DE102004030449A1 - Compressing device e.g. turbocompressor part, for compressing e.g. air flow, has adjusting pinions acting on guiding units to modify rotation angle of fluid flow, where pinions and units carry out modification of passage section surface - Google Patents

Abstract

The device has guiding units (120-1-120-4) placed inside a flow channel (110) to guide fluid flow. Adjusting pinions (132, 134-1-134-4, 136-1a, 136-1b) act on the guiding units to modify an angle of rotation of the fluid flow. The pinions and the guiding units are made in a manner that they carry out local modification of a surface of passage section crossed by the fluid in the channel, by cooperating in an appropriate manner. Independent claims are also included for the following: (A) a method of controlling a compressing device (B) data medium including a computer program with program codes for a compressing device.

Description

The The invention relates to a compressor device for compacting a flowing Medium, especially air. About that In addition, the invention relates to a method for operating the compressor device and a corresponding computer program.

in the State of the art are such compressor devices, in particular as parts of turbochargers, known, which for charging, that is, for pre-compression of fresh air for an internal combustion engine, serve. The introduction of the pre-compressed fresh air in the combustion chambers of the internal combustion engine allows a power increase of the internal combustion engine. Especially in turbocharged racing engines, it is common upstream of the compressor device to provide a turbo choke in the fresh air duct, which in phases Negative load dynamics, for example when removing the gas from full load for the purpose of changing gear, by means of suitable control a slowed down Speed drop of the turbocharger causes. Slowed down by this Speed drop succeeds after a temporary gas removal spontaneous Rebuilding the boost pressure and consequently a faster Availability from elevated Power of the internal combustion engine.

Farther are from the prior art in particular radial compressor with variable Vorleitdrall known. Such radial compressor have in her flow channel Guiding elements for guiding or guiding a flowing medium on, these guide elements by means of an adjustment are twistable. By a suitable twisting of these guide elements a variation of the helix angle of the flowing medium is possible; this allows advantageously a displacement of the characteristic diagram of the compressor device; more accurate said, possible it is an extension of (left) surge limit and (right) stop limit of the compressor map.

outgoing From this prior art, it is the object of the invention, a Compressor device and a method and computer program for their To provide operation, which has the advantages of a reduced Speed loss with negative load dynamics and a shift of the compressor map combined with each other.

These The object is solved by the subject matter of patent claim 1. More accurate said, the object is achieved by a compacting device for compacting a streaming Solved medium, which includes: a flow channel, in which the medium flows; at least one guide element within the flow channel for conducting or To lead of the streaming medium; an adjusting device for acting on the guide element in order change the helix angle of the flowing Medium and which is characterized in that the adjusting device and the guide element are further formed by suitable Collaborate a local change to realize a flow cross-sectional area, through which the medium flows within the flow channel.

Advantages of invention

The claimed compressor device advantageously allows a Adjusting the guide element in the flow channel so that on the one hand a change the twist angle and on the other hand also a change the flow cross-sectional area, through which the medium flows within the flow channel, is possible. Both effects can in principle be realized consecutively or simultaneously. The change of the Helix angle of the flowing Medium allows an advantageous displacement of the characteristic diagram of the compressor device, the compressor map, for example, the pressure ratio, the is called the Pressure upstream based on the pressure downstream the compressor device, plotted against the volume flow, represents. In particular, allows the change of the helix angle is an extension of the left and the right boundary, the is called the surge limit and the stuffing limit of this compressor field. In contrast, the claimed allows change the flow cross-sectional area advantageously a slowed down speed drop with negative load dynamics and from it as a result, the possibility a faster rebuilding of the boost pressure and the performance of a Internal combustion engine at the beginning of a subsequent charging phase. The Function of change the flow cross-sectional area corresponds the function of the known from the prior art turbo choke upstream the compressor device. This turbo choke and the associated material and installation costs can Therefore saved when using the compressor device according to the invention become.

The in the compressor device according to the invention used guide elements are preferably similar to throttle valves and are in the flow channel rotatably mounted. Depending on control or setting the guide elements cause the said change in the helix angle and / or the flow cross-sectional area.

advantageous Embodiments of the guide elements and an adjusting device for the Control are the subject of the device subclaims.

The The object of the invention is further achieved by a method for operating said compressor device and by a corresponding computer program solved. The advantages of these solutions correspond in principle the advantages mentioned above with respect to the compactor device.

