Enclosure for a vehicle wheel, measuring system with an enclosure and method for measuring emissions

Abstract

The invention relates to an enclosure (10) for a vehicle wheel (2) for collecting emissions emanating from the vehicle wheel (2), which largely encloses the vehicle wheel (2) and a collection chamber (15), comprising an outer cover wall (12) extending radially with respect to a wheel central axis (M) and a circumferential wall (14) adjoining the cover wall (12), extending in the direction of rotation around the wheel central axis (M), and having a width (B) in the axial direction. wherein an opening (18) on the underside is arranged in the circumferential wall (14) through which the vehicle wheel (2) can be in contact with a surface (3), and wherein a collector opening (19) is provided in the circulation wall (14) through which air loaded with emissions can be discharged from the collection chamber (15) or The flow is dissipated. Optimized measuring conditions are obtained by extending the collector opening (19) axially over more than 70% of the width (B), preferably between 80% and 95% of the width (B) of the circumferential wall (14).

Description

[0001] The invention relates to an enclosure for a vehicle wheel for collecting emissions emanating from the vehicle wheel, which largely encloses the vehicle wheel and a collection chamber, comprising an outer cover wall extending radially with respect to a wheel center axis and a circumferential wall adjoining the cover wall, extending in the direction of rotation around the wheel center axis and having a width in the axial direction, wherein an opening is arranged in the circumferential wall on the ground side through which the vehicle wheel can be in contact with a ground, and wherein a collector opening is provided in the circumferential wall through which air laden with emissions can be discharged from the collection chamber. The invention further relates to a measuring system with an enclosure and a method for measuring emissions, in particular tire abrasion.

[0002] An enclosure of this type for measuring tire wear is described in the publication “Philipps, Franz; Schripp, Tobias; Reiland, Sven; Bondorf, Linda; Löber, Manuel; Holtmann, Christoph (2023): ZEDU1 - Zero Emission Drive Unit Generation 1: Final report. Project report DLR. 209 pp.”

[0003] Furthermore, enclosures are known from the following non-patented literature: Bondorf, Linda; Köhler, Lennart; Grein, Tobias; Epple, Fabius; Philipps, Franz; Aigner, Manfred; Schripp, Tobias (2023): Air-borne brake wear emissions from a battery-electric vehicle. Atmosphere, 14, page 488. Multidisciplinary Digital Publishing Institute (MDPI). doi: 10.3390 / atmos14030488 https: / / doi.org / 10.3390 / atmos14030488; ISSN 2073-4433 - Bondorf, Linda; Grein, Tobias; Köhler, Lennart; Philipps, Franz; Schripp, Tobias (2022): On-board measurement of ultrafine non-exhaust particulate emissions from a battery electric vehicle. European Federation of Clean Air and Environmental Protection Associations Symposium (EFCA), July 5-6, 2022, Brussels, Belgium, - Philipps, Franz; Bondorf, Linda; Reiland, Sven (2023): ZEDU-1: Mobility without particulate matter emissions from brake and tire abrasion - Brake abrasion emissions of a battery-electric vehicle; (measurement) concepts and results. In: AVL-TechDay Brake Wear. AVL TechDay Brake Wear, March 7, 2023, Worms, and - Philipps, Franz; Bondorf, Linda; Epple, Fabius (2022): ZEDU-1 Zero Emission Drive Unit Phase 1: Mobility for tomorrow – Mobility without particulate matter emissions from brake and tire wear – (measurement) concepts and initial results. TechDay Brake Wear, July 5, 2022, Sindelfingen.

[0004] DE 10 2017 006 349 A1 discloses a measuring device comprising a wheel housing, a filter unit, and a measuring section. The housing seals around the wheel brake and has an inlet opening for supplying fresh air and an outlet opening for expelling emission-laden exhaust air from the housing. The filter unit is located at the inlet opening for filtering the fresh air. The measuring section includes an exhaust air duct, a measuring probe, and a volume flow measuring device. The emission-laden exhaust air is introduced into the exhaust air duct, and a partial volume flow of the emission-laden exhaust air is extracted by means of the measuring probe. This partial volume flow is then fed to the volume flow measuring device.

