FR2574113A1 - Helical rotating machine rotor - Google Patents
Helical rotating machine rotor Download PDFInfo
- Publication number
- FR2574113A1 FR2574113A1 FR8418514A FR8418514A FR2574113A1 FR 2574113 A1 FR2574113 A1 FR 2574113A1 FR 8418514 A FR8418514 A FR 8418514A FR 8418514 A FR8418514 A FR 8418514A FR 2574113 A1 FR2574113 A1 FR 2574113A1
- Authority
- FR
- France
- Prior art keywords
- blades
- rotor
- planes
- rotating machine
- allows
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Withdrawn
Links
- 238000005452 bending Methods 0.000 abstract description 4
- 230000003071 parasitic effect Effects 0.000 abstract description 2
- 239000012530 fluid Substances 0.000 description 3
- 230000005484 gravity Effects 0.000 description 3
- 239000000463 material Substances 0.000 description 2
- 239000002023 wood Substances 0.000 description 2
- 244000061520 Angelica archangelica Species 0.000 description 1
- 235000001287 Guettarda speciosa Nutrition 0.000 description 1
- 241000721662 Juniperus Species 0.000 description 1
- 235000014556 Juniperus scopulorum Nutrition 0.000 description 1
- 235000014560 Juniperus virginiana var silicicola Nutrition 0.000 description 1
- 235000008691 Sabina virginiana Nutrition 0.000 description 1
- 235000019506 cigar Nutrition 0.000 description 1
- 230000006835 compression Effects 0.000 description 1
- 238000007906 compression Methods 0.000 description 1
- 230000002596 correlated effect Effects 0.000 description 1
- 230000008878 coupling Effects 0.000 description 1
- 238000010168 coupling process Methods 0.000 description 1
- 238000005859 coupling reaction Methods 0.000 description 1
- 230000007423 decrease Effects 0.000 description 1
- 238000003754 machining Methods 0.000 description 1
- 230000002093 peripheral effect Effects 0.000 description 1
- 235000001520 savin Nutrition 0.000 description 1
- 239000007787 solid Substances 0.000 description 1
- 125000006850 spacer group Chemical group 0.000 description 1
- 238000011144 upstream manufacturing Methods 0.000 description 1
Classifications
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F03—MACHINES OR ENGINES FOR LIQUIDS; WIND, SPRING, OR WEIGHT MOTORS; PRODUCING MECHANICAL POWER OR A REACTIVE PROPULSIVE THRUST, NOT OTHERWISE PROVIDED FOR
- F03D—WIND MOTORS
- F03D1/00—Wind motors with rotation axis substantially parallel to the air flow entering the rotor
- F03D1/06—Rotors
- F03D1/0608—Rotors characterised by their aerodynamic shape
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
- F01D—NON-POSITIVE DISPLACEMENT MACHINES OR ENGINES, e.g. STEAM TURBINES
- F01D5/00—Blades; Blade-carrying members; Heating, heat-insulating, cooling or antivibration means on the blades or the members
- F01D5/12—Blades
- F01D5/14—Form or construction
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
- F01D—NON-POSITIVE DISPLACEMENT MACHINES OR ENGINES, e.g. STEAM TURBINES
- F01D5/00—Blades; Blade-carrying members; Heating, heat-insulating, cooling or antivibration means on the blades or the members
- F01D5/12—Blades
- F01D5/14—Form or construction
- F01D5/141—Shape, i.e. outer, aerodynamic form
- F01D5/146—Shape, i.e. outer, aerodynamic form of blades with tandem configuration, split blades or slotted blades
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F03—MACHINES OR ENGINES FOR LIQUIDS; WIND, SPRING, OR WEIGHT MOTORS; PRODUCING MECHANICAL POWER OR A REACTIVE PROPULSIVE THRUST, NOT OTHERWISE PROVIDED FOR
- F03D—WIND MOTORS
- F03D1/00—Wind motors with rotation axis substantially parallel to the air flow entering the rotor
- F03D1/06—Rotors
- F03D1/065—Rotors characterised by their construction elements
- F03D1/0658—Arrangements for fixing wind-engaging parts to a hub
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F03—MACHINES OR ENGINES FOR LIQUIDS; WIND, SPRING, OR WEIGHT MOTORS; PRODUCING MECHANICAL POWER OR A REACTIVE PROPULSIVE THRUST, NOT OTHERWISE PROVIDED FOR
- F03D—WIND MOTORS
- F03D3/00—Wind motors with rotation axis substantially perpendicular to the air flow entering the rotor
