EP1382855A2 - Turbomachine with integrated fluid recirculation system - Google Patents

Abstract

The machine which operates with a fluid flow, e.g. at a blower or compressor or fan or pump and the like, has at least one rotor (1) and a freely-selected number of stators (2) in the fluid flow path, with at least one paddle. A system to extract and return fluid into the flow path is at the surface defining the paddle channel, in a bi-functional structure, with at least one feedback channel (4) with throttles (5) to return extracted fluid to an upstream position in the flow path, and at least one additional channel to lead fluid out of a downstream position in the flow path. The fluid can be a gas or a liquid.

Description

The invention relates to a fluid flow machine with an integrated fluid circulation system.

The aerodynamic load capacity of components of a fluid flow machine, for example, wind instruments, compressors, Pumps and fans, through the growth and the separation of profile boundary layers on the blade surfaces and the sidewall boundary layers on the hub and the housing are formed, limited.

The state of the art shows for fans, compressors and pumps Fans only conditionally concepts for internal guidance of a sucked on particularly advantageous places fluid and its Re-feeding at particularly advantageous locations in the Main flow path.

In most cases, the prior art shows solutions, in which an extracted fluid amount either under utilization an existing pressure gradient or with the help of an external pressure gradient Pump permanently removed from the main flow path of the fluid becomes. This happens either at the axial gap between two Blade rows or on surfaces of the blade row itself. There are also solutions in which fluid at the axial gap or a blade row is supplied from an external source.

There are also known individual solutions in which a continuous Fluid circulation only on a single Shovel, for example a rotor blade, takes place on which Sucked fluid from the surface and at the same Shovel is blown again in the blade tip area.

Other concepts known in the art see one non-continuous recirculation of the fluid from the rear to the front stages of a compressor before to the stage detuning to influence at partial load operation. In these Cases, the exchange of fluid is limited to the between the blade rows of the turbomachine lying Axial gaps.

Also state of the art are individual solutions, the one continuous fluid circulation between different Provide blade rows of a compressor. Here is with help the existing pressure drop on a downstream blade row or a local axial gap fluid removed and on an upstream row of blades fed again.

A suction on rotors and stators and a derivative of the Fluids to a location outside the flow paths of the flow machine show US 2,720,356 and US 5,904,470, EP 1 013 937 A2 and DE 1 815 229 A.

From US 5,480,284 is a continuous fluid circulation previously known within individual rotor blades.

A continuous recirculation of fluid between axial gap and blade row is known from DE 1 428 188 A, while a recirculation of blade row to blade row in US 2,749,027, US 2,933,238 and US 2,870,957.

The solutions known from the prior art are distinguished through a number of significant disadvantages.

Some of the existing concepts by boundary layer extraction or fluid injection additional stabilization wanting to reach the flow in the flow machine, let the aspect of a circulation of the secondary fluid quantities between surfaces of different blade rows of Turbomachine is disregarded. Mostly fluid - In some cases, even with the application of additional energy - permanently removed from the main flow path or from external Source supplied.

Both additional energy and loss Causing mass flow through the turbomachine Losses for the thermodynamic process of the fluid flow machine surrounding overall system. Such overall systems For example, gas turbines, aircraft engines power plants or something similar. Use isolated concepts a recirculation from blade row to blade row, yet each row of blades is used either alone the fluid removal or the fluid supply.

None of the existing concepts looks the same Blade row a bifunctional flow control, d. H. a combination of fluid removal and fluid delivery and thus a highly effective combination of boundary layer extraction and Blowing in before. An integrated circulation system for one repetitive realization of the bifunctional flow control over several stages of the fluid flow machine it also not.

The invention is based on the object, a fluid flow machine to create, which in a simple structure, lower Number of parts and cost-effective manufacturability while avoiding the disadvantages of the prior art a particular has high aerodynamic load.

According to the invention, the object is achieved by the feature combination of the main claim, the dependent claims show further advantageous embodiments of the invention.

The present invention relates to fluid flow machines like blowers, compressors, pumps and fans in axial, semi-axial or radial design with gaseous or liquid working medium (fluid). The flow machine consists of one or more stages. Each stage usually includes a rotor and a stator, in some cases exists only a rotor. The rotor consists of one Number of blades connected to the rotating shaft of the Turbomachine are connected and energy to the working fluid submit. The rotor can be with or without shroud on be executed outer blade end. The stator is in turn from a number of fixed blades, either on both ends with shroud or hub side with free Can be performed blade end. The flow machine is usually surrounded by a housing, in others Cases (eg in propellers or propellers) exists no housing. The turbomachine can be a stator before the first rotor (leading wheel). Alternatively to this can be rotatably mounted at least one stator or Vorleitrad be and for adjustment an accessible from outside the housing Spindle have. In a special embodiment can the turbomachine also at least one row having adjustable rotors.