Especially Advantageously, the compressor device according to the invention for Control and / or regulation of the boost pressure of an internal combustion engine used. However, it is between two modes of operation of the internal combustion engine to distinguish. In a first operating mode of the internal combustion engine, which is characterized by a negative load dynamics and meantime a bypass valve of the internal combustion engine is substantially permanent open is, the boost pressure according to the inventive method in accordance with a predetermined time reference charge pressure curve reduced by acting on the vanes that they realize a throttle effect in the form of a reduction of the flow cross-sectional area. In contrast, the guide elements are in an operating mode of the internal combustion engine, in which a charge, that is a pre-compression of the fresh air for the internal combustion engine takes place, so controlled that in the flowing medium a desired angle of twist established. While This second operating mode is a control or regulation of the Boost pressure primarily over one Bypass valve of the internal combustion engine. Only in addition to it will also over the described change of the helix angle acted on the boost pressure. This support of Boost pressure control through the change the twist angle causes an overall improved performance the internal combustion engine, which in particular in an improved efficiency and above In addition, in an extension of the pump and Stopfgrenze in the map of Compressor device affects.

advantageous Methods for determining the optimal helix angle during the second operating mode are the subject of method claims.

drawings

Of the Description are attached to a total of six figures, wherein

1 a compressor device according to the invention installed in a fresh air circuit of an internal combustion engine;

2 the structure of the compressor device according to the invention with a first position of the guide elements;

3 the structure of the compressor device according to the invention with a second position of the guide elements;

4 the structure of the compressor device according to the invention with a third position of the guide elements;

5 the inventive method for operating the compressor device during operation of the internal combustion engine with negative load dynamics;

6 the inventive method for operating the compressor device during a charging operation of the internal combustion engine; and

7 a map of the compressor device illustrated.

description the embodiments

1 shows an internal combustion engine 300 with connected fresh air supply 50a . 50b . 50c and connected exhaust system 150 , Between the exhaust system 150 and the fresh air supply is an exhaust gas turbocharger 200 connected. The turbocharger 200 is used to control or regulation of the boost pressure, that is to control the size of the pressure with which the internal combustion engine supplied fresh air is pre-compressed. This pressure can be controlled by the speed of the turbocharger or its turbine 200a control or regulate. The speed of the turbine 200a and thus the boost pressure are traditionally via a bypass valve 600 in the exhaust duct 150 controlled by using the size of the turbine 200a driving exhaust gas flow rate is controlled.

The compressor device 100 sits in the fresh air supply and serves to compress the fresh air supplied to the internal combustion engine as a flowing medium. When the fresh air supply is between an area upstream 50a and areas downstream 50b . 50c based on the position of the compressor device 100 distinguished. The fresh air enters, as indicated by the arrows in the area of the fresh air supply 1 indicated, first coming from the right by an air mass meter 400 in the area 50a the fresh air supply upstream of the compressor device 100 one. It is then removed from the compressor device 100 condensed and over the areas 50b and 50c which through a motor choke 500 coupled together, in a compressed form the combustion chambers of the internal combustion engine 300 fed.

2 shows an embodiment of the compressor device according to the invention 100 , The compressor device 100 essentially comprises a flow channel 110 who in 2 is shown in cross section. Stationary to the wall of the flow channel is a holder 140 preferably in the form of an intercept. The holder 140 or the intercept are preferably designed streamlined at its upstream end in the form of a spinner (not shown here). In the holder 140 and the wall of the flow channel 110 are mutually associated bearing elements 136-1a , -1b, -2a, -2b, -3a, -3b, -4a, and -4b, each pair defining a fixed axis of rotation DR-1, DR-2, DR-3, and DR-4.

In each case two of the bearing elements 136-1a ...- 4b is each a guiding element 120-1 ...- 4 rotatably mounted about the respective axis of rotation DR-1 ...- 4. 2 shows the guide elements 120-1 ...- 4 only in their profile view in the form of thick, black lines. The flat design guide elements extend in 1 perpendicular to the plane of the drawing; the flow channel is open at this position of the guide elements for the medium flowing through the maximum. In other words, this means that a flow cross-sectional area through which the medium within the flow channel 110 flows in 2 is maximum; the flow cross-sectional area consists of the sum of the four partial areas Sq-1...

