CA1278926C

CA1278926C - Wave generator

Info

Publication number: CA1278926C
Application number: CA000525016A
Authority: CA
Inventors: Pierre Guevel; Eric Landel
Original assignee: Individual
Current assignee: Individual
Priority date: 1985-12-11
Filing date: 1986-12-11
Publication date: 1991-01-15
Anticipated expiration: 2008-01-15
Also published as: DE3672483D1; EP0236653B1; EP0236653A1; ATE54354T1; ES2017639B3; BR8606163A; IN167898B; FR2602012B1; IL80882A0; KR870006319A; IL80882A; FR2602012A1

Abstract

1. System for generating an artificial surge or swell in an ocean engineering experimental basin or dock, of the type having a beater constituted by a cylindrical float parallel to the rear wall of the basin, characterized in that the section of said float, i.e. the generatrix of said cylinder, has a substantially vertical rear side, i.e. substantially parallel to said rear wall, and a nose-shaped front side, and said float is associated with mechanical means imparting to it a horizontal alternating movement, the mean distance between the rear wall of the float and the rear wall of the basin being chosen in such a way that a resonance phenomen is created between the swell train produced by the oscillations of the water column between said walls and that created by the movement of the float, the superimposing of these two trains giving rise to a very high transfer function in a chosen swell period interval.

Description

3~

La presante invention concerne url nouveau système generateur de houle, destine notamment aux bassins d'experimentation de genie océanique.

on sait qu'act.uellement il existe essentiellement deux types de generateurs de houle, ~ue l'on peut identifier en fonction de la nature de l'element "batt~ur" exercant son action dynamique sur la masse d'eau dans laquelle la houle artificielle doit être créee.

En premier lieu, on peut parler des batteurs du type "volet", pouvant se présenter comme un volet vertical animé d'un mouvement de translation alternatif, ou comme un volet incliné, animé d'un mouvement de basculement alternatif, ledit volet pouvant lui-même être articule et/ou couple a un dispositif de translation de son axe de basculement (volets à double effet).

~es etudes effectuées sur ces systèmes font apparaitre qu'ils n'assurent une fonction de transfert (rapport entre l'amplitude de la houle produite et l'amplitude de l'elongation angulaire du batteur) satisfaisante que pour des systèmes à double effet et pour des periodes de houle courtes. Au surplus~ sur le plan techni~ue, de tels systèmes sont peu attractif en raison de l'importance des masses à mettre en mouvement, des difficultés de pilotage simultané de deux vérins (translation et basculement) et des complexités techniques résultant des moyens nécessaires pour assurer l'étanchéité entre les volets et les parois laterales du canal.
En second lieu, on connaît les batteurs du type "coin plongeur", constitué par un prisme à section triangulaire orientée vers le bas, dont une grande face glisse d'un mouvement alternatif le long de la paroi verticale arrière du canal. La fonction de transfert de ces batteurs n'est pas non plus très satisfaisante et au surplus, ces batteurs ne sont pas adaptables au cas des bassins à houle de grande profondeur, à houle et courant.

Une solution nouvelle et plus satisfaisante a eté
suggéréa recemment par la deposante. Elle consiste à utiliser comme "batteur" un flotteur cylindrique horizontal, actionne en basculement sinusoidal selon l'un ou l'autre de ses trois degrés de liberté.

Bien que ce système conduise à des fonctions de transeert plus satisfaisante, il presente encore :L'inconvénient d'être coûteux, en raison des moyens complexes ~verin et embie]lage) utilisés pour actionner le batteur.

Or, on a fait la constatation intéressante que le même flotteur, animé cette fois simplement d'un mouvement alternatif horizontal, donc beaucoup moins coûteux, et disposé à une distance appropriée du mur arrière du canal, créee des houles presentant des fonctions de transfert beaucoup plus satisfaisantes encore que tous les systèmes connus.

Au surplus, il est avantageux, pour creer un phenomène de résonance, favorable à ces resultats, que l'arrière dudit flotteur soit vertical.

L'invention vise donc un générateur de houle constitué
par un flotteur cylindrique, monté transversalement dans un bassin, à faible distance de la paroi verticale arrière de ce bassin, la génératrice dudit cylindre présentant une partie arrière sensiblement verticale et une partie avant en forme de bec, ce cylindre étant associé à des moyeux lui imprimant une translation horizontale alternative.