[0005] Further wheel housings for vehicles, for particle collection for the purpose of emission reduction, are specified in DE 10 2021 006 535 A1, DE 10 2021 107 506 B9 and DE 10 2019 133 794 B4.

[0006] DE 10 2016 215 900 A1, DE 10 2019 204 743 A1 and DE 10 2022 104 215 A1 disclose further methods and / or systems for determining and / or reducing tire emissions.

[0007] The invention is based on the objective of providing an enclosure as well as a measuring system with an enclosure and a method for measuring emissions, which enable an optimized measurement of tire abrasion.

[0008] The problem is solved for the enclosure with the features of claim 1, for the measuring system with the features of claim 15 and for the method with the features of claim 22.

[0009] The housing is designed so that the collector opening extends axially (with respect to the wheel's central axis) over more than 70% of the width, preferably between 80% and 95% of the width of the circumferential wall. Preferably, the collector opening is at least substantially rectangular and / or has a greater extent in the direction of rotation (around the wheel's central axis) than in the axial direction.

[0010] The emissions emanating from the vehicle wheel, in particular the tire, are preferably particulate emissions, especially tire abrasion.

[0011] “Essentially rectangular” means that the rectangular shape largely allows the perimeter wall to be covered by the collector opening over the height of the collector opening (i.e. its extent in the circumferential direction), with the sides being, for example, slightly curved for aerodynamic efficiency and / or the corners being rounded.

[0012] “Largely enclosed” means, in particular, interrupted in the direction of travel by the opening on the underside which, in the mounted state, points towards the subsoil.

[0013] In addition to the outer cover wall (arranged axially on a side of the enclosure facing away from the vehicle), the enclosure preferably has an inner cover wall (arranged axially on a side of the enclosure facing the vehicle). The inner cover wall separates the enclosure, in particular from a separate enclosure for a vehicle brake (brake enclosure), so that the emissions from the vehicle wheel can be captured separately from the emissions from the brake. The enclosure is attached to the brake enclosure, in particular by means of the inner cover wall, and to the vehicle, in particular by means of the brake enclosure. The outer and / or the inner cover wall(s) is / are, in particular, aligned orthogonally to the wheel's central axis and are semicircular in shape.

[0014] The circumferential wall is preferably aligned exclusively parallel to the wheel's central axis.

[0015] In this way, the enclosure is essentially cylindrical (e.g., apart from the opening on the ground side).

[0016] The greater extent in the direction of rotation than in width allows, for example, a larger inlet opening in a collector device and / or more precise positioning of the inlet opening relative to the direction of rotation with respect to an expected (main) particle flight direction. For example, the collector opening extends over an angular range between 15° and 35° in the direction of rotation.

[0017] Due to the relatively large design of the collector opening, extending (almost) across the entire (axial) width of the circumferential wall or housing, a large proportion of the particles carried by a gas, especially air, flow in the collection chamber can be advantageously transported out of the collection chamber by the collector device and measured, including those that, for example, do not completely follow the airflow due to their size and / or inertia. In this way, the measurement accuracy of tire abrasion is significantly optimized.

[0018] A favorable position with respect to the expected particle flight direction is achieved when the collector opening is preferably located in a quadrant of the housing that is rearward of the wheel (adjacent to the opening on the underside) relative to the front of the vehicle (in the mounted state), with respect to the direction of rotation around the wheel's central axis. For example, the collector opening extends in the direction of rotation almost adjacent to the opening on the underside (for example, with an interposed section of the circumferential wall, which is advantageous for mechanical stability and / or for mounting the collector device) to, for example, almost (for example, spaced at a maximum of 10° or 20°) an upper quadrant of the housing on the rear of the wheel.This positioning also allows heavier particles, which are carried along by the wheel movement but do not fully follow the airflow, to pass through the collector opening and out of the collection chamber.