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F05—INDEXING SCHEMES RELATING TO ENGINES OR PUMPS IN VARIOUS SUBCLASSES OF CLASSES F01-F04
- F05B—INDEXING SCHEME RELATING TO WIND, SPRING, WEIGHT, INERTIA OR LIKE MOTORS, TO MACHINES OR ENGINES FOR LIQUIDS COVERED BY SUBCLASSES F03B, F03D AND F03G
- F05B2250/00—Geometry
- F05B2250/20—Geometry three-dimensional
- F05B2250/25—Geometry three-dimensional helical
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
- Y02E10/00—Energy generation through renewable energy sources
- Y02E10/70—Wind energy
- Y02E10/72—Wind turbines with rotation axis in wind direction
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
- Y02E10/00—Energy generation through renewable energy sources
- Y02E10/70—Wind energy
- Y02E10/74—Wind turbines with rotation axis perpendicular to the wind direction
Landscapes
- Engineering & Computer Science (AREA)
- Mechanical Engineering (AREA)
- General Engineering & Computer Science (AREA)
- Life Sciences & Earth Sciences (AREA)
- Sustainable Development (AREA)
- Sustainable Energy (AREA)
- Chemical & Material Sciences (AREA)
- Combustion & Propulsion (AREA)
- Physics & Mathematics (AREA)
- Fluid Mechanics (AREA)
- Wind Motors (AREA)
Abstract
Description
La présente invention concerne un rotor de machine tournante hélicoIdale, par exemple de ventilateur axial ou d'hélice éolienne. The present invention relates to a rotor of a helical rotary machine, for example of an axial fan or a wind propeller.
Pour ces rotors, munis d'un certain nombre de pales, on doit réaliser un compromis entre la résistance mécanique des pales, soumises à des forces de flexion et à des forces de torsion, et la vitesse spécifique, qui est le rapport de la vitesse tangentielle périphérique du rotor à la vitesse, loin en amont, du courant fluide axial. Ce compromis résulte dun certain nombre de contraintes. For these rotors, provided with a certain number of blades, a compromise must be achieved between the mechanical resistance of the blades, subjected to bending forces and to torsional forces, and the specific speed, which is the ratio of the speed peripheral tangential of the rotor at the speed, far upstream, of the axial fluid current. This compromise results from a number of constraints.
Tout d'abord, une des conditions pour obtenir le meilleur rendement possible est que le profil des pales présente une grande finesse, c'est-à-dire un rapport élevé entre le coefficient de portance et le coefficient de trainée. Ceci correspond, pour une famille de profils, à une épaisseur relative modérée, voisine de 12 * ou 15 * selon les familles. First of all, one of the conditions for obtaining the best possible yield is that the profile of the blades has great finesse, that is to say a high ratio between the lift coefficient and the drag coefficient. This corresponds, for a family of profiles, to a moderate relative thickness, close to 12 * or 15 * depending on the families.
La vitesse du fluide est en général une donnée sur laquelle on ne peut agir, et des considérations pratiques imposent le diamètre du rotor. The speed of the fluid is generally a datum on which one cannot act, and practical considerations impose the diameter of the rotor.
Or, lorsque le profil des pales, la vitesse du fluide et le diamètre du rotor sont fixés, la somme des cordes de ces paies ne dépend plus que de la vitesse spécifique. However, when the profile of the blades, the speed of the fluid and the diameter of the rotor are fixed, the sum of the strings of these pays only depends on the specific speed.
Elle décroît comme ltinverse du carré de celle-ci.It decreases as the inverse of the square thereof.
Donc une vitesse spécifique élevée correspond à une somme des cordes faible. So a high specific speed corresponds to a low sum of the strings.
Or les résistances mécaniques à la flexion et à la torsion dune pale sont daubant plus élevées que sa corde est grande. However, the mechanical resistance to bending and to torsion of a blade is higher than the length of its rope.