Grâce à cette disposition, les organes mécaniques sont très simplifiés, puisque se ramenant à un vérin horizontal, et les efforts qu'ils doivent exercer sont très réduits.
L'invention va être decrite plus en détail grâce et avec référence au dessin ci-joint sur lequel:

3a La figure 1 est une coupe transversale schématique d'un système selon l'invention, et La figure 2 est un diagramme faisant apparaitre les variations de la fonction de transfert obtenue avec le système selon l'invention, selon la periode de la houle.

En se referant tout d'a~ord à la ~igure 1, on voit que, selon l'invention, un flotteur cylindrique 1 parallèle à la paroi arrière verticale 2 d'un bassin à houle, de manière en soi connue, est animee, au moyen d'un vérin 3 d'un mouvement dit de cavallement, c'est-à-dire de translation horizontale alternative.
La section de ce cylindre, c'est-à-dire sa genératrice, a la forme genérale representee sur la fi~ure, ~ savoir:

- sa face arri~re 4, c'est-à-dire faisant face à la paroi 2, est sensiblement verticale comme cette paroi. ~n verra plus loin les effets de cette particularite, ainsi que ceux de la distance entre les deux surfaces verticales;

- sa partie avant 5 est en forme de bec, faisant avec la surface S un angle , dont la valeur est un compromis entre une valeur la plus elevee possible, pour obtenir de bonnes performances en ce qui concerne la géneration de la houle, et une valeur faible, pour obtenir une bonne régularite de courant de c.irculation au ~voisinage dudit bec, dans le cas représenté, où un courant existe dans le canal, dans la direction F, le batteur 1 créant ainsi un convergent pour ce courant avec la dénivellation entre les fonds 6 et 6'.

L'expérience montre que, grâce à ce systeme, il est possible d'atteindre des fonctions de transferts très élevées, notamment pour les periodes de houle de l'ordre de 2 à 3 secondes. La figure 3 ~

The present invention relates to a new system.
swell generator, intended in particular for pools of ocean engineering.

we know that currently there are essentially two types of wave generators, ~ ue we can identify according of the nature of the "batt ~ ur" element exerting its dynamic action on the body of water in which the artificial swell must be created.

First, we can talk about drummers of the type "shutter", which can be presented as a vertical shutter animated by a reciprocating translational movement, or as an inclined flap, driven by an alternating tilting movement, said flap being able to itself be articulated and / or couple has a translation device of its tilting axis (double-acting flaps).

~ studies carried out on these systems show they do not have a transfer function (relationship between the amplitude of the swell produced and the amplitude of the elongation beater angle) satisfactory only for dual systems effect and for short swell periods. In addition ~ on the technically, such systems are unattractive due to the importance of the masses to set in motion, the difficulties of simultaneous control of two cylinders (translation and tilting) and technical complexities resulting from the means necessary to seal between the flaps and the side walls of the channel.
Secondly, we know the beaters of the "coin" type plunger ", consisting of a prism with a triangular section oriented downwards, a large face of which slides in an alternating movement along the rear vertical wall of the canal. The function of transfer of these drummers is also not very satisfactory and moreover, these beaters are not adaptable to the case of basins very deep swell, swell and current.

A new and more satisfactory solution has been suggested recently by the applicant. It consists in using as a "beater" a horizontal cylindrical float, operates in sinusoidal tilting according to one or other of its three degrees of freedom.

Although this system leads to transeert functions more satisfactory, it still presents: The disadvantage of being expensive, due to complex means ~ cylinder and embie] lage) used to operate the mixer.

Now, we made the interesting observation that the same float, this time simply reciprocated horizontal, therefore much less expensive, and arranged at a distance appropriate wall behind the canal, created swells with even more satisfactory transfer functions than all known systems.

In addition, it is advantageous to create a phenomenon of resonance, favorable to these results, that the rear of said float is vertical.

The invention therefore relates to a wave generator consisting by a cylindrical float, mounted transversely in a basin, at a short distance from the rear vertical wall of this basin, the generator of said cylinder having a rear part substantially vertical and a beak-shaped front part, cylinder being associated with hubs giving it translation alternative horizontal.

Thanks to this arrangement, the mechanical members are very simplified, since it boils down to a horizontal cylinder, and the efforts they have to exert are very reduced.
The invention will be described in more detail with and with reference to the attached drawing on which:

3a Figure 1 is a schematic cross section of a system according to the invention, and Figure 2 is a diagram showing the variations of the transfer function obtained with the system according to the invention, according to the period of the swell.