[0019] In a particularly preferred embodiment, a collector device with a flow channel for transferring a gas flow onto a manifold is detachably (non-destructively) attached to the collector opening. This device has an inlet opening on the circumferential wall side, which is preferably at least substantially congruent with or smaller than the collector opening and / or (covered by the collector opening, ideally fluid-tight) attached to it. It also has an outlet opening on the manifold side, which is preferably at least substantially congruent with a flow cross-section of the manifold (ideally fluid-tight) and can be attached to or is attached to the manifold. For attachment, fastening options, such as bores around the collector opening, may be provided. The collector device preferably has a circumferential, flange-like contact surface for bearing against the circumferential wall.To increase fluid tightness, a circumferential sealing agent may be provided. The outlet opening has, in particular, a circular flow cross-section. Additionally or alternatively, the flow channel (with respect to its central axis) is preferably designed at least substantially tangentially to the vehicle wheel and arranged on the circumferential wall to substantially prevent flow deflection when air flows out of the collection chamber. In this way, the collector device serves, in particular, to transfer the large, in particular substantially rectangular, flow cross-section of the inlet opening to the, in particular, circular flow cross-section of the outlet opening.the collector pipe, and thus a flow path from the collection chamber to the collector pipe that is as streamlined as possible, and can advantageously be exchanged depending on the measurement task and / or housing for easy adaptation of the measuring system to other conditions (e.g., air volume flow and / or geometric discharge). The collector device is manufactured in particular by means of an additive manufacturing process (3D printing).

[0020] To generate isokinetic measurement conditions using a limited volume flow while still having a comparatively large collector opening, the collector device is preferably designed as a collecting nozzle with a flow cross-sectional constriction. The outlet opening can, for example, have a flow cross-section of up to 50% or up to 80% of that of the inlet opening.

[0021] For an advantageously compact design, the flow channel of the collector device preferably has a length (in the flow direction, with respect to a central axis of the flow channel) between 1.5 and 4 times the diameter of the flow cross-section of the outlet opening. The collector device is preferably designed to be aerodynamically efficient, with particularly continuous, rounded surface profiles and / or, if possible, without protrusions that induce flow separation. Optimization with regard to a favorable flow pattern is achieved in particular by means of computer-aided flow simulation. In this way, while maintaining a compact design of the collector device, the development of a fully, or at least largely, developed pipe flow within the collector pipe over the shortest possible distance is advantageously supported.

[0022] A broad particle spectrum can be advantageously collected if a reservoir, i.e., a depression oriented in the direction of gravity, is arranged on the underside (facing the substrate) of the collector device. The reservoir has a removable lid, for example, attached by a clip or magnetically, on its underside facing the substrate. The reservoir allows for the collection and analysis of heavier particles, which, due to their weight, cannot be carried by the airflow to the sampling device. The shape of the reservoir is specifically adapted to the surface profile of the underside of the flow channel of the collector device. The reservoir does not project into the area of ​​the opening facing the substrate with respect to the direction of circulation.

[0023] For possible pre-classification of the particles collected by the reservoir, a particle separation device, for example in the form of a grid and / or sieve or similar, can be arranged between the flow channel of the collector device and the reservoir. The hole or mesh size of the particle separation device is specifically adapted to its separation task.

[0024] In a preferred embodiment of the housing, an adapter opening is provided on the circumferential wall, preferably located in an upper quadrant (facing away from the opening on the underside), and more preferably in a quadrant on the front of the vehicle (in the mounted state) relative to the wheel's central axis. The adapter opening can be located, in particular, in the middle third of the upper, wheel-front quadrant in the direction of rotation. In this way, the adapter opening is located approximately opposite (relative to the wheel's central axis) the collector opening, allowing the vehicle wheel to be measured to be covered essentially completely around its circumference when a measuring airflow is added, thus advantageously enabling the collection of a large number of particles.

