DE102012208716A1 - Device for modification of gas flow i.e. effluent stream, of combustion engine of sports vehicle, has throttle element arranged rotatable over rotational axis and delegated to main flow axis of gas stream placed in gas guide portion - Google Patents

Abstract

The device has a throttle element (16) arranged rotatable over a rotational axis (D) in one of gas stream (G) made to flow through a gas guide section (12). The rotational axis of the throttle element is arranged parallel or vertical to a main flow axis (S) of the gas stream. The throttle element is delegated to the main flow axis of the gas stream placed in the gas guide portion. The gas guide section is formed by a pipe section. A projection (18) receives a part of the throttle element. The throttle element is actively driven to a rotational motion (R) by a drive unit. Independent claims are also included for the following: (1) a testing apparatus (2) a method for modification of effluent stream of a combustion engine.

Description

The present invention relates to a device for modifying a sound pattern generated by a gas flow, in particular exhaust gas flow of an internal combustion engine.

In many fields of technology, there is a need to influence the sound patterns generated by the operation of a device. In motor vehicles, for example, sound is generated by the engine and by the exhaust gas emitted by it. In order to meet increasingly stringent standards, it may be necessary in some cases to reduce the amount of sound generated - in total or in certain frequency ranges. But it may also be desirable to consciously generate a specific sound pattern. For example, engine optimization techniques have made significant progress in terms of fuel economy and emissions. However, such optimization measures often also suffer from the sound produced by the engine. It is therefore tried by a "sound design" to produce the sound expected by the customer, for example, a particularly sporty vehicle sound.

In order to influence the sound pattern of a motor vehicle, for example, a loudspeaker may be provided. Alternatively or additionally, the exhaust gas flow can be used to generate the desired sound pattern.

It is an object of the present invention to provide a device which makes it possible in a simple way to influence the sound pattern generated by a gas flow in the desired manner.

For this purpose, at least one rotatable about an axis of rotation throttle element is provided, which is arranged in a flowed through by the gas flow gas guide portion. The axis of rotation of the throttle element is arranged transversely, in particular perpendicular, to the main flow axis of the gas flow.

According to the throttle element is arranged offset to the main flow axis of the gas flow in the gas guide section.

In other words, the throttle element, which may be a throttle valve, for example, is not arranged centrally in the gas flow. Due to the relative to the gas flow flowing into the gas flow section arrangement of the throttle element "immersed" this example, only partially in the gas flow.

It is understood that the gas routing section may contain other components that contribute to the desired modification of the sound pattern. It is also possible to integrate the device described above in a silencer.

The object outlined above is also achieved by a device which has at least one throttle element which can be rotated about a rotational axis and which is arranged in a gas guiding section through which the gas stream flows. According to the invention, the throttle element is displaceable parallel or transversely, in particular vertically, relative to the main flow axis of the gas flow.

The displaceability of the throttle element provides an additional possibility for influencing the gas flow and thus ultimately the sound pattern generated by the gas flow. The gas flow can then be influenced on the one hand by the rotational position of the throttle element or by its rotational speed and on the other hand by the displacement of the throttle element relative to the flow main axis of the gas flow.

In particular, the throttle element is displaceable in the axial direction of the axis of rotation and / or transversely, in particular perpendicular to the axis of rotation. The axis of rotation of the throttle element may be arranged parallel or transversely, in particular perpendicular to the main flow axis.

According to a development of the device described above, the axis of rotation of the throttle element is arranged offset from the main flow axis of the gas flow. In other words, the rotation axis does not intersect the main flow axis.

The throttle element may be arranged such that even in the case of a closed position of the throttle element, a portion of the cross section of the gas guide portion perpendicular to the flow major axis of the gas flow of at least a portion of the gas flow is freely flowed through.

It may be provided that the axis of rotation of the throttle element is arranged transversely, in particular perpendicular, to the main flow axis of the gas flow and only partially protrudes into the gas stream, wherein the axis of rotation protrudes in particular at least about 75% of their total length in the gas stream, ie the axis of rotation does not traverse the complete cross section of the housing. It is also possible that, although an axis which is fixedly connected to the throttle element or on which the throttle element is rotatably mounted, the gas passage section completely traverses that Throttle element itself, however, is arranged offset in relation to the flow main axis of the gas flow.