By referring all of a ~ ord to ~ igure 1, we see that, according to the invention, a cylindrical float 1 parallel to the wall vertical rear 2 of a swell pool, in known manner, is driven, by means of a jack 3 of a movement called cavalierly, that is to say of alternative horizontal translation.
The section of this cylinder, that is to say its generator, has the general form represented on the fi ~ ure, ~ namely:

- its rear face ~ re 4, that is to say facing the wall 2, is substantially vertical like this wall. ~ n will see later effects of this peculiarity, as well as those of the distance between the two vertical surfaces;

- its front part 5 is beak-shaped, making with the surface S an angle, whose value is a compromise between a value as high as possible, to obtain good performance in concerning the generation of the swell, and a low value, to obtain good regularity of circulating current at ~ neighborhood of said spout, in the case shown, where a current exists in the channel, in the direction F, the beater 1 thus creating a converge for this current with the difference in level between the funds 6 and 6 '.

Experience shows that, thanks to this system, it is possible achieve very high transfer functions, in particular for swell periods of the order of 2 to 3 seconds. The figure

2 illustre l'influence, sur les valeurs de ces fonctions de h~
3b transfert, de la distance de l'arrière du batteur au mur du bassin, c'est-à-dire les effets dus au phénomène, de resonance resultant de la variation cyclique de cette distance.

sur ce diagramme, les cour-bes I à VI correspondent à
différentes valeurs de moyenne temporelle de la clistance d, pour un batteur conforme à celui de la figure 1, ayant une largeur L à
la flottaison de 1,9 m, immergé de 1 m dans un bassin dont le fond 6 est à 7 m et le fond 6' est à 3 m, la distance D étant de 10 m:

Courbe d movenne (m) 15I 0,6 II 0,7 III 0,8 IV 0,9 V 1,9 .
20VI 2,0 Ces courbes sont à rapprocher de la courbe A, illustrant les variations de la fonction de ~ransfert obtenue avec un flotteur semblable, mais animé d'un mouvement oscillant autour d'un axe transversal X.

Il peut ressortir que, les fonctions de transfert obtenues avec le système selon l'invention sont les plus favorables dans le domaine des périodes souhaitables pour les bassins considerés; cela montre au surplus que les performances hydrodynamiques de ce système sont tout à fait différentes de celles des systèmes antérieurs les plus comparables du point de vue géométrique.

Il convient egalement de bien.observer que, bien que ces résultats découlent de phénomène de résonance précité, lui-même ~.~'7~

cree par l'effet de piston joue par le flotteur sur la masse d'eau entre sa face arrière et le mur du ba.ssin, ce qui im-plique la verticalite de cette face arrière, il est possi-ble, dans le cadre de l'invention, de rea:Liser un flotteur dont ladite face arrière soit legèrement inclinee vers l'avant par rapport a la verticale. On obtient alors comme resultat supplementaire une limitation du clapot entre le mur et le flotteur, sans pour autant diminuer la fonction de transfert.
Il resulte de ce qui precède que le nouveau sys-tème generateur de houle selon l'invention presente un ensem-ble de caracteristiques nouvelles et interessantes:
- fonction de transfert elevee - simplicite du système mecanique - bonne compatibilite avec les imperatiEs lies à la generation du courant dans le bassin - faibles efforts hydrodynamiques exerces par le flotteur sur le verin, du fait d'une masse d'eau ajoutee negative au voisinage de la periode de resonance (2 à 30), ce qui permet de limiter les efforts d'inertie que le verin doit developper pour actionner le flotteur~

La presente invention peut être appliquee aux domaines de l'equipement de loisirs, tels que piscines publi-ques ou privees, centres aquatiques et analogues.