[0025] In particular, it is advantageously provided that a functional unit is detachably attachable or fixed to the adapter opening, wherein the functional unit comprises or is formed by (at least one of the following elements): a gas supply nozzle, a camera (and / or a camera mounting device), a particle injection device, and / or a measuring device. The particle injection device (or different particle injection devices) may, in particular, be configured for the injection of different types of particles, third-body elements, powder elements, and / or talc for the purpose of efficiency measurement, flow visualization, simulation of road dust, and / or maintaining certain tire properties to prevent changes in wear behavior. The measuring device may, for example, include a probe or the like.The gas supply nozzle preferably also has a comparatively wide supply opening, extending, for example, over more than 60% or 70% of the width of the circumferential wall, for the axially distributed supply of measuring gas, in particular measuring air, into the housing. The gas supply arrangement is preferably designed to add measuring air in a direction at least substantially tangential to the vehicle wheel and is arranged on the circumferential wall. One end of the gas supply nozzle, on the connection side, is preferably circular.

[0026] For measuring probes used for measurements near or on the vehicle wheel, there may also be additional openings in the housing, particularly on the circumferential wall.

[0027] In a design variant that offers advantages in terms of variable adaptability, the outer cover wall is detachably connected to the perimeter wall (without damage). For this purpose, the perimeter wall and / or the outer cover wall, in particular, have suitable fastening means.

[0028] For the purpose of inspecting the vehicle wheel and / or the collection chamber, it may be advantageous to provide that the outer cover wall is at least partially transparent, for example for inspection and / or flow measurement purposes.

[0029] To optimize measurement conditions, the housing, and optionally the collector device and / or at least part of the functional unit, can preferably be made of electrically conductive material, in particular metal and / or electrically conductive plastic. This applies especially to surfaces exposed to the current flow. This prevents static charging and the resulting measurement distortion caused by particles adhering to the housing surfaces.

[0030] Favorable flow conditions for particle collection within the collection chamber can be generated if the vehicle wheel occupies between 70% and 90%, preferably between 75% and 85%, e.g., 80%, of the volume enclosed by the housing. The remaining volume within the housing preferably forms the (clear) collection chamber. This dimensioning rule advantageously allows the generation of turbulent flow by means of a suitable volumetric flow rate of sample gas or mixed air.

[0031] Preferably, end elements are detachably attached to the opening-side ends of the (outer and / or inner) cover wall and / or the perimeter wall to limit the opening. These end elements are made of a different material than the cover wall(s) and / or the perimeter wall, and are particularly elastically deformable. The cover wall(s) and / or the perimeter wall preferably have suitable attachment points for securing the end elements to the opening. The distance between the enclosure and the substrate can be reduced by means of the end elements. Due to their elasticity, the end elements can preferably yield to unevenness in the substrate, thus preventing damage to the entire enclosure. The end elements represent a kind of "sacrificial element" that can be easily replaced after wear due to their detachable attachment.The end elements provide an improved, extensive separation of the airflow within the enclosure from the ambient air.

[0032] The measuring system according to the invention comprises an enclosure according to one of claims 3 to 14, comprising a collector device, as well as at least one analysis arrangement and a collecting line for directing air discharged from the enclosure to the analysis arrangement, wherein the collecting line is connected to an outlet opening of the collector device, wherein a sampling device of the analysis device is displaceable and / or releasable in the collecting line, downstream of the collector device, and is positioned or can be positioned in the collecting line, in particular displaceable and / or releasable along the direction of flow.