In particular, the throttle element is completely rotatable about its axis of rotation. That Rotations through 360 ° and more are possible in this embodiment, for example, to be able to drive the throttle element to a rotational movement with a constant or variable speed.

According to a structurally simple embodiment of the device, the gas guide section is formed by a pipe section. Such a pipe section can be easily integrated into known systems for guiding a gas flow, in particular in exhaust systems. The pipe section may have a bulge, wherein the bulge receives at least a portion of the throttle element.

The throttle element can be driven by a drive unit, for example by an electric motor, active to a rotational movement. Thus, a rotational position of the throttle element or its rotational movement can be adjusted as needed to produce the desired sound pattern.

The drive unit is in particular configured such that the rotational position or the rotational movement of the throttle element can be controlled as a function of at least one of the gas flow measured upstream and / or downstream of the device. For this purpose, an external or internal control device may be provided, e.g. the speed of the throttle element varies as a function of the pressure fluctuations in the gas flow. Alternatively or additionally, the drive unit may be configured such that the rotational position or the rotational movement of the throttle element in dependence on at least one state parameter of an engine - that is motor parameter dependent - controllable, the exhaust gases form the gas stream.

According to one embodiment, an actuation device is provided, with which the throttle element is displaceable, wherein the actuation device is preferably configured such that the displacement movement of the throttle element is controllable depending on at least one upstream and / or downstream of the device measured state parameter of the gas flow and / or engine parameter dependent. This condition parameter / motor parameter can - but need not - be the same as that which is used to control the rotational position or the rotational movement of the throttle element.

In principle, it is possible to provide at least two throttle elements which are arranged offset in the flow direction of the gas flow at the same height and / or in a direction perpendicular to the main flow axis of the gas flow in order to modify the sound pattern in the desired manner. The axes of rotation of the throttle elements may for example be arranged offset from each other in parallel or aligned with each other. In principle, the throttle elements can be controlled in such a way that they perform synchronous movements. But it is also possible to provide a control that allows different rotational positions or rotational movements of the throttle elements. For example, the throttle elements may be driven at different speeds to specifically affect different frequency ranges of the pressure fluctuations in the gas flow.

According to one embodiment of the device, this has a bypass line, by means of which a part of the gas flow, bypassing the throttle element through the device is feasible. The bypass line can have an element for the static or variable influencing of the cross section of the bypass line, the element in particular comprising a tapered tube section, for example for generating the Venturi effect, a static aperture and / or an adjustable throttle.

According to a further embodiment, the throttle element is formed symmetrically with respect to its axis of rotation. In certain applications, however, an asymmetric configuration of the throttle element may be provided.

In many cases, a two-lobe design of the throttle element leads to a minimization of the backpressure generated by the throttle element. In this context, a two-winged embodiment may, for example, be understood to mean a construction in which the throttle element has two wings which are offset by 180 ° with respect to the axis of rotation of the throttle element. For example, the throttle element is a substantially flat disc, so that the cross section of the throttle element is minimal in a fully open position.

According to one embodiment of the throttle element, at least one of the wings, in particular both wings, a wing portion which is disposed at an end remote from the axis of rotation of the wing and which is inclined relative to a plane defined by the rest of the wing. In other words, such a throttle element comprises at least one wing, which has two segments that are tilted relative to each other. By choosing suitable ratios of the areas of the two segments and the adjustment of the inclination between the two segments, the Throttle be adapted to the respective requirements.

In principle, it is possible to design the wings in such a way that, in a closed position of the throttle element, they have a substantially rectangular contour in the direction of view of the gas flow. In particular, in embodiments of the device comprising two staggered throttle elements, this results in a flow-dynamically optimized free cross-section in the interior of the gas guide section so even with a closed position of the throttle elements. In particular, at least one of the wings has a recess at the edge, which is in particular semicircular or oval.

The invention also relates to a test device that can be used in particular for testing components of exhaust systems. Such a testing device has a gas flow generating unit for generating a gas flow with specific pressure fluctuations. The generated gas stream can be supplied to the components to be tested in order to be able to test them under realistic conditions. In order to cope with said specific pressure fluctuations - i. To generate the temporal variation of the pressure conditions in the gas flow, the gas flow generating unit comprises a device according to at least one of the embodiments described above.