On est donc amené à choisir un nombre de pales faible, mais on se trouve le plus souvent limité dans cette voie à un rotor à trois pales au moins, dont lellipsotde d'inertie, en galette, évite les phenomènes de couplage entre les fréquences de résonance de la structure qui sert de support et la fréquence de rotation et ses harmoniques, phénomènes qui se produisent par exemple avec un rotor à deux pales dont ltellipsotde d'inertie est en forme de cigare. We are therefore led to choose a small number of blades, but we are most often limited in this way to a rotor with at least three blades, whose inertial lellipsotde, in wafer, avoids coupling phenomena between the frequencies of resonance of the structure which serves as support and the frequency of rotation and its harmonics, phenomena which occur for example with a rotor with two blades whose ltellipsotde of inertia is in the shape of a cigar.
Ainsi, il est clair que la vitesse spécifique, et par conséquent le régime de rotation se trouvent limités par la tenue mécanique des pales dans les rotors connus. Thus, it is clear that the specific speed, and consequently the rotation speed, are limited by the mechanical strength of the blades in the known rotors.
Il en résulte les inconvénients suivants
- poids et prix des machines élevés, sensiblement proportionnels au couple moteur, lui-même inversement proportionnel, à puissance donnée, au régime de rotation.The following disadvantages result
- high weight and price of the machines, appreciably proportional to the engine torque, itself inversely proportional, at a given power, to the rotation speed.
- poids et prix des engrenages multiplicateurs de vitesse de rotation éventuellement nécessaires. - weight and price of the multiplying gears of rotation speed possibly necessary.
- importance relative élevée des fluctuations de la vitesse axiale, et, en général, des turbulences et des phénom8nesncn stationnaires parasites, sources de vibration et de bruit. - high relative importance of the fluctuations of the axial speed, and, in general, of the turbulences and the parasitic stationary phenomena, sources of vibration and noise.
- importance relative élevée, dans le cas dune hélice éolienne, du gradient vertical de la vitesse du vent, des forces de gravité, des forces gyroscopiques, des écarts d'orientation. - high relative importance, in the case of a wind propeller, of the vertical gradient of wind speed, gravity forces, gyroscopic forces, deviations in orientation.
La présente invention vise à pallier ces inconvénients. The present invention aims to overcome these drawbacks.
Elle a pour objet à cet effet un rotor de machine tournante hélicoidale, caractérisé par le fait qu'il est doté de pales comprenant chacune au moins deux plans parallèles, et de moyens itassemblage agencés pour maintenir ces plans dans des positions relatives constantes. It has for this purpose a rotor of a helical rotating machine, characterized in that it is provided with blades each comprising at least two parallel planes, and itassembly means arranged to maintain these planes in constant relative positions.
Avec les pales de linvention, la résistance à la flexion et la résistance à la torsion ne sont plus limitées par l'épaisseur des profils, mais par le produit de cette épaisseur par la distance entre les plans, ou "entre-plan", lequel peut être aussi grand que l'on veut. With the blades of the invention, the flexural strength and the torsional strength are no longer limited by the thickness of the profiles, but by the product of this thickness by the distance between the planes, or "in-between", which can be as big as you want.
Ainsi la machine peut fonctionner à un régime de rotation plus élevé, toutes choses égales par ailleurs, puisque la tenue mécanique des pales est considérablement augmentée par les moyens d'assemblage. Thus the machine can operate at a higher speed, all other things being equal, since the mechanical strength of the blades is considerably increased by the assembly means.
La présente invention permet également, en choisissant convenablement les positions relatives et les poids des plans constitutifs de chaque pale, de placer le centre de gravité de celle-ci en avant du centre de torsion global, ce qui confère à la pale un meilleur comportement vis à vis -des vibrations de torsion, et réalise l'équiva- lent d'un lest du bord d'attaque, solution coûteuse pour régler ce problème sur les rotors connus à pales monoplanes. The present invention also makes it possible, by suitably choosing the relative positions and the weights of the planes constituting each blade, to place the center of gravity thereof in front of the overall center of torsion, which gives the blade better screw behavior. against torsional vibrations, and achieves the equivalent of a ballast of the leading edge, an expensive solution to solve this problem on known rotors with monoplane blades.