Un exemple detaille d'une telle application se re-ferant à la figure 1 est donne ci-après:

Selon cet exemple, une installation generatrice de houle conforme a celle decrite a la figure 1 du brevet prin-cipal a ete montee dans un bassin rectangulaire de 18 x 50 metres, de profondeur constante de 2 mètres, sans circula-tion d'eau. 2 illustrates the influence, on the values of these functions of h ~
3b transfer, from the distance from the back of the mixer to the wall of the pool, i.e. the effects due to the phenomenon, resulting resonance of the cyclic variation of this distance.

on this diagram, the cour-bes I to VI correspond to different time average values of the clistance d, for a mixer according to that of FIG. 1, having a width L to the buoyancy of 1.9 m, immersed by 1 m in a basin whose bottom 6 is 7 m and the bottom 6 'is 3 m, the distance D being 10 m:

Movenne curve (m) 15I 0.6 II 0.7 III 0.8 IV 0.9 V 1.9.
20VI 2.0 These curves are to be compared to curve A, illustrating variations in the ~ ransfert function obtained with a float similar, but with an oscillating movement around an axis transverse X.

It can be seen that the transfer functions obtained with the system according to the invention are the most favorable in the area of desirable periods for basins considered; it also shows that the performances hydrodynamics of this system are quite different from those of the most comparable prior systems geometric.

It should also be noted that, although these results arise from the aforementioned resonance phenomenon, itself ~. ~ '7 ~

created by the piston effect played by the float on the mass of water between its rear face and the wall of the ba.ssin, which im-plique the verticality of this rear face, it is possible ble, in the context of the invention, to rea: Read a float the said rear face of which is slightly inclined towards the front with respect to the vertical. We then obtain as additional result a limitation of the chop between the wall and float, without reducing the function transfer.
It follows from the above that the new system swell generator according to the invention has a set of ble of new and interesting features:
- high transfer function - simplicity of the mechanical system - good compatibility with related imperatIes generating the current in the basin - weak hydrodynamic forces exerted by the float on the cylinder, due to an added body of water negative in the vicinity of the resonance period (2 to 30), which allows to limit the inertia efforts that the actuator must develop to activate the float ~

The present invention can be applied to leisure equipment, such as public swimming pools ques or private, aquatic centers and the like.

A detailed example of such an application is doing in Figure 1 is given below:

According to this example, an installation generating swell conforms to that described in FIG. 1 of the main patent cipal was mounted in a rectangular basin of 18 x 50 meters, of constant depth of 2 meters, without circulation tion of water.

3~i Cette installation comporte un batteur 1 d'une longueur L à la flottaison de 1,914 mètre, dont la face arriere 4, faisant face au mur arriere 2 du bassin est plane et verticale, d'une hauteur de 0,50m sous la surface libre S.

Le fond du batteur 1 est constitue d'un cylindre horizontal de centre ~ et de rayon 0,50 m. Le tirant d'eau du generateur est donc de 1 metre. La partie avant du bat-teur consiste egalement en un cylindre dont le rayon est 1,50 metre et le centre est situe a 1 metre verticalement au-dessus de X. L'angle alpha a la flottaison est de 60.

La distance moyenne d de la face arriere 4 au mur 2 varie de 0,60 a 1 metre~

On excite le batteur au moyen d'un v~rin hydrauli-que 3 qui lui imprime un mouvement sinusoidal d1une periode variant de 1 a 3 secondes et d'une amplitude de 0,37 metre.
Pour une distance d = 0,8 metre, on peut obtenir des houles de 1 metre de hauteur, de 1,4 secondes de periode et de 0,37 d'amplitude, correspondant a des houles frequemment rencon-trees dans la nature.

Pour equiper une piscine ayant une largeur compri-se entre 3 et 33 metres, d'une longueur comprise entre 30 et 100 metres, selon sa forme, et d'une profondeur de 0,5 a 3 metres, les parametres imposes sont les suivants:

La distance D moyenne entre le mur arriere de la piscine et la face arriere du flotteur doit être comprise entre 0,1 a 2 metres.

7~

La longueur à la flottaison du flotteur doit être comprise entre 0,25 et 3 metres.

L'angle a]pha du bec du flotteur doit être compris entre 15 et 30 degres.

Le tirant d'eau, clest-a-dire la hauteur immergee du flotteur doit être compris entre 0,1 et 2 metres.

La période d'excitation du flotteur, c'est-a-dire du mouvement sinusoidal qui 1ui est impose, doit être comprise entre 0,5 et 4 secondes et, L'amplitude de ce mouvement sinusoidal doit être lS comprise entre 0,05 et 1,5 metres.

Il est indique également au brevet principal que la hauteur au-dessus de la surface du bain du mur arrière de la piscine et de la face arriere du flotteur, doit être un peu plus elevee que les hauteurs des autres elements de la piscine et du flotteur. Il est bien entendu qu'il s'agit-la d'une precaution supplementaire, pratiquement pour eviter le debordement de l'eau dans la zone situee entre le flotteur et le mur ou prennent naissance les phenomenes sur lesquels repose l'invention.

