing water flows. This surface corresponds to the surface which is formed in the above-explained fine rake by the various flat fine-rule limbs. Also in this case of the two Swiss The fine rake disclosed above projects one edge of each fine rake rod into the water overflowing the fine rake in order to mechanically shear water layers from the flowing water and to discharge them into the fine rake slots formed between the fine rake rakes.

As the drained water flows into a fine-meshed slot, it hits the rounded surface area of a fine-particle screen. As one also from the designation of the o.g. As far as Swiss documents are concerned, this fine-tuning attempt has been made to exploit the so-called Coanda effect, which is so named because of its discoverer, the Romanian aeronautical engineer Henri Coanda.

Henri Coandä noted that a fluid, as well as a liquid such as water, tends to follow the contour of the surface upon which it impinges. This is caused by friction occurring as the liquid slides along the surface, and this friction tends to slow down the internal liquid particles directly in contact with the surface while the remaining liquid particles maintain their velocity such that the latter intervenes due to molecular interactions as a result of the particles and, owing to the difference in speed, roll on the inner particles and consequently cause the adhesion of the liquid to the surface. This adhesion makes it possible to increase the flow of the fine rinsing through water flowing through. The well-known Coanda fine screen, however, makes little use of the Coanda effect for the following two reasons: on the one hand, it causes a fine-meshed edge to pass the extracted water to flow into a fine-meshed slot, which makes the attachment more difficult on the other hand, the semicircular surface on which the extracted water should adhere is directed downward, so that gravity tends to dissolve the water from this surface. Presentation of the invention

The object of the present invention is therefore to further develop such a fine rake of the type specified that the swallowing performance of the fine rake is significantly increased and thereby the flow of the fine rinsing through and thus ent taken water is increased, in particular by a more effective use of Coandä effect, so that a chen the invention Feinre having water intake in comparison to other water tanks, which have the same dimensions but not the fine screen according to the invention, is more effective.

A possible water intake for removing water from a water flow flowing in it, into which a fine screen according to the invention can be installed, is e.g. in the document AT 508727 A1 of the applicant. Such a water intake is distinguished from the other known types of water intake by the fact that the upper end of the coarse crush and the upper end of the fine screen have no appreciable mutual displacement both along the vertical direction and along the flow channel longitudinal direction. The fine rake is located directly under the coarse screen and the collection channel is located directly under the fine screen, so that a total drop height of the extracted water is guaranteed, which can be fully utilized and compared to the total fall height is seen in other known water tanks, is smaller.

The above object is achieved if a fine rake of the type specified in addition also has the features that are specified in the characterizing part of claim 1.

As a result of the cornerless shape according to the invention of the cross section to at least the particular for the discharge of the extracted water and coming into contact with the removed water part each Feinrechenstabes, the fine-mesh surface corresponding to this corner-free cross-section surface is edge-free and that means that each fine rule bar just where the water is discharged is a edgeless bar. This fact helps to combat vortex formation and this is important in order to ensure regular flow conditions, the presence of which is an important prerequisite, since the water flowing into and thus removed from the finer sheathing dissolves as late as possible from the surface of the fin screen and thereby until the last can use the Coanda effect. The further feature provided according to the invention that a first section of the contour of the above-mentioned corner-free cross-section extends along a direction which also has a component lying parallel to the longitudinal direction of the fine rule and directed in the direction of flow of the outflowing water results for the operation of the invention. A fine difference according to the invention in comparison with the operation of the known fine rake.

Namely, the water flowing into and thus discharged from a fine-meshed slot flows on a fine-particle surface which also extends along one of the above-mentioned o-ring surfaces. Component having direction extends. Such a surface is most suitable for the commencement of the Coanda effect, because the fine particle screen can support the extracted water through it and thereby combat the effect of gravity, which is known to tend to separate the extracted water from the fine particle surface. Would it be the o.g. Surface is not, then the water would flow chaotically to Feinrechenschlitzauslauf, as happens in the known fine rake, in which the water is mecha nically derived from the fine rake, i. due to the impact of the water on the fine screen surface.