For adjustment of the guide elements 120-1 ...- 4, an adjustment is provided. This adjusting device comprises in which in the 2 . 3 and 4 shown embodiment, a first adjusting 132 , which faces the wall of the flow channel 110 is rotatably mounted. Furthermore, the adjusting device comprises in the embodiment according to 2 four second adjusting wheels 134-1 ...- 4th Each of these second adjusting wheels serves to control or adjust a guide element assigned to it individually 120-1 ...- 4th The second adjusting elements are each arranged axially relative to the stationary rotary axes DR-1... 4 and with the guide elements assigned to them 120-1 ...- 4 rotatably connected. Each of the in 2 shown adjusting wheels 134-1 ...- 4 is with the first adjusting wheel 132 rotationally coupled. A rotation of the first adjusting wheel 132 therefore causes a synchronous or in-phase change in the positioning of all four vanes 120-1 ...- 4th The setting of a desired position of the guide elements 120-1 ...- 4 with respect to the flowing medium by suitable rotation of the first adjusting wheel 132 is preferably carried out by an electric drive device 150 , for example a servomotor.

In the 3 and 4 is the same compressor device 100 presented as above with reference to 2 has been described in detail. In contrast to the representation in 2 are in the 3 and 4 the guiding elements 120-1 ...- 4 but shown in other positions. So illustrated 3 a position of the guide elements, the partial closure of the flow channel or a significant reduction in the flow cross-sectional area with respect to the in 2 means shown cross-sectional area. Also in 3 is the total flow cross-sectional area through which the medium flows within the flow channel, formed by the sum of the partial areas Sq-1 ...- 4; however, this sum is much smaller than the sum in 2 ,

In 4 this sum is reduced to a minimum. Each of the sub-areas Sq-1 ...- 4 is in each case only by a thin gap between the now compared to in 2 shown rotated by 90 ° guide elements 120-1 ...- 4 formed. These columns are in 4 indicated by thick, black lines. The flow channel 110 is therefore at the in 4 shown positioning of the guide elements 120-1 ...- 4 except for the mentioned column completely closed.

In 4 is an example of the planar design of the guide elements 120-1 ...- 4 recognizable. In a flow channel with a circular cross section, a segmental design of the guide elements is recommended, as in 4 shown. The guiding elements, in 4 four pieces, are preferably mounted distributed symmetrically over the cross section of the flow channel; they then each cover a segment angle of substantially 360 ° / number of guide elements. In the 2 to 4 this segment angle is 90 ° in each case. This segmental design of the guide elements is particularly clear in 4 to recognize. The 3 and 2 each projected areas of these segment-shaped guide elements with a rotation of the guide elements by about 45 ° in 3 , respectively 90 ° in 2 , opposite to the position in 4 ,

Hereinafter, a method for operating the compressor device according to the invention 100 described in more detail. As already mentioned in the introduction, the compressor device 100 Preferably, for controlling or regulating the boost pressure LD in the internal combustion engine 300 used. However, it is between a first operating mode in which the internal combustion engine 300 is operated with a negative load dynamics, and a second mode of operation in which a permanent load Charging, that is, a continuous pre-compression of the internal combustion engine supplied fresh air is to be distinguished.

The first operating mode denotes a transient state in which the internal combustion engine transitions from a state of charging to a coasting mode. Such a condition arises, for example, due to the removal of gas during a previous full-load operation. The bypass valve 600 is substantially permanently fully open during this first mode of operation; That is, there is no regulation of the boost pressure with the help of the bypass valve instead. Instead, a control of the boost pressure LD according to the present invention for suitable control of the guide elements takes place 120-1 ...- 4th

A corresponding regulation is in 5 exemplified. It can be seen there that the charge pressure LD by means of a boost pressure sensor 510 recorded and in a comparator device 520 , For example, a subtraction device is compared with a target boost pressure SLD. This target boost pressure SLD is time-dependent in the first operating mode; in particular, it describes the time decrease of the charge pressure, starting from a high charge pressure value during a charge phase up to a boost pressure, preferably slightly above the atmospheric pressure in the overrun phase at the end of the first operating mode. One by the comparator 520 formed control deviation e is input to a regulator device 530 , which is a manipulated variable for the drive device 150 for driving, or setting, a correspondingly suitable position of the guide elements 120-1 ...- 4 serves. The control device 530 In the simplest case, it can be a P-controller which corrects the angle of attack of the guide elements in proportion to the control deviation e. A pilot control in the form of an angle specification as a function of the air mass flow rate could be the regulator device 530 effectively support.