In an alternative configuration, said turbomachine in multistage, have two opposite waves, so that the rotor blade rows from stage to stage the Change the direction of rotation. There are no stators between successive rotors. Finally, the Fluid flow machine such a bypass configuration have that the single-flow annular channel behind a the blade row divides into two concentric ring channels, which in turn accommodate at least one row of blades each.

According to the invention, at least one blade row (rotor or stator) of the fluid flow machine both a device for removing fluid from the main flow path as also a device for supplying fluid into the main flow path provided (bifunctional flow control). At least one exists in connection with the removal device a conduit for returning the withdrawn fluid a further upstream location on the main flow path. The supply device, however, is connected to at least one line connected to the from a further downstream position Fluid is returned at the main flow path. According to the invention extends this principle of action when linking several rows of blades to an integrated fluid circulation system repetitive over several stages of the turbomachine.

The central object of the invention is thus an integrated System for continuous fluid circulation, which is a bifunctional Flow control on at least one row of blades allows and therefore, in terms of concept, the effectiveness and the reuse along several stages the fluid flow machine of the prior art differentiates known solutions.

According to the invention, at least one blade row of the Turbomachine both at least one device for fluid withdrawal as well as at least one device for Provided fluid supply to Schaufelkanalbegrenzenden surfaces. Preferably, this feature is over several Blade rows such that a means for fluid removal on at least one blade of at least one stator or Rotor row via at least one line to a device to the fluid supply opens, located at an upstream Place the flow path on at least one blade of at least one stator or rotor row is located.

The inventively provided lines can either a allow free flow of the fluid or alternatively with a fixed or variably controllable throttle body provided be.

Furthermore, it may be convenient if the line to the collection of withdrawn fluid quantities of individual blades of the fluid flow machine with a preferably on the periphery of the main flow path, in which individual lines lead or from which or the go out several lines. In the same way, a supply chamber be provided. Both the discharge chamber and the supply chamber serve to equalize the fluid flow and a corresponding, if necessary Pressure compensation.

Fig.1

eine schematische Darstellung der aus dem Stand der Technik bekannten Lösungen zur Fluidentnahme oder Fluidzufuhr,

Fig. 2

eine schematische Darstellung der aus dem Stand der Technik bekannten Lösungen zur Fluidzirkulation,

Fig. 3

eine Darstellung einiger möglicher Konfigurationen der Strömungsarbeitsmaschine

Fig. 4

die Definition der schaufelkanalbegrenzenden Oberflächen, erforderlich zum Verständnis der Erfindung,

Fig. 5

eine schematische Darstellung des erfindungsgemäßen Lösungskonzeptes,

Fig. 6

ein Ausführungsbeispiel des erfindungsgemäßen Fluidzirkulationssystems,

Fig. 7

ein alternatives Ausführungsbeispiel, analog Fig. 6,

Fig. 8

ein Ausführungsbeispiel mit variabler Leitschaufelgestaltung.

In the following the invention will be described by means of embodiments in conjunction with the drawing. Showing:

Fig.1

a schematic representation of the known from the prior art solutions for fluid removal or fluid supply,

Fig. 2

a schematic representation of the known from the prior art solutions for fluid circulation,

Fig. 3

a representation of some possible configurations of the fluid flow machine

Fig. 4

the definition of the blade channel limiting surfaces necessary for understanding the invention,

Fig. 5

a schematic representation of the solution concept according to the invention,

Fig. 6

an embodiment of the fluid circulation system according to the invention,

Fig. 7

an alternative embodiment, analogous to FIG. 6,

Fig. 8

an embodiment with variable vane design.

Fig. 1 shows a schematic representation of the Prior art known solutions for fluid removal or Fluid supply. It can be seen that a blow-off of fluid either from a rotor or a stator (rotor or stator blade) done away from the flow machine. there An auxiliary pump 3 can be used. Furthermore is it is known from an external source, for example one To supply auxiliary pump, a rotor or stator fluid.