If the above-mentioned first section is curved, in particular convexly curved, as claimed in claim 2, the first section shown in claim 2 is also curved. the surface of the water cut convexly and the upper layers of the water flow faster than on a straight surface, so more water can be extracted.

If, according to claim 3, the contour of the corner-free cross section has a rounded projection, which is directed in the direction of flow of the water flowing from opposite direction and adjoins the first section, a regular partial flow of the flowing Drained water and fed to the fine screen slot, thereby increasing the amount of water removed.

It may additionally be provided that, according to claim 4, also a second portion of the contour of the corner-free cross-section extends along a direction which also has a component lying parallel to the longitudinal direction of the fine and directed in the flow direction of the outflowing water. Also, this second section, like the first section, joins the rounded projection, but the surface corresponding to this second section is not on the same side of the fine screen on which the surface corresponding to the first section is located other side of the fine atomizer. This second section is to be credited ken, that the respective distance between the two walls of the fine rake slot always has a sufficient size, so as to avoid possible that the flowing on one wall of the fine-rule slot according to the Coandä principle water against the other wall of the fine-prone slot, thereby jeopardizing the Coanda effect.

If, as described in claim 5, the second section is concavely curved, then even more the danger is reduced that the water flowing on one wall of the fine-particle slot according to the Coandä principle impinges against the other wall of the fine-particle slot. According to claim 6, each fine-calculation slot on an outlet opening, the width is greater than the width of the inlet opening. As a result, the fine-gauge slot widens in the direction of the outlet opening, whereby this enlargement also contributes to maintaining the Coanda effect as long as possible. Namely, it can not be excluded who the that when flowing through the fine-mesh slot through water droplets dissolve from the flowing according to the Coanda principle water. These drops of water become more and more the more you approach the outlet opening. Enlargement provides the necessary space to allow these drops of water to continue chaotically without jeopardizing the Coandä effect and, on the other hand, any small foreign objects still remaining in the water will not be trapped between the fine-grained slot walls or, if so, easier to recover get free.

It would be optimal if, according to claim 7, the contour of the entire cross section of each fine-scale rake would be corner-free, because the resulting edges of the surface are detrimental Lich for the Coanda effect. The rounding off of all possible corners or edges is not always possible both for cost reasons and for production reasons. In these cases, it is sufficient, according to claim 1, at least for the derivation of the extracted water and with the ent taken water coming into contact part of each fine-grade rake cornerless or edge-free manufacture.

According to claim 8, in order to make the water flowing on the fine screen surface flow faster, it is possible to provide that a third section of the contour of the corner-free section of each fine screen is convexly curved and extends along a direction which is also parallel to the longitudinal direction Having the fine rule and directed in the direction of flow of the outflowing water directed direction directed component. This third section follows to the first section. The fact that the component is directed in the opposite direction to the flow direction of the outflowing water, one reaches on both sides of an increasing expansion of the fine-calculation slot. This circumstance also makes it easier to expel any foreign bodies still in the water from the fine-meshed slot

According to the further claims, at least a portion of the Feinre Chen is concave. In addition, at least a portion of the fine rule may be convex. With regard to the width of the inlet opening of each fine particle slit, this width is a value which lies between 0.4 mm and 2 mm. It can be in particular 0.6 mm.

Brief description of the drawings

In the drawings show:

FIG. 1 is a perspective view of an exemplary water socket incorporating the fine screen of the present invention, the left shoulder of the foundation and support structure of the water socket not shown in FIG. 1 to show the interior of the water socket; FIG.

Figure 2 is a perspective view of a longitudinal section of the fine rule according to the invention of Figure 1, alone and in the case of a ers th embodiment of the fine rule bars ..;

FIG. 3 shows a front view of the fine rake according to the invention in the case of a first exemplary embodiment of the support means supporting the fine rake bars;

Figure 4 is a side detail view of the longitudinal portion of the Feinre Chen of Figure 2;

FIGS. 5-8 show a side view, similar to FIG. 4, of a longitudinal section of the fine rake according to the invention in the case of four further exemplary embodiments of the fine rake bars;

FIGS. 9 and 10 show a front view similar to FIG. in accordance fine fine each case in the case of a second or third example Ausfüh tion of the fine rule bars supporting support means.