The invention further relates to a method for modifying a sound pattern generated by a gas flow, in particular exhaust gas flow of an internal combustion engine, in particular for generating a desired engine sound, wherein a device, in particular according to at least one of the embodiments described above, is provided which at least one about an axis of rotation having rotatable throttle element, which is arranged in a gas flow through the flow passage portion. The axis of rotation of the throttle element is arranged transversely, in particular perpendicular, to the flow direction of the gas flow and the throttle element is arranged offset to the main flow axis of the gas flow. The rotational position or the rotational movement of the throttle element is controlled as a function of at least one of the gas flow measured upstream and / or downstream of the device and / or engine parameter dependent.

In an alternative method, the device - which is designed in particular according to at least one of the embodiments described above - at least one rotatable about an axis of rotation throttle element, which is arranged in a flowed through by the gas flow gas guide section. The throttle element is parallel or transverse, in particular perpendicular, displaceable to the flow main axis of the gas flow. The throttle element is displaced as a function of at least one state parameter of the gas flow measured upstream and / or downstream of the device and / or engine parameter-dependent.

The rotational movement of the throttle element can be controlled as a function of this state parameter or of another state parameter of the gas flow and / or engine parameter-dependent, as in the first-described method.

Further embodiments of the invention are indicated in the description, the claims and the attached drawings.

Hereinafter, the present invention will be explained purely by way of example with reference to advantageous embodiments with reference to the accompanying drawings. Show it:

1 an embodiment of the invention in a cross section,

2 a view of the embodiment of the 1 in the flow direction of the gas stream,

3A a schematic representation of a so-called "axial rotor",

3B a schematic representation of a staggered "axial rotor",

4 a cross section through a further embodiment of the invention,

5 a cross section through a further embodiment of the invention,

6 an embodiment of the invention with a bypass line,

7A . 7B respectively. 8A . 8B Further embodiments of the invention in different views and

9A . 9B . 10 and 11 various embodiments of the throttle element.

1 shows a sound pattern modification device 10a with a gas routing section 12 that with pipes 14a . 14b an exhaust system of a motor vehicle is connected. A gas stream G flowing through the exhaust system generates a sound pattern which it has to modify as part of a "sound design". For this purpose, a throttle flap arranged rotatably about a rotation axis D is provided 16 intended. The axis of rotation D is perpendicular to a flow major axis S of the gas flow G. The throttle 16 is offset from the main flow axis S, so that the rotation axis D and the main flow axis S do not intersect. This has the consequence that regardless of a rotational position of the throttle 16 always referred to as a "radial offset" R cross-sectional area of the gas guide section 12 can be passed through unhindered by a portion of the gas stream G.

In order to change the sound pattern of the gas flow G caused, for example, by pressure fluctuations, the rotational position of the throttle flap is changed 16 adapted as needed. For example, the throttle will 16 in a rotary motion r about the axis of rotation D, whose frequency is adjusted so that the pressure fluctuations are modified in a suitable manner, for example, to simulate a particularly sporty engine sound. For example, in the flow direction in front of and / or behind the device 10a Sensors (not shown) are arranged, which detect the pressure fluctuations in the gas flow G and pass the acquired data to a control device (not shown), which in turn suitably the rotational position or the rotational movement r of the throttle valve 16 controls.

The device 10a is thus configured such that due to the radial offset R no complete closure of the cross section of the gas guide section 12 and so that no complete interruption of the gas flow G are effected.

The gas routing section 12 has a bulge 18 on, relative to the flow major axis S staggered throttle element 16 at least partially. Through the bulge 18 is also causing the in 1 upper part of the throttle 16 is more strongly flowed by the gas stream G than the lower part of the throttle valve 16 , With a rotation r of the throttle valve 16 clockwise this means less forces on the throttle 16 Act. In other words, the asymmetric flow is the throttle 16 advantageous because the moving against the flow direction of the gas flow G part of the throttle valve 16 less strongly flowed directly as the moving in the flow direction part of the rotating throttle 16 , Ultimately, this causes the device 10a operate more efficiently and that they generate less backpressure and / or turbulence.