Fig. 2 describes further solutions according to the prior Technology. These include recirculation between axial gaps, the recirculation between axial gap and blade row (rotor or stator), as well as the recirculation between rows of blades (Rotor or stator).

Fig. 3 shows the scope of the present invention to clarify some possible configurations of the Main flow path of the flow machine according to the invention with integrated fluid circulation system.

Fig. 4 shows the definitions of the invention used Concept of "shovel-channel-limiting surfaces". there is, as is apparent from the caption of Fig. 4, a different arrangement and dimensioning of the individual Areas provided.

Fig. 5 shows a schematic representation of a possible Embodiment of the inventive concept with a continuous Fluid circulation. It can be seen that here Circulation lines alternately between rotors 1 and stators 2 are provided to the blade rows according to the invention To give bifunctionality. By means of the schematic shown line 4, it is possible in each case, fluid suck off or remove and at a location upstream of the flow path to direct the flow machine to it there feed again. The fluid removal and supply can either on a rotor or on a stator (or on a respective Shovel thereof), wherein the fluid by in detail not shown recesses in blades of the rotor or stator enters or exits. As shown in FIG. 5, can line 4 connect either stators or rotors, however, it is also possible to use fluid from a rotor remove and supply to a stator or from a stator to and deliver it to a rotor for bifunctionality (Fluid withdrawal and supply simultaneously) one or more To ensure rows of blades. The type of fluid supply in the main flow path upstream of a bifunctional supplied Blade row or a sequence bifunctional supplied Blade rows is how the type of fluid removal from the Main flow path downstream of a bifunctional supplied Blade row or a sequence bifunctional supplied Blade rows, freely selectable.

Alternatively, it is also possible in the line 4, a throttle body 5 provide, which optionally variably adjustable is to the inventive design to different Adjust operating conditions of the turbomachine to be able to.

According to the invention, the removal of fluid from the flow path the Strömungsarbeitsmaschine by Schaufelkanalbegrenzende Surfaces on at least one blade at least a rotor or stator row 1, 2 connected to a collection and guiding the fluid to at least one further upstream located blade row, connected to a supply of the Fluids in the flow path of the fluid flow machine through blade channel limiting surfaces on at least one Blade of a rotor or stator row 1 or 2. It takes place the transfer of the fluid from the sampling point to the feed point by means of the line 4 at free line / chamber flow cross-section or in a restricted manner via an optionally modulatable throttle element 5 in the transfer path or in the line 4. According to the invention, the circulation system always in such a way that at least one Blade of a rotor or stator row by simultaneous Presence of a donor site and a feeding site one bifunctional flow influencing possible, and thus bifunctionality is made.

Schaufelkanalbegrenzende surfaces according to the present Invention are as shown in Fig. 4, all surfaces of a Shovel itself (suction side, pressure side, front edge and Trailing edge), surfaces on the hub and housing of the turbomachine with a location between the leading and trailing edges of the considered blade row, surfaces on hub or Housing with fixed connection to the blade (blade platforms, Shrouds, blisk or bling configurations) between a location 25% of the local meridional blade chord length (CmG or CmN) located in front of the leading edge and the leading edge itself, surfaces on the hub or housing without a fixed connection to the bucket (free rotor or stator ends) between one Location 35% of the local meridional blade chord length (CmG or CmN) located in front of the leading edge and the leading edge even.

In the following, the embodiments of FIGS. 6 and 7 received.

Fig. 6 shows an on or in a not further detail illustrated housing of the flow machine trained Fluid discharge chamber 6 with arbitrary shape, which is connected to the line 4 and at least one Opening on blade channel limiting surfaces at least a blade of a stator or a stator 2 in conjunction stands. Furthermore, it can be seen that the line 4 is formed in the region of the housing and a transfer path forms. It is at least one line 4 and / or one Discharge chamber 6 is provided. The line 4 opens into an or located on the housing fluid supply chamber 7, which in terms their dimensioning and shaping ausgestaltbar is and communicates with at least one opening on one shovel channel limiting surface at least one Blade of a further upstream stator row or a stator 2. For the realization of the bifunctionality according to the invention has at least one blade at least one the integrated into the fluid circulation system stator rows a Number of openings on the shroud-channel limiting surfaces of which a part with a discharge chamber 6 and the remaining part is connected to a supply chamber 7.