Best way to carry out the invention

Further advantages and features of the invention will become apparent from the following description of at least one embodiment of the fine refining according to the invention, which is explained purely by way of example with reference to the accompanying drawings, but not in a restrictive manner.

In the figures, a fine rake 1 is shown schematically, which is suitable to be installed in a water intake. Such a fine screen 1 can be installed by means of known and not shown fastening means or installation means in each water socket, then a water socket is available, the e.g. what looks like that which is shown schematically in Fig. 1. In this figure, the reference numeral 2 designates the water socket, which is described in the applicant's document AT 508 727 A1 and which, for removing water from a watercourse, is positioned in this watercourse that in the flow channel 3 of the water socket 2 a Water flow flows.

In Fig. 1 shows the foundation and support structure of Wasserfas solution 2, which is generally prepared as a concrete structure and arranged in a well-known manner in a watercourse. It comprises a main body and at its sides two shoulders 4, so that on the upper surface of the main body and between the shoulders 4 of Strö mungskanal 3 (in Fig. 1 only indicated) is formed, in which the What serströmung flows from the water is removed. In Fig. 1, only one shoulder 4 can be seen.

As is apparent from Fig. 1, the water intake 2 also includes a rough rake 5. The rough rake 5 forms a portion of the bottom of the flow channel 3 and serves in particular to excrete the larger foreign body.

The fine rake 1 is disposed below the Grobrechens 5 so that the the water flow taken water in the order of the Grobre chen 5 and the fine rake 1 flows through and then flows into a collecting channel 6, which is formed below the Feinrechens 1. This collection channel 6 is formed by two walls of different heights and a bottom on which the removed water flows away in order to reach the intended point of use.

The fine rake 1 has fine rake bars 7, 8, 9, 10, 11 arranged transversely to its longitudinal direction A. In the figures, a total of five Ausfüh were approximately examples of this fine rule bars 7; 8; 9; 10; 11, FIGS. 7; 8th ; 9; 10; 11 are arranged parallel to each other and close to each other, see e.g. Fig. 2, in which the embodiment is shown with the fine rule bars 7, that each pair of adjacent Feinre chenstäbe 7; 8th ; 9; 10; 11 delimited between each a fine index slot 12. In FIG. 2, by way of example only one of the fine rule bars has been designated by the reference numeral 7. In FIGS. 2, 4-8, only one of the fine-rule slots has been provided with the reference numeral 12. Each of the fine-rule slots 12 has an inlet opening 12a, the width of which, depending on the degree of excretion of the fine screen 1, is between 0.4 mm and 2 mm. A preferred value for this width is 0.6 mm. Widths that are larger than 2 mm are usually seen before for coarse rakes. Each fine-gauge slot 12 widens in the direction of its outlet opening 12b, because, as is apparent from Figs. 4-8, the outlet opening 12b has a width which is greater than the width of the inlet opening 12a.

The water which does not flow into the fine-particle grooves 12 flows along the fine-grain 1 and thereby determines a direction of flow which is represented by the arrow B in FIGS. 2, 4-8.

The fine rake 1 can be concave on its side directed toward the coarse rake 5 by having at least one concave section, see for example FIG. 1. Supporting means can also be provided, for example Side member 13; 14; 15, which support the fine rake 1 from below (see Figs. 2, 3, 9 and 10), since this 1 is not built as solid as a rough rake 5. It is also conceivable that the fine rake 1 not only ei nen concave Section but also has a subsequent convex portion (was not drawn in the figures), for example, to then extend straight.

The fine rake 1 is advantageously a rake which utilizes the Coanda effect referred to in the previous introduction. In order to make this possible, at least the part of each fine-particle bar 7 which is intended for the discharge of the withdrawn water and which comes into contact with the withdrawn water, has; 8th ; 9; 10; 11 a corner-free cross section. Which part of each fine rake 7; 8th ; 9; 10; 11, which forms according to the invention a part having a corner-free cross-section, will be described in more detail with reference to the exemplary embodiment of the spring rods 11 shown in FIG. 8, the terms below and above referring to the figure.