It is understood that not only the rotational position or the rotational movement r of the throttle valve 16 but also the position of the rotation axis D relative to the main flow axis S and thus ultimately the radial offset R has a significant influence on the gas flow G and thus on the sound pattern produced. The design of the throttle valve 16 itself influences the sound pattern. Basically, any configuration of the throttle valve 16 conceivable in order to be able to cope with the respective requirements. Notwithstanding the illustrated two-lobe, relative to the axis of rotation D symmetrical design of the throttle 16 this may be constructed asymmetrically and / or have more than two wings, which are evenly or non-uniformly distributed about the axis of rotation D. Also the shape of the throttle 16 in a plane perpendicular to the image plane of 1 can be chosen arbitrarily. The throttle 16 may be circular, oval, angular or irregularly shaped. It may also have recesses and / or openings. It is also possible that the throttle 16 has obliquely placed segments relative to the main flow axis S. Advantageous embodiments of the throttle valve 16 be with reference to the 9A . 9B . 10 and 11 described.

2 shows a simplified representation of the device 10a seen in the direction of the main flow axis S. As a result, the substantially circular configuration of the throttle valve 16 recognizable, however - as indicated above - can be modified as needed. The view of 2 further shows that the axis of rotation D is arranged offset relative to the main flow axis S downwards, which ultimately results in the axes S, D do not intersect. In addition, the designated as radial offset R area of the cross section of the gas guide section 12 to see who also in the 2 shown closed position of the throttle 16 not closed.

3A shows a sound pattern modification device 10b having an axial rotor. The throttle 16 the device 10b has an axis of rotation D, which is arranged coaxially to the flow major axis S. In 3B is a device 10b ' to see, where the axis of rotation D of the throttle 16 is offset in parallel in the radial direction with respect to the axis S, so that here also a rotation angle-dependent blocking of the cross section of the gas guide section 12 is generated, which leads to the sound pattern modification. It is understood that the throttle 16 deviating from the illustrated embodiment can basically be arbitrarily shaped.

4 shows a sound pattern modification device 10c which also has a throttle valve arranged offset from the main flow axis S. 16 having. The axis of rotation D of the throttle 16 traverses the gas routing section 12 not completely, leaving the throttle 16 only partially immersed in the gas stream G. This leads to a so-called "axial offset" A. Analogous to that based on the 1 and 2 described radial offset R causes the axial offset A that a part of the cross section of the gas guide section 12 the device 10c regardless of the rotational position of the throttle 16 is freely flowed through.

In the device 10c are the axis of rotation D of the throttle 16 and the main flow axis S in a plane. Deviating from this, however, it can also be provided that the axes D, S do not intersect. In this case, both an axial offset A and a radial offset R are present. The comments on the design of the throttle 16 in connection with the device 10a apply analogously to the device 10c as well as for all other embodiments of the sound modification device according to the invention.

In addition to the above-described axial offset A is in 4 a drive unit 20 shown, the indicated by the arrow r rotation of the throttle valve 16 generated. The drive unit 20 is also capable of the throttle 16 to move in a direction perpendicular to the flow major axis S, as indicated by the arrow a. The ability to generate translational motion along the direction a is optional. However, it offers an additional possibility for influencing the sound pattern generated by the gas flow G.

The translation movement may also be by one of the drive unit 20 separate unit be effected. It can be provided to perform the translational movement as a function of suitable state parameters of the gas flow G. In principle, it makes sense to use the same state parameters that are used to control the rotational movement r, but this is not absolutely necessary.

5 shows a sound pattern modification device 10d which in certain aspects of the acoustic pattern modifying device 10a equivalent. The device 10d has a throttle 16 on, whose axis of rotation D - as in the device 10a - Is arranged offset relative to the main flow axis S, that there is a radial offset R. Unlike the device 10a is the axis of rotation D of the throttle 16 the device 10d but displaceable parallel to the main flow axis S, as by the various positions I, II, III of the throttle 16 is indicated. To the radial offset R in in 5 upper area of the device 10d comes a radial offset R ', which increases from position I to position III. In other words, by a shift of the rotational axis D of the throttle valve 16 an influence on the gas flow G is effected parallel to the main flow axis S. The flow parallel displacement of the axis of rotation D can with the in 4 shown movement of the rotation axis D are combined, if there is a corresponding need.

6 shows a sound pattern modification device 10e in which the throttle 16 not rotatable by 360 °. However, their rotational position can be adjusted as needed. Also, one of the 6 not to be taken axial offset A of the rotation axis D relative to the flow major axis S provided. As can be seen from the above explanations, therefore, is a certain part of the cross section of the gas guide section 12 regardless of the rotational position of the throttle 16 from a part of the gas flow G freely flowed through.