By keeping the charge pressure LD in transition to overrun slightly above atmospheric pressure, when using the compressor device 100 in a turbocharger prevents undesirable lube oil from the storage of the turbocharger in the downstream fresh air supply 50b is sucked. The regulator device 530 generates at its output a manipulated variable for controlling the drive device 150 or for setting a desired position of the guide elements 120-1 ...- 4th The guiding elements 120-1 ...- 4 are then during the first operating mode, as in the

3 and 4 shown, adjusted so that the flow channel is almost completely closed; this essentially takes place in parallel with a closing of the engine throttle 500 , By largely closing the fresh air supply arises upstream of the compressor device 100 a negative pressure. Due to this negative pressure, the volume flow of the fresh gas initially remains constant, but its mass flow drops sharply in accordance with the load decrease. This reduces the power consumption of the compressor device 100 , whereby the speed of the exhaust gas turbocharger 200 , fed by the kinetic energy from its own inertia, largely free of pumping and slows down compared to a known in the art air circulation system. The slowed down speed of the turbocharger 200 favors a later spontaneous rebuild the boost pressure LD, since then the starting speed of the exhaust gas turbocharger after a short overrun phase is higher than without a corresponding inventive control of the boost pressure on the setting of the vanes. Instead of in 5 shown and just described control can be controlled according to a predetermined Sollladedruckverlauf also during the first operating mode, the boost pressure.

During the above-mentioned second operating mode of the internal combustion engine, that is, during a charging phase, the control of the boost pressure is basically via the bypass valve 600 as above with reference to 1 described. According to the invention, however, it is proposed that this control of the boost pressure by additionally taking appropriate action on the conductive agent 120-1 ...- 4 of the compaction device 100 to support. In contrast to the first operating mode, the action on the guide elements does not take place in such a way that the latter has the flow channel 110 essentially close, but instead this remains at least largely open. However, then about the guiding elements 120-1 ... 4 a desired helix angle of the through the compressor device 100 flowing medium, that is the fresh air set. The optimum for each operating point twist angle, for example, by evaluating the respective current air mass flow LM and a respective current pressure ratio DV upstream to the downstream of the compressor device 100 with the help of a characteristic field KD according to 7 determined, wherein in the map KD the pressure ratio DV is plotted against a volume flow V. The thus determined optimum helix angle is then in a corresponding manipulated variable for the drive device 150 for adjusting the guide elements 120-1 ...- 4 of the compressor device 100 converted and fed this. The set in this way swirl angle of the fresh air supports the above-mentioned regulation of the exhaust gas turbocharger 200 generated boost pressure. The setting of the optimum helix angle leads in particular to a desired displacement or change the map of the compressor device 100 ; more precisely, to an extension of the surge limit P of the map to the left or to smaller volume flows (see 7 ). In this case, I identifies the effective compressor map at maximum helix angle, while II indicates the compressor map without swirl. The twist angle can max. 60-70 °, ie the incoming air is flowing through the device max. about 60-70 ° counter to the direction of rotation of the compressor wheel deflected, so that a rotation of the inflowing air column axially to and against the compressor wheel is formed.

The inventive method is preferably in the form of a computer program for a control unit for controlling the turbocharger, or the drive device 150 , realized. This computer program may optionally be stored together with other computer programs for controlling and / or regulating the internal combustion engine on a computer-readable data carrier. The data carrier can be a floppy disk, a compact disc (CD), a so-called flash memory or the like. The computer program stored on the data carrier can then be transferred or sold as a product to a customer. As an alternative to a transfer of the computer program by means of a data carrier, the computer program can also be transmitted to the customer without the aid of the data carrier via an electronic communications network, in particular via a client-server network such as the Internet.