From Fig. 8 it is clear that the downwardly pointing Feinre chenstabsende has corners, so that the adjacent this end un tere part of the fine calculation rod 11 has no corner-free cross-section has. The o.g. Therefore, a corner-free part of each fine-grain bar 11 is made up of the remaining part of the fine-grain bar 11, which actually forms the main part of the fine-grain bar 11. This main part thus comprises both the upper end of the fine-grain bar 11 and the remaining part of the fine-grain bar 11 extending from top to bottom and the lower part. Thanks to its corner-free cross-section, this main part of the fine-grain bar 11 has edge-free surfaces on which the water flows and which, unlike the surface of the lower and lower end of the fine particles, face the flowing water.

The same considerations apply to the others shown in Figs four embodiments. In these embodiments, in which fine rake bars 7; 8th ; 9; 10 are provided, the contour of the entire cross section of each fine-grain bar 7; 8th ; 9; 10 advantageously cornerless.

In all embodiments, a first portion 7a, 8a, 9a, 10a, 11a of the contour of this corner-free cross-section extends along a direction which also has a component parallel to the longitudinal direction A of the fine rule 1 and directed in the flow direction B of the outflowing water. This first section 7a, 8a, 9a; 10a; 11a can be curved, in particular convexly curved, as is apparent from FIGS. 4-8. The presence of this first section 7 a; 8a; 9a; 10a; 11a ensures the Coanda effect comes into effect because, as long as the water is supported by the fine rod surface corresponding to sections 7a, 8a, 9a, 10a, 11a, gravity will not be able to detach the adhering water from the fine rake surface.

The contour of the corner-free cross-section also has a rounded projection 7 b; 8b; 9b; 10b; 11b, which is directed in the direction opposite to the flow direction B of the outflowing water and opposite to the first portion 7a, 8a, 9a, 10a, 11a. The water which is removed will thus flow along the edge-free fine-rake surface corresponding to the rounded projection 7b; 8b; 9b; 10b; 11b and the first section 7a, 8a, 9a, 10a, 11a.

As can be seen from FIGS. 4-8, a second section 7 c extends; 8c; 9c; 10c; 11 c of the contour of the corner-free cross-section along a direction which also has a parallel to the longitudinal direction A of the fine rule 1 and directed in the direction of flow B of the effluent water component. This second section 7c; 8c; 9c; 10c; 11c is followed by the rounded projection 7b; 8b; 9b; 10b; 11b. The second section 7 c; 8c; 9c; 10c; 11 c is not located on the same side of the Feinre chenstabes 7; 8th ; 9; 10; 11 on which the first section 7 a; 8a; 9a; 10a; 11 a is located, but on the other side. Also this second section 7c; 8c; 9c; 10c; 11c, like the first section 7a, 8a, 9a; 10a; 11 a, be curved, but he 7c; 8c; 9c; 10c; Like the first section 7a, 8a, 9a, 10a, 11a, 11c is not convexly curved but concavely curved.

The removed water dissolves from the respective fine atomizer 7; 8th ; 9; 10; 11 and falls into the underlying collecting channel 6 only when it has passed through the respective outlet opening 12b. Until then, the extracted water follows a path according to the dashed line F1, in the case of the embodiments of FIGS. 7-8, and the dashed lines F1 and F2 in the case of the embodiments of FIGS. 4-6. In the figures, the dashed lines F1 and F2 have been drawn by way of example only in one of the fine-angle slots 12.