Enfin, la somme des cardes des plans d'une pale du rotor de l'invention restant égale à la corde de la pale du rotor connu qu'elle remplace, I'intérêt économique est important. Ainsi, dans le cas de pales biplanes
- les séries sont doublées
- la surface des moules ou des usinages est divisée
par deux
- la quantité de matière est réduite (de moitié, au
moins, dans la plupart des cas). Finally, the sum of the cards of the planes of a rotor blade of the invention remaining equal to the chord of the known rotor blade that it replaces, the economic interest is important. Thus, in the case of biplane blades
- the series are doubled
- the surface of the molds or machining is divided
by two
- the quantity of material is reduced (by half, at
less, in most cases).
L'invention sera mieux comprise à l'aide de la description suivante d'une forme de réalisation préférée du rotor selon l:tinvention, en référence aux dessins annexés, sur lesquels
- la figure 1 est une vue latérale dune pale, avec coupe partielle dans la zone d'encastrement au moyeu.The invention will be better understood with the aid of the following description of a preferred embodiment of the rotor according to the invention, with reference to the accompanying drawings, in which
- Figure 1 is a side view of a blade, with partial section in the area of fitting to the hub.
- la figure 2 représente une vue selon la coupe II-II de la figure 1 (plaque de garde non représentée). - Figure 2 shows a view along section II-II of Figure 1 (guard plate not shown).
La pale du rotor de machine tournante hélicoidale représentée sur la figure 1 comporte deux plans parallèles 1 et 2 à bords d'attaque 20, 22 et bords~de fuite 21, 23. The blade of the rotor of a helical rotating machine shown in FIG. 1 has two parallel planes 1 and 2 with leading edges 20, 22 and trailing edges 21, 23.
Ces deux plans parallèles sont maintenus dans des positions relatives constantes par, côté moyeu, une cale d'écartement 4, une tige filetée 5, et des écrous 6 et 7 qui assurent également la fixation de la pale aux flasques 8 et 9 du moyeu prévus à cet effet, au milieu de pale, par un mat torpédo 10 et en bout de pale, par une plaque de garde ou ginglet 11. These two parallel planes are held in constant relative positions by, on the hub side, a spacer 4, a threaded rod 5, and nuts 6 and 7 which also ensure the attachment of the blade to the flanges 8 and 9 of the provided hub. for this purpose, in the middle of the blade, by a roadster 10 and at the blade tip, by a guard plate or ginglet 11.
Le mat torpédo 10, est réuni aux deux plans 1 et 2 de façon à ménager des espaces 23 et 24 permettant une circulation d'air. The roadster mat 10 is joined to the two planes 1 and 2 so as to provide spaces 23 and 24 allowing air circulation.
Le plan inférieur 2, cwest-à-dire celui qui se trouve le premier exposé à la composante du vent perpendiculaire aux deux plans 1, 2 est décalé vers lavas par rapport au plan supérieur 1. The lower plane 2, ie that which is the first exposed to the component of the wind perpendicular to the two planes 1, 2 is shifted towards lavas with respect to the upper plane 1.
En vue d'améliorer le comportement de la pale k ltAgard des vibrations de torsion, des mesures sont prises pour que le centre de gravité se trouve en avant du centre de torsion. In order to improve the behavior of the blade at torsional vibrations, measures are taken so that the center of gravity is in front of the center of torsion.
On peut en particulier donner au plan inférieur 2 un poids plus faible qu'au plan supérieur 1. Ce résultat peut être obtenu en jouant sur les densités des matériaux utilisés dans le cas de profils pleins, ou sur les épais seurs de peau dans le cas de profils creux. In particular, the lower plane 2 can be given a lower weight than the upper plane 1. This result can be obtained by varying the densities of the materials used in the case of solid profiles, or the thick layers of skin in the case hollow profiles.
Par exemple, le plan supérieur 1 peut être réalisé en angélique, bois de densité forte, et le plan inférieur 2 en cèdre rouge, bois de densité faible. For example, the upper plane 1 can be made in angelica, high density wood, and the lower plane 2 in red cedar, low density wood.
Il en résulte en général une résistance mécanique plus faible pour le plan inférieur que pour le plan supérieur, qui permet d'égaliser les coefficients de sécurité des deux plans. This generally results in lower mechanical strength for the lower plane than for the upper plane, which makes it possible to equalize the safety coefficients of the two planes.