Claims (14)

Compactor device ( 100 ), in particular as part of a turbocharger ( 200 ), for compressing a flowing medium, in particular air, comprising: a flow channel ( 110 ) in which the medium flows; at least one guiding element ( 120-1 ...- 4) within the flow channel ( 110 ) for conducting the flowing medium; and an adjusting device ( 132 . 134 . 136 ) for acting on the guide element ( 120-1 ...- 4) for the purpose of changing the angle of twist of the flowing medium; characterized in that the adjusting device ( 132 . 134 . 136 ) and the guiding element ( 120-1 ...- 4) are further designed to realize a local variation of a flow cross-sectional area (Sq-1... 4) by suitable cooperation, through which the medium within the flow channel (FIG. 110 ) flows. Contraption ( 100 ) according to claim 1, characterized in that the device comprises: one in the flow channel ( 110 ) fixedly positioned holder ( 140 ), preferably in the form of an intercept; and at least one bearing element (136-ia, 136-ib with i = 1 ... 4) in the holder ( 140 ) and a wall of the flow channel ( 110 ), wherein the two bearing elements (136-ia, 136-ib with i = 1 ... 4) are associated with each other and together define a fixed axis of rotation (DR-1 ...- 4), and wherein the guide element ( 120-1 ...- 4) between the wall and the bracket ( 140 ) is rotatably mounted in the bearing elements about the rotational axis (DR-1 ...- 4). Contraption ( 100 ) according to claim 2, characterized in that the adjusting device comprises: a with respect to the flow channel ( 110 ) rotatably mounted first adjusting wheel ( 132 ); and at least one axially to the stationary axis of rotation (DR-1 ...- 4) arranged and with the guide element ( 120-1 ...- 4) rotatably connected second Verstellrad ( 134-1 ...- 4), which with the first adjustment wheel ( 132 ) is rotationally coupled. Contraption ( 100 ) according to claim 3, characterized by a drive device ( 150 ), preferably a servomotor, for setting a desired position of the guide element ( 120-1 ...- 4) with respect to the flowing medium by suitable rotation of the first Verstellrades ( 132 ). Contraption ( 100 ) according to one of the preceding claims, characterized in that the device ( 100 ) a plurality of guide elements ( 120-1 ...- 4), which when stored in a portion of the flow channel ( 110 ) are each formed with a circular cross-section segment-shaped. Apparatus according to claim 5, characterized in that the guide elements ( 120-1 ...- 4) symmetrically over the cross-section of the flow channel ( 110 ) are distributed and each cover a segment angle of substantially 360 ° / number of vanes. Method for operating a compressor device ( 100 ), in particular a turbocharger, for compressing one through a flow channel ( 110 ) of the compressor device ( 100 ) flowing medium, comprising the steps: acting on at least one guide element ( 120-1 ...- 4) in the flow channel ( 110 ), in particular for influencing the twist angle of the flowing medium; characterized in that with the action on the guide element ( 120-1 ...- 4) also a local change of a flow cross-sectional area (Sq-1 ...- 4) is feasible, through which the medium within the flow channel ( 110 ) flows. Method according to claim 7, characterized in that the compressor device ( 100 ) in an internal combustion engine ( 300 ) is used to control or regulate the boost pressure (LD). A method according to claim 8, characterized in that in an operating mode of the internal combustion engine ( 300 ), which is characterized by a negative load dynamics and meanwhile a bypass valve ( 600 ) of the internal combustion engine ( 300 ) is substantially permanently opened, the charge pressure (LD) is reduced in accordance with a predetermined time reference charge pressure progression (SLD) by acting on the guide element (16) by suitable action. 120-1 ...- 4) a throttle effect in the form of a reduction of the flow cross-sectional area is realized. A method according to claim 8, characterized in that in an operating mode of the internal combustion engine, in which a charge takes place, then taking place control or regulation of the boost pressure (LD) via a bypass valve ( 600 ) of the internal combustion engine ( 300 ) by an additional suitable action on the guide element ( 120-1 ...- 4) the compressor device ( 100 ) is supported. A method according to claim 10, characterized in that by the action on the guide elements ( 120-1 ...- 4) is set for each operating point of the internal combustion engine optimum helix angle of the flowing medium. A method according to claim 11, characterized in that the respective optimum helix angle taking into account the air mass flow and the pressure ratio upstream to the downstream of the compressor device ( 100 ) or vice versa, preferably determined from a map (KD). Computer program with program code for a compressor device characterized in that the program code is designed for execution The method according to any one of claims 7 to 12. disk characterized by the computer program of claim 13.