Furthermore, a bypass line 22 provided in 6 not to scale but only schematically shown. Through the bypass line 22 a portion of the gas stream G flows along a bypass axis S '. The bypass line 22 the device 10e has a throttle device 24 on, for example, includes a proportionally adjustable throttle or a static shutter. The bypass line 22 may alternatively or additionally have a taper to the flow behavior of the bypass line 22 flowing through part of the gas flow G in terms of the Venturi effect to influence.

7A shows a sound modifying device 10f , the two throttle valves movable along parallel translational movement directions a perpendicular to the main flow axis S 16 has, which are rotatable about a respective axis of rotation D. The axes of rotation D of the throttle valves 16 are offset in the flow direction of the gas stream G arranged in parallel one behind the other.

In contrast, the axes of rotation D of the throttle valves 16 a sound pattern modification device 10g - please refer 8A - In the flow direction of the gas stream G arranged at the same height. The translational movement directions a arranged perpendicular to the main flow axis S are thus on one axis.

It is understood that a misalignment of the throttle 16 and / or a maximum amplitude of the translation of the throttle valves 16 are chosen so that they do not collide with each other in their respective rotational movements r. Alternatively or additionally, the rotational movements r of the throttle valves 16 synchronized or offset from each other synchronized.

The 7B and 8B each show one to the 2 analogous view of the embodiments according to 7A respectively. 8A ,

From the foregoing, it can be seen that there are a variety of possibilities, such as two or more throttle valves 16 can be combined with each other to modify the sound pattern generated by the gas flow G in the desired manner. Notwithstanding the design of the devices 10f . 10g For example, at least one of the throttle valves 16 Has a parallel to the flow direction of rotation D axis of rotation. On a displacement of one of the throttle valves 16 or both throttle valves 16 of the devices 10f . 10g may be omitted if the desired sound pattern modification can already be achieved by a suitable offset R and / or A and control of the throttle valve movement.

9A shows a throttle 16 in a cross-section perpendicular to the axis of rotation D. The throttle 16 will be formed in practice usually much flatter than in 9a exemplified. It has two substantially planar wings 26 on, which are arranged in a plane and thus symmetrical to the rotation axis D. It is easy to see that in an open position the throttle 16 in which she is relative to the in 9A shown rotated position by 90 °, the inflowing gas flow G only a very small cross-sectional area opposes, so that through the throttle 16 generated back pressure is minimal in this position.

9B shows an embodiment of the throttle valve 16 whose wings 26 with wing sections 26a are each provided opposite the remaining part of the respective wing 26 are arranged inclined. Especially in intermediate positions of the throttle 16 , ie in positions between the maximum open and the maximum closed position of the throttle valve 16 , This embodiment often proves to be advantageous because stalls at the ends of the wings facing away from the axis of rotation D 26 , in particular at the respective time downstream arranged wings 26 to be minimized.

The geometry of the throttle 16 in a plane containing the axis of rotation D can be configured arbitrarily. In many cases, however, a circular geometry proves to be advantageous, especially if only one throttle 16 is provided. In embodiments with two throttle valves 16 , as in the example 7A . 7B . 8A and 8B However, it is shown that often a rectangular contour of the wings 26 the throttle valves 16 flow dynamics is advantageous. A corresponding embodiment is in 10 shown the view of the 8B is comparable. With a substantially same basic structure as in the sound pattern modifying device 10g are the wings 26 the throttle valves 16 but not semi-circular but rectangular. The resulting free cross section - is shown in 10 a maximum closed position of both throttle valves 16 - Is of fluid dynamics simpler geometry than that found when using throttle valves 16 with a circular contour (cf. 8B ).

11 shows a modification of the throttle 16 of the 10 , The throttle valves 16 of the 11 each have a semicircular recess 26b on. At the illustrated maximum closed position of the throttle 16 The result is a free cross-section in the central region around the main flow axis S, which is the flow of gas G less influenced flow dynamic than that of the embodiments of 10 and 8B , Ultimately, this leads to a minimization of an undesirable portion of the throttle valves 16 generated back pressure.

If only one of each wing 26 the throttle valves 16 with a recess 26b is provided, in particular comparatively strong pulsations in the gas stream G can be generated or compensated. In principle it is also possible to use both wings 26 the throttle valves 16 always the same. In this case, the dashed recesses are also 26b ' intended.