Bien entendu, les parametres pourront être modi-fies de maniere a obtenir des houles de caracteristiques differentes. 3 ~ i This installation comprises a mixer 1 of a length L at the waterline of 1,914 meters, the face of which rear 4, facing the rear wall 2 of the pool is flat and vertical, from a height of 0.50m below the free surface S.

The bottom of the beater 1 consists of a cylinder horizontal with center ~ and radius 0.50 m. The draft of the generator is therefore 1 meter. The front part of the bat-tor also consists of a cylinder whose radius is 1.50 meter and the center is located 1 meter vertically above X. The alpha angle at the waterline is 60.

The average distance d from the back side 4 to the wall 2 varies from 0.60 to 1 meter ~

The beater is excited by means of a hydraulic rinse that 3 which gives it a sinusoidal movement of a period varying from 1 to 3 seconds and with an amplitude of 0.37 meter.
For a distance d = 0.8 meters, swells can be obtained 1 meter high, 1.4 seconds per period and 0.37 amplitude, corresponding to swells frequently encountered trees in nature.

To equip a swimming pool with a compri-between 3 and 33 meters, with a length between 30 and 100 meters, depending on its shape, and a depth of 0.5 to 3 meters, the parameters imposed are as follows:

The average distance D between the rear wall of the pool and the back of the float must be included between 0.1 to 2 meters.

7 ~

The float length of the float must be between 0.25 and 3 meters.

The angle a] pha of the float nozzle must be understood between 15 and 30 degrees.

The draft, ie the submerged height float must be between 0.1 and 2 meters.

The period of excitation of the float, i.e.
of the sinusoidal movement which is imposed upon it, must be between 0.5 and 4 seconds and, The amplitude of this sinusoidal movement must be lS between 0.05 and 1.5 meters.

The main patent also states that the height above the bath surface of the rear wall of the pool and the back of the float, must be a little higher than the heights of the other elements of the pool and float. It is understood that this is the an extra precaution, practically to avoid the water overflow in the area between the float and the wall where the phenomena on which arise rests the invention.

Of course, the parameters can be changed so as to obtain characteristic swells different.

Claims

1) Artificial wave generator system in an ocean engineering experimental pool, of the type comprising a mixer constituted by a float cylindrical parallel to the rear wall of the basin, characterized in that the section of said float is ie the generator of said cylinder, has one side substantially vertical rear, i.e. substantially parallel to said rear wall, and a front side in beak shape, and said float is associated with means mechanical giving it reciprocating motion horizontal.

2) System according to claim 1, characterized in that the average distance from the rear wall of said float and the rear wall of said basin is chosen in such a way that a phenomenon of resonance between the swell train caused by oscillations of the water column between said walls and that created by the proper movement of the float, the superposition of these two trains giving birth to a very high transfer function in an interval chosen from the swell period.

3) System according to claim 1 characterized in that, in order to limit the chop between the wall and the float, the back side of the float is slightly tilted forward from the vertical.

4) System according to claim 2 characterized in that, in order to limit the chop between the wall and the float, the back side of the float is slightly tilted forward from the vertical.

5) System according to claim 1 characterized in that it is installed in a swell basin and current.

6) System according to claim 2 characterized in that it is installed in a swell basin and current.

7) System according to claim 3 characterized in that it is installed in a swell basin and current.

8) System according to claim 4 characterized in that it is installed in a swell basin and current.

9) Wave generator system according to claim 1, applied to the field of equipment leisure, such as public or private swimming pools, centers analogous aquatic.

10) Artificial wave generator system according to claim 1, adapted to a swimming pool having a length between 30 and 100 meters, a width between 8 and 33 meters, a depth between between 0.5 and 3 meters, characterized in that the distance average between the rear wall of the pool and the face rear of the float is between 0.1 and 2 meters, float length is included between 0.5 and 3 meters, the angle formed by the front spout of the float is between 15 and 90 degrees, pulling it float water is between 0.1 and 2 meters, and the characteristics of the sinusoidal movement imposed on the float are a period between 0.5 and 4 seconds and an amplitude between 0.05 and 1.5 meter, the basin having a depth of between 0.5 and 3 meters.