Alternatively or in combination thereto, FIG. 6 shows in their lower half of the illustration a variant embodiment, in which the discharge chamber 6, the lines 4 and the Supply chamber 7 individual rotor rows are assigned. The wires 4 are in this case in or on the rotor drum or formed the hub of the rotor. For the realization of the invention Bifunctionality has at least one scoop at least one of the integrated into the fluid circulation system Rotor rows a number of openings on Schaufelkanalbegrenzenden Surfaces on, of which a part with a discharge chamber 6 and the remaining part with a supply chamber. 7 connected is.

FIG. 7 shows an alternative embodiment in which a fluid discharge chamber located in or on the rotor drum 6 selectable shape is associated with at least one Opening on a blade channel limiting surface at least a blade of a row of stator 2. Furthermore, a in the rotor drum 1 located transfer path (line 4) from at least one line and / or a chamber selectable Form provided, which communicates with fluid discharge chamber 6. In or on the rotor drum is a fluid supply chamber 7 selectable shape formed, which in conjunction is at least one opening at a Schaufelkanalbegrenzenden Surface of at least one blade of a further upstream stator row 2. To realize the bifunctionality of the invention has at least one Blade of at least one of the incorporated in the fluid circulation system Stator rows a number of openings on Schaufelkanalbegrenzenden Surfaces on, of which a part with a Discharge chamber 6 and the remaining part with a supply chamber 7 is connected.

Furthermore, Fig. 7 shows an alternative or additional Embodiment in which a located in or on the housing Fluid discharge chamber 6 selectable shape with at least an opening on a blade channel limiting surface at least one blade of a rotor row 1 in conjunction stands. In or on the housing is a transfer path (line 4) is formed. This includes, as with the others Embodiments, at least one line and / or a Chamber of selectable shape, which is associated with at least an opening on Schaufelkanalbegrenzenden surfaces at least one blade of a further upstream Rotor series 1. For the realization of the bifunctionality according to the invention has at least one blade at least one of in the fluid circulation system integrated rotor rows a number of openings on Schaufelkanalbegrenzenden surfaces of which a part with a discharge chamber 6 and the remaining part with a supply chamber 7 is ally.

As is apparent from the foregoing, are in accordance with the invention most different configurations and assignments the fluid recycling possible to bifunctionality on one or produce several rows of blades. Either, as in Fig. 6 and Fig. 7 shown, from rotor to rotor or from stator to stator, or from rotor to stator or from stator to rotor, with the line 4 either on or in the housing or on or in the rotor drum (hub) can be trained. Furthermore, it follows that the return the fluid also includes options in which the fluid continues as the next following rotor or stator is returned. There are thus a variety of combinations within the scope of the invention possible.

Fig. 8 shows an embodiment with a variable Stator vane of a stator 2, which is also a Vorleitschaufel can be. This invention has the above-described bifunctional construction. The stator blade consists of a profiled airfoil and one connected to this Spindle passing through the housing of the fluid flow machine leads to the outside and there the connection to any Adjustment mechanism allows. The spindle 8 is at its own Axis rotatably mounted on or in the housing and has a any cross-sectional profile along its axis. The Spindle is hollow inside and points along its entire length or over parts of their length two next to each other or into each other lying on channels. One of said channels of the spindle 8 serves the fluid supply to the blade and has for this purpose a side or head-side inlet, which is the inflow from the fluid supply chamber 7 allows. For further fluid guidance this spindle channel is at least one cavity in the blade interior with at least one opening on surfaces the variable stator blade in connection. The other one said Spindle channels has at least one cavity in the Bucket interior with at least one opening on surfaces of variable stator blade in conjunction. This spindle channel serves the fluid discharge from the blade and has to this Purpose a side or head outlet, which is the outflow in the fluid discharge chamber 6 allows. Warehousing the spindle 8 in the housing can be either directly or via at least a slide bushing done. In the embodiment shown a total of three bushings are provided.

Alternatively to the solution shown in FIG. 8, a variable, bifunctional stator blade according to the invention in addition to the Spindle with storage on the housing another, internal Spindle with storage in a fixed area on the hub the Strömungsarbeitsmaschine have. Then it can be beneficial be the fluid drain via an outward to the housing leading spindle channel and a related Allow discharge chamber on the housing, but the fluid supply via a coming from the hub spindle and a channel to ensure that it is connected to the hub. It may also be advantageous to supply the fluid via a coming from the housing spindle and a channel to allow a communicating supply chamber on the housing but the fluid drainage via an inward leading to the hub Spindle channel and an associated discharge chamber to ensure at the hub. Finally, according to the invention during storage of the spindle in the area of the hub and independently from the presence or absence of an external one Spindle, the fluid supply and the fluid drain over next to each other or in each other, leading to the hub Spindle channels and also fluid supply at the hub and discharge chambers are ensured. In this case apply the previously for the case "fluid supply and fluid removal at the housing" established design rules.