[0033] Preferably, the sampling device comprises at least one sampling probe, wherein the sampling probe and the flow cross-section of the collecting line are matched such that, when the sample is taken (with a supplied volume flow rate) from the discharged air, the change in flow velocity is less than 20%, i.e., isokinetic measurement conditions are present. The flow velocity is determined in particular by the requirements of one or more measuring units arranged downstream of the sampling device. The volume flow rate of the sample gas or air is also specifically matched to maintain the required flow velocity. The length of the collecting line is preferably such that at the position of one (or more) sampling opening(s) of the sampling device, at least a substantially fully developed pipe flow is present.For example, the distance between the outlet opening of the collector device (which corresponds to the inlet opening in the manifold) and the position of the sampling opening can be between 1.5 and 4 times the diameter of the manifold, for example, 2 times the diameter of the manifold. At least one sampling probe of the sampling device is preferably positioned such that the sampling opening is oriented orthogonally to a (main) flow direction of the airflow through the manifold.

[0034] Furthermore, the measuring system preferably includes a flow deflection (for example, by 90° with respect to the main airflow direction) and / or, in particular, a gas conveying device in the collecting line downstream of the sampling port of the sampling device. The flow deflection is preferably arranged downstream of the at least one sampling port such that inlet effects upstream of the flow deflection do not occur at the sampling port, for example, between 0.5 and 2 times the diameter of the collecting line.

[0035] Advantageously, measuring air can be supplied to the enclosure if the enclosure is equipped with a gas supply nozzle, wherein a supply line is connected to the gas supply nozzle, in which, in particular, a second gas conveying device for conveying gas, especially (measuring) air, to the enclosure is arranged. Preferably, a filter unit for generating filtered, clean measuring air is additionally or alternatively arranged in the supply line.

[0036] Preferably, at least one measuring device (or sensor unit) is provided on and / or inside the enclosure, designed and arranged for temperature measurement, in particular on the vehicle wheel centrally on a running surface, and / or for pressure measurement, and / or for flow measurement. The pressure measurement can, for example, include differential pressure measurement or absolute pressure measurement. In this way, for example, a speed-dependent pressure ratio between the enclosure and the environment can be determined.

[0037] Furthermore, the invention comprises a collector device designed for use on an enclosure according to one of the aforementioned embodiments, which is designed in particular according to one of the features described above relating to the collector device.

[0038] Furthermore, the invention relates to a gas supply nozzle designed for use on an enclosure according to one of the embodiments specified above, which is designed in particular according to one of the features described above relating to the gas supply nozzle.

[0039] The invention further relates to a method for measuring emissions emanating from a vehicle wheel, particularly particulate emissions, especially tire abrasion, using a measuring system according to one of the embodiments described above. In this system, an airflow is drawn from an enclosure and fed into a collecting line. Within the collecting line, a sample is isokinetically extracted from the airflow by means of a sampling device, and the remaining airflow is discharged to the environment. At the position of at least one extraction opening of the sampling device, a (at least substantially) fully developed pipe flow is present. Advantageous embodiments of the method are described analogously in connection with the enclosure and / or the measuring system.

[0040] The invention will now be explained in more detail using exemplary embodiments and with reference to the drawings. The drawings show: Fig. 1 a vehicle wheel with a housing according to the invention comprising a collector opening and an adapter opening in a perspective view of the vehicle wheel, Fig. 2 the enclosure according to Fig. 1 Top view of an outer cover wall, Fig. 3 A, B a collector device of the enclosure according to Fig. 1. Front view of an entrance opening ( Fig. 3A) and from the rear to a connection-side end ( Fig. 3B), Fig. 4 A, B the collector device according to Fig. 3 in perspective view from the front ( Fig. 4 A) and from behind ( Fig. 4 B), Fig. 5 the vehicle wheel with a further embodiment of the housing according to the invention comprising bottom-side end elements in a perspective view of the vehicle wheel and Fig. 6 a schematic representation of part of a measuring system according to the invention with a collecting line and a sampling device.

[0041] Fig. Figure 1 shows the wheel 2 of a vehicle (not shown here) in contact with a surface 3, which is enclosed by a housing 10 for collecting emissions, particularly particulate emissions, emanating from the wheel 2 during operation. The wheel 2 is rotationally symmetrical about a central axis M. An outer cover wall 12, which is arranged axially on a side of the housing 10 facing away from the vehicle, is in Fig. 1 is shown transparently, so that the vehicle wheel 2 is visible inside the enclosure 10.