The invention has been described above by way of example in connection with the modification of a sound pattern of an exhaust gas flow flowing through an exhaust system. In principle, however, it is also possible to use the device according to the invention for generating pulsations in a constant gas mass flow.

Conventional testing devices for testing durability, structural dynamics, and thermodynamics of exhaust system components include hot gas generators that produce a constant gas mass flow. However, such test devices provide comparatively realistic test conditions, since pressure pulsations occur in such exhaust systems. In order to be able to produce more realistic conditions, combustion engines are therefore often used instead of the hot gas generators, whose exhaust gases are supplied to the components to be tested. However, this procedure is complicated and costly.

With the aid of the device according to the invention, the constant gas mass flow of a conventional hot gas generator can be determined by a suitable geometric configuration of the throttle valve (s). 16 and the gas routing section 12 and by a suitable control of the throttle valve (s) 16 In a simple way, a realistic Druckpulsationsmuster be impressed. In other words, such realistic test conditions can be generated without having to resort to internal combustion engines, which leads to significant cost savings.

LIST OF REFERENCE NUMBERS

10a, 10b, 10b ', 10c, 10d, 10e, 10f, 10g

 Sound pattern modification device

12

Gas guide section

14a, 14b

pipe

16

throttle

18

bulge

20

drive unit

22

bypass line

24

throttling device

26

wing

26a

wing section

26b, 26b '

recess

G G

asstrom

D D

rehachse

S S

trömungshauptachse

S '

In addition to the current axis

R, R '

radial offset

A a

xial offset

r D

rehbewegung

a T

ranslationsbewegungsrichtung

I, II, III

position

Claims (26)