The dashed line F1 shown in Figures 4-8 represents the way the water removed when flowing along the edge-free Feinre chenstaboberfläche travels that the rounded projection 7 b; 8b; 9b; 10b; 11b and the first section 7a; 8a; 9a; 10a; 11 a corresponds. The dashed line F2 shown only in Figures 4-6 represents the wide ren way that the water removed, after it has covered the path according to the line F1 and in the case of the three illustrated in these figures embodiments of the fine rule bars 7; 8th ; 9, covers. In these illustrated embodiments of the fine rule bars 7; 8th ; 9 is additionally provided that a third section 7d, 8d, 9d of the contour of the corner-free cross-section of each fine-grain bar 7; 8th ; 9 extends along a direction which also has a parallel to the longitudinal direction A of the fine rule 1 and directed in the direction of flow B of the outflowing water opposite direction component. This third section 7d; 8d; 9d is convexly curved and closes at the first section 7a; 8a; 9 a. Thus, the dashed line F2 represents the path traveled by the withdrawn water as it flows along the edge-free, fine-rake surface of the third section 7d; 8 d; 9 d corresponds.

Claims

1. Fine rake (1), which is suitable to be installed in a water intake (2), which (2), for the removal of water from a watercourse, is placed in the sem watercourse, and the (1) transverse to the longitudinal direction (A ) (7, 8, 9, 10, 11) are arranged parallel to each other and close to each other in such a way that each pair of adjacent fine-rule bars (7 ; 8; 9; 10; 11) defining between them a respective fine-gauge slot (12) having (12) an inlet opening (12a) whose width is less than 2 mm, the water not entering the fine-meshed slots (12) flows along the fine rake (1) and thereby determines a flow direction (B), characterized in that at least determined for the discharge of the withdrawn water and coming into contact with the withdrawn water part of each fine rake bar (7; 8; 9; 10; 11) has a corner-free cross section, wherein a ers section (7a; 8a; 9a; 10a; 11a) of the contour of this corner-free cross-section extends along a direction which also has a parallel to the longitudinal direction (A) of the fine rule (1) lying and directed in the direction of flow (B) of the effluent water component.

2. fine rake (1) according to claim 1, characterized in that the first portion (7a, 8a, 9a, 10a, 11a) is curved, in particular convexly curved.

3. fine rake (1) according to claim 1 or 2, characterized in that the contour of the corner-free cross section has a rounded projection (7b; 8b; 9b; 10b; 11b), which is directed in the direction of flow (B) of the outflowing water opposite direction and adjoining the first portion (7a; 8a; 9a; 10a; 11a).

4. fine rake (1) according to claim 3, characterized in that a second portion (7 c, 8 c, 9 c, 10 c, 11 c) of the contour of the corner-free cross-section extends along a direction which is also a parallel to the longitudinal direction (A 1) and directed in the flow direction (B) of the outflowing water component, and that the second section (7c; 8c; 9c; 1 Oc; 11c) adjoins the rounded projection (7b; 8b; b; 10b; 11b).

5. fine rake (1) according to claim 4, characterized in that the second portion (7 c, 8 c, 9 c, 10 c, 11 c) is concavely curved.

6. fine rake (1) according to claim 4 or 5, characterized in that each fine-gauge slot (12) has an outlet opening (12b) whose width is greater than the width of the inlet opening (12a).

7. fine rake (1) according to claim 6, characterized in that the contour of the entire cross section of each fine rake bar (7; 8; 9; 10) is free of corners.

8. Fine rake (1) according to claim 7, characterized in that a third section (7d, 8d, 9d) of the contour of the corner-free cross-section of each fine-grain bar (7; 8; 9) is convexly curved and extends along a direction which also has a component parallel to the longitudinal direction (A) of the fine rake (1) and directed in the opposite direction to the flow direction (B) of the effluent water, and that the third section (7d; 8d; 9d) adjoins the first section (7a; 8a, 9a).

9. fine rake (1) according to one of claims 1 to 8, character- ized in that at least a portion of the fine rake (1) concave is.

10. fine rake (1) according to one of claims 1 to 9, characterized in that at least a portion of the fine rake (1) is convex.

11. fine rake (1) according to one of claims 1 to 10, characterized in that the width of the inlet opening (12 a) of each fine-meshed slot (12) has a value which is between 0.4 mm and 2 mm, and in particular is 0.6 mm ,