As can be seen from the above explanations, allows the flow machine according to the invention with the inventive Fluid circulation system a previously unattained Level of active boundary layer influence in fluid flow machines of different design, such as brass, Compressors, pumps, fans, propellers and Propellers.

The fluid circulation system according to the invention operates continuously active and leads over a wide operating range of Turbomachine to a strong increase in aerodynamic Resilience.

Furthermore, the embodiment of the invention provides a significant tighter dimensioning of the entire turbomachine. The fluid circulation system according to the invention is self-driving and does not require energy from outside the flow machine. Through the complete internal circulation of fluid becomes a fluid mass loss between inlet and outlet of the fluid flow machine avoided. It will thus be an effective reuse the extracted fluid elsewhere in the fluid flow machine allows.

The invention further has the advantage that in particular by the bifunctionality of the invention or one several rows of blades a very intensive exchange of fluid reached between Schaufelkanalbegrenzenden surfaces becomes, so the surfaces, which are relevant to the boundary layer structure and involved in the loss generation in the machine are. The systematic repetition along the steps of Turbomachine as well as the mesh of one or the other multiple fluid removal / supply schemes is the cause of Achieving a greatly increased aerodynamic resilience all blade rows of the turbomachine (rotors and stators).

Depending on the variant and embodiment of the invention is an increase the load capacity of the fluid flow machine around the Factor 1.5 to 2.5 allows. For a given pressure ratio The flow machine can be maintained while maintaining or improve the efficiency of up to 2% the number the built-in parts by about 50% compared to a conventional Lower built flow working machine. This is a Cost reduction by around 20% achievable.

When using the solution according to the invention in the compressor of a Aircraft engine of, for example, 25,000 pounds of thrust a reduction in specific fuel consumption up to 1%.

It is inventively a novel and highly effective way shown, the load and performance values of Significantly increase flow machines. Specific Forms of turbomachinery with an integrated Fluid circulation system has been detailed, but is the invention is not limited to the embodiments shown. Rather, arise within the scope of the invention varied Ability to modify and modify.

LIST OF REFERENCE NUMBERS

1

rotor

2

stator

3

auxiliary pump

4

management

5

throttle member

6

discharge chamber

7

supply chamber

8th

spindle

Claims (9)

Turbomachine with at least one rotor row (1) and a free number of stator rows (2), of flowing through a fluid, with at least one blade, the on Schaufelkanalbegrenzenden surfaces a Device for removing fluid from the flow path and means for supplying fluid into the flow path has (bifunctionality), with at least one line (4) for returning the withdrawn fluid to an upstream located position of the flow path and at least one another line (4) for the instructions to be supplied Fluids from a further downstream position of the Flow path. Turbomachine according to claim 1, characterized in that the device for fluid removal is formed on at least one blade of at least one stator or rotor row of blades and at least one line (4) on a device for supplying fluid to at least one blade of a rotor or stator row empties. Turbomachine according to claim 1, characterized in that the device for fluid supply to at least one blade of at least one stator or rotor row of blades is formed and via at least one line (4) by a device for fluid removal at least one blade of a rotor or stator is fed. Turbomachine according to one of claims 1 to 3, characterized in that in the conduit (4) a throttle body (5) is arranged. Fluid working machine according to one of claims 1 to 3, characterized in that the conduit (4) allows a free flow of the fluid. Flow working machine according to one of claims 1 to 3, characterized in that the blade is provided with a device for the variable control of the fluid flow cross-section for removal or supply. Turbomachine according to one of claims 1 to 6, characterized in that the line (4) is provided with a discharge chamber (6) for the collection of withdrawn amounts of fluid from individual blades. Turbomachine according to one of claims 1 to 6, characterized in that the line (4) for collecting quantities of fluid to be supplied to individual blades is provided with a supply chamber (7). Turbomachine according to claim 1, characterized in that a fluid supply and fluid discharge channel leading out of the flow path to the housing or the hub is provided on a rotatable stator blade within the rotary spindle to form a bifunctionality.

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