Device for modifying a sound pattern generated by a gas flow (G), in particular exhaust gas flow of an internal combustion engine, in particular for generating a desired engine sound, with at least one throttle element (D) rotatable about an axis of rotation (D) ( 16 ), which in a gas flow passage (G) through which the gas flow ( 12 ) is arranged, wherein the axis of rotation (D) of the throttle element ( 16 ) transversely, in particular perpendicularly, to the main flow axis (S) of the gas flow (G) is arranged, characterized in that the throttle element ( 16 ) to the main flow axis (S) of the gas flow (G) offset in the gas guide section ( 12 ) is seconded. Device for modifying a sound pattern generated by a gas flow (G), in particular exhaust gas flow of an internal combustion engine, in particular for generating a desired engine sound, with at least one throttle element (D) rotatable about an axis of rotation (D) ( 16 ), which in a gas flow passage (G) through which the gas flow ( 12 ), in particular according to claim 1, characterized in that the throttle element ( 16 ) is displaceable parallel or transversely, in particular perpendicularly, relative to the main flow axis (S) of the gas flow (G). Apparatus according to claim 2, characterized in that the axis of rotation (D) of the throttle element ( 16 ) is arranged parallel or transverse, in particular perpendicular, to the main flow axis (S). Device according to at least one of the preceding claims, characterized in that the axis of rotation (D) of the throttle element ( 16 ) is arranged offset to the main flow axis (S) of the gas stream (G). Device according to at least one of the preceding claims, characterized in that the throttle element ( 16 ) is arranged such, even in the case of a closed position of the throttle element ( 16 ) a part of the cross section of the gas guide section ( 12 ) perpendicular to the main flow axis (S) of the gas stream (G) of at least a portion of the gas stream (G) is freely flowed through. Device according to at least one of the preceding claims, characterized in that the axis of rotation (D) of the throttle element ( 16 ) is arranged transversely, in particular perpendicular, to the main flow axis (S) of the gas stream (G) and projects only partially into the gas stream (G), wherein the axis of rotation (D) in particular to at least about 75% of their total length in the gas stream (G) protrudes , Device according to at least one of the preceding claims, characterized in that the throttle element ( 16 ) is completely rotatable about its axis of rotation (D). Device according to at least one of the preceding claims, characterized in that the gas guidance section ( 12 ) is formed by a pipe section. Apparatus according to claim 8, characterized in that the pipe section has a bulge ( 18 ), which at least a part of the throttle element ( 16 ). Device according to at least one of the preceding claims, characterized in that the throttle element ( 16 ) by a drive unit ( 20 ) is actively drivable to a rotary motion (r). Apparatus according to claim 10, characterized in that the drive unit ( 20 ) is configured such that the rotational movement (r) of the throttle element ( 16 ) as a function of at least one state parameter of the measured upstream and / or downstream of the device Gas flow (G) and / or engine parameter dependent controllable. Apparatus according to claim 1 to 11, characterized in that an actuation device ( 20 ) is provided, with which the throttle element ( 16 ) is displaceable, wherein the Aktuierungseinrichtung ( 20 ) is preferably configured such that the displacement movement (a) of the throttle element ( 16 ) as a function of at least one upstream and / or downstream of the device measured state parameter of the gas flow (G) and / or engine parameter dependent controllable. Device according to at least one of the preceding claims, characterized in that at least two throttle elements ( 16 ) are provided, which are arranged in the flow direction of the gas stream (G) at the same height or offset from one another. Device according to at least one of the preceding claims, characterized in that at least two throttle elements ( 16 ) are provided, which are both offset from the main flow axis (S) of the gas stream (G) are arranged and / or relative to the flow major axis (S) of the gas stream (G) are displaceable. Apparatus according to claim 13 or 14, characterized in that the axes of rotation (D) of the throttle elements ( 16 ) are arranged parallel to each other or aligned with each other. Device according to at least one of the preceding claims, characterized in that the device comprises a bypass line ( 22 ), by means of which a part of the gas flow (G), bypassing the throttle element ( 16 ) Is guided by the device. Apparatus according to claim 16, characterized in that the bypass line ( 22 ) an element ( 24 ) for static or variable influencing of the cross section of the bypass line, wherein the element ( 24 ) comprises in particular a tapered pipe section, a static shutter and / or an adjustable throttle. Device according to at least one of the preceding claims, characterized in that the throttle element ( 16 ) is formed symmetrically with respect to its axis of rotation (D). Device according to at least one of the preceding claims, characterized in that the throttle element ( 16 ) two wings ( 26 ), which are arranged offset with respect to the axis of rotation (D) by 180 °. Apparatus according to claim 19, characterized in that at least one of the wings ( 26 ), especially both wings ( 26 ), a wing section ( 26a ), which at one of the rotational axis (D) facing away from the end of the wing ( 26 ) and the relative to one through the rest of the wing ( 26 ) defined plane is inclined. Device according to claim 19 or 20, characterized in that the wings ( 26 ) are configured such that they are in a closed position of the throttle element ( 16 ) in the direction of the gas flow (G) have a rectangular contour. Device according to at least one of claims 19 to 21, characterized in that at least one of the wings ( 26 ) at the edge a recess ( 26b ), which is in particular semicircular.  Test device, in particular for testing components of exhaust systems, comprising a gas flow generating unit for generating a gas flow with specific pressure fluctuations, wherein the gas flow generating unit comprises a device according to at least one of the preceding claims. Method for modifying a sound pattern generated by a gas flow (G), in particular exhaust gas flow of an internal combustion engine, in particular for generating a desired engine sound, wherein a device, in particular according to at least one of the preceding claims, with at least one throttle element (D) rotatable about an axis of rotation (D) 16 ), which in a gas flow passage (G) through which the gas flow ( 12 ), is provided, wherein the axis of rotation (D) of the throttle element ( 16 ) transversely, in particular perpendicular, to the main flow axis (S) of the gas flow (G) is arranged, wherein the throttle element ( 16 ) is arranged offset to the main flow axis (S) of the gas flow (G) and wherein a rotational movement (r) of the throttle element ( 16 ) is controlled as a function of at least one state parameter of the gas flow (G) measured upstream and / or downstream of the device and / or dependent on engine parameters. Method for modifying a sound pattern generated by a gas flow (G), in particular exhaust gas flow of an internal combustion engine, in particular for generating a desired engine sound, wherein a device, in particular according to at least one of claims 2 to 17, with at least one about an axis of rotation (D) rotatable Throttle element ( 16 ), which in a gas flow passage (G) through which the gas flow ( 12 ), is provided, wherein the throttle element ( 16 ) parallel or transversely, in particular vertically, relative to the flow major axis (S) of the gas flow (G) is displaceable, and wherein the throttle element ( 16 ) is shifted depending on at least one of the upstream and / or downstream of the device measured state parameter of the gas flow (G) and / or motor parameter dependent. A method according to claim 25, characterized in that the rotational movement (r) of the throttle element ( 16 ) is controlled as a function of at least one state parameter of the gas flow (G) measured upstream and / or downstream of the device and / or dependent on engine parameters.

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