En effet, la vitesse d'écoulement est plus faible au droit du plan inférieur 2 qu'au droit du plan supérieur 1, le plan inférieur 2 travaille k la traction alors que le plan supérieur 1 travaille k la compression, et le plus faible poids du plan inférieur 2 peut être corrélatif dtune plus grande souplesse, ce qui réduit la proportion d'effort de flexion qu'il supporte. Indeed, the flow velocity is lower at the level of the lower plane 2 than at the level of the upper plane 1, the lower plane 2 works at traction while the upper plane 1 works at compression, and the lower weight of the lower plane 2 can be correlated with greater flexibility, which reduces the proportion of bending force that it supports.
Enfin, la forme de réalisation préférée ci-dessus du rotor de l'invention concerne des plans rectangulaires et non vrillés, mais il est clair que le rotor de l'invention peut être réalisé avec des pales de forme, de profil et de vrillage quelconques. Finally, the above preferred embodiment of the rotor of the invention relates to rectangular, non-twisted planes, but it is clear that the rotor of the invention can be produced with blades of any shape, profile and twist .
Claims (5)
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| FR8418514A FR2574113A1 (en) | 1984-12-05 | 1984-12-05 | Helical rotating machine rotor |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| FR8418514A FR2574113A1 (en) | 1984-12-05 | 1984-12-05 | Helical rotating machine rotor |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| FR2574113A1 true FR2574113A1 (en) | 1986-06-06 |
Family
ID=9310243
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| FR8418514A Withdrawn FR2574113A1 (en) | 1984-12-05 | 1984-12-05 | Helical rotating machine rotor |
Country Status (1)
| Country | Link |
|---|---|
| FR (1) | FR2574113A1 (en) |
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO1998031934A1 (en) * | 1997-01-20 | 1998-07-23 | Aerospatiale | Rotor with multiplane blades and wind power engine comprising such rotors |
| FR2798168A1 (en) * | 1999-09-03 | 2001-03-09 | Georges Jules Guerin | Dual rotor wind turbine for capturing wind energy, providing high-power compact turbine suited to mounting on vehicles, boats, houses or pylons |
| EP2078824A1 (en) * | 2008-01-10 | 2009-07-15 | Snecma | Double-blade with wings |
| CN102242693A (en) * | 2010-05-12 | 2011-11-16 | 陈显锋 | Wind wheel of wind driven generator |
Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US3195807A (en) * | 1958-10-20 | 1965-07-20 | Gen Dynamics Corp | Turbo-machine with slotted blades |
| GB2106193A (en) * | 1981-09-24 | 1983-04-07 | Rolls Royce | Turbomachine rotor blade |
| DE3207539A1 (en) * | 1982-03-03 | 1983-09-08 | Leo 6800 Mannheim Maniura | Propeller with two double blades - for a wind power plant |
-
1984
- 1984-12-05 FR FR8418514A patent/FR2574113A1/en not_active Withdrawn
Patent Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US3195807A (en) * | 1958-10-20 | 1965-07-20 | Gen Dynamics Corp | Turbo-machine with slotted blades |
| GB2106193A (en) * | 1981-09-24 | 1983-04-07 | Rolls Royce | Turbomachine rotor blade |
| DE3207539A1 (en) * | 1982-03-03 | 1983-09-08 | Leo 6800 Mannheim Maniura | Propeller with two double blades - for a wind power plant |
Cited By (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO1998031934A1 (en) * | 1997-01-20 | 1998-07-23 | Aerospatiale | Rotor with multiplane blades and wind power engine comprising such rotors |
| FR2758594A1 (en) * | 1997-01-20 | 1998-07-24 | Alexandroff Gregoire | IMPROVEMENTS ON BIROTORS AEROGENERATORS |
| FR2798168A1 (en) * | 1999-09-03 | 2001-03-09 | Georges Jules Guerin | Dual rotor wind turbine for capturing wind energy, providing high-power compact turbine suited to mounting on vehicles, boats, houses or pylons |
| EP2078824A1 (en) * | 2008-01-10 | 2009-07-15 | Snecma | Double-blade with wings |
| FR2926322A1 (en) * | 2008-01-10 | 2009-07-17 | Snecma Sa | DAWN BI-BLADE WITH BLADES. |
| US8021113B2 (en) | 2008-01-10 | 2011-09-20 | Snecma | Twin-airfoil blade with spacer strips |
| CN102242693A (en) * | 2010-05-12 | 2011-11-16 | 陈显锋 | Wind wheel of wind driven generator |
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| Date | Code | Title | Description |
|---|---|---|---|
| ST | Notification of lapse |