[0042] The vehicle wheel 2 is, in this example, a car or truck tire. The housing 10 can also be used on a wheel of a rail vehicle.

[0043] Fig. Figure 2 shows the enclosure 10 without vehicle wheel 2 in a top view of the outer cover wall 12.

[0044] The enclosure 10 is in particular part of a measuring system 42 (partially shown in Fig. 6) for determining tire wear on a roller test bench and / or in a real environment (e.g., on a road or a rail). The measuring system 42 is designed to capture the particles emitted by the vehicle wheel 2 and to measure these particles, in particular without interference from contaminated ambient air. Preferably, the vehicle brake and the vehicle wheel 2 are enclosed separately. Within the enclosure 10, only the vehicle wheel 2, and not a vehicle brake, is located, so that the measuring system 42, comprising the enclosure 10, is used exclusively to determine the wheel and tire particle emissions.

[0045] The housing 10 comprises the semicircular outer cover wall 12, a semicircular inner cover wall 11 (arranged on the side of the housing 10 facing axially towards the vehicle in the assembled state) which is aligned in particular parallel to the outer cover wall 12, and a circumferential wall 14 attached between the outer cover wall 12 and the inner cover wall 11 at their radial outer sides. In the assembled state, the outer cover wall 12, the circumferential wall 14 and the inner cover wall 11 enclose a volume of the housing 10 within which the vehicle wheel 2 and a collection space 15 formed between the vehicle wheel 2 and the walls (cover walls 11, 12, circumferential wall 14) are located. The collection chamber 15 preferably has a constant radial height between the housing 10 and the vehicle wheel 2. Through a ground-side opening 18 within the housing 10, or...In the collection chamber 15, the vehicle wheel 2 is in contact with the surface 3.

[0046] The outer cover wall 12 and / or the inner cover wall 11 are aligned orthogonally to the wheel's central axis M. Both cover walls 11, 12 can, for example, be designed as smooth sheet metal. Alternatively or additionally, the outer cover wall 12 can be transparent, for example, made of fully transparent Plexiglas, e.g., for visual inspection of the vehicle wheel 2 and / or for flow visualization.

[0047] The inner lining 11 is preferably attached to a separate brake housing, which in turn is attached to the vehicle (not shown here). The housing 10 is attached to the vehicle by means of the inner lining 11 being attached to the brake housing.

[0048] The circumferential wall 14 of the housing 10 is arranged between the radial outer surfaces of the inner cover wall 11 and the outer cover wall 12. This circumferential wall 14 encloses the vehicle wheel 2, interrupted by the opening 18 on the underside, preferably in a circular fashion, e.g., within an angular range with respect to the direction of rotation around the wheel's central axis M between 240° and 300°. The opening 18 on the underside is each bounded by a preferably straight end of the cover walls 11, 12 and the circumferential wall 14, e.g., aligned parallel to the (flat) surface 3. The bottom-side ends of the cover walls 11, 12 run in a kind of circular chord along the semicircular shape of the cover walls 11, 12. By means of this design, on the one hand the vehicle wheel 2 can be largely shielded from its surroundings and on the other hand sufficient ground clearance of the housing 10 can be maintained.The shielding from the ambient air can be improved by end elements 40 that can be attached to mounting openings 13 (see . Fig. 5).

[0049] The circumferential wall 14 is preferably aligned axially exclusively parallel to the wheel's central axis M. In the axial direction, the circumferential wall 14 has a width B, which is in particular constant, and which is greater than the axial width of the vehicle wheel 2.

[0050] The outer cover wall 12 is preferably detachably attached to the perimeter wall 14 in a non-destructive manner, so that the outer cover wall 12 can be removed and reattached for setup and / or assembly purposes and / or for attaching different types of outer cover walls 12 (for example, made of sheet metal or transparent). For this purpose, fastening means 16 are preferably provided around the perimeter of the perimeter wall 14, in this case, for example, eight.

[0051] The enclosure 10 is optimized to collect emissions emanating from the vehicle wheel 2, especially particulate emissions, in particular tire abrasion, as completely as possible and to remove them from the collection chamber 15 for measurement purposes.

[0052] For this purpose, a collector opening 19 is provided in the circumferential wall 14, through which air laden with emissions, particularly particulate emissions, can be discharged from the collection chamber 15, or is discharged during operation. For optimized particle removal, the collector opening 19 extends axially over more than 70% of the width B of the circumferential wall 14, preferably between 80% and 95% of the width B of the circumferential wall 14. The extent of the collector opening 19 in the circumferential direction is preferably greater than the width B, i.e., in the axial direction. In order to cover as large an axial area of ​​the circumferential wall 14 as possible, the collector opening 19 is preferably at least substantially rectangular (for example, apart from aerodynamically rounded corners and / or slightly curved longitudinal sides).

[0053] How especially Fig. As shown in Figure 2, the collector opening 19 is located in a wheel-rear, ground-side quadrant Q2 with respect to the wheel center axis M (relative to the front of the vehicle). For example, the collector opening 19 extends in the direction of rotation over an angular range of 10° to 35° with respect to the wheel center axis M. In this way, the collector opening 19 is located in a position favorable with respect to the direction of flight of the particle emissions.

[0054] The enclosure 10 with the volume and the collection chamber 15 is dimensioned such that the vehicle wheel 2 occupies between 70% and 90%, preferably between 75% and 85%, e.g., 80% of the collection chamber 15 within the enclosure 10. In this way, a turbulent (air) flow, advantageous for particle transport, can be generated within the collection chamber 15 during operation.

[0055] To transfer at least part of the flow within the collection chamber 15 to a collecting line 44 of the measuring system 42 (see Fig. 6) A collector device 20 with a flow channel 27 is detachably attached to the collector opening 19. Due to the detachable attachment, a collector device 20 optimized for a specific housing 10 and / or measurement task and / or measurement condition can be used.

[0056] Fig. 3A and Fig. Figure 3B shows the collector device 20 in a top view from the front, looking towards an inlet opening 24 ( Fig. 3A) and from the rear, to a connection-side end 26 with an outlet opening 25 ( Fig. 3B). Fig. 4A and Fig. Figure 4B shows the collector device 20 in a perspective view from the front ( Fig. 4A) and from behind ( Fig. 4B).

[0057] The inlet opening 24 is arranged on the side of the circumferential wall 14 in the assembled state and is, for example, essentially congruent with the collector opening 19. The inlet opening 24 can also be smaller, particularly with a smaller extent in the direction of rotation than the collector opening 19, wherein the inlet opening 24 is positioned on the circumferential wall 14 in the direction of rotation, particularly in accordance with an expected particle flight direction above the collector opening 19.

[0058] To ensure the most fluid-tight possible attachment of the collector device 20 to the circumferential wall 14, the collector device 20 has a contact surface 21 around the inlet opening 24, shaped complementarily to the circumferential wall 14 in the corresponding area. The contact surface 21 preferably rests against the circumferential wall 14 around the collector opening 19 over a surface area, for example, with the interposition of a sealing agent 23 arranged around the collector opening 19 or the inlet opening 24.

[0059] The outlet opening 25 on the manifold side is designed to be at least substantially identical to the flow cross-section of the subsequent manifold 44, which is attached to the collector device 20 in a fluid-tight manner (as far as possible) during measurement operation. The flow cross-section is, in particular, circular.

[0060] The collector device 20 serves to transfer the flow cross-section optimized for particle collection at the inlet opening 24 to the flow cross-section optimized for sample extraction at the outlet opening 25 in the most flow-efficient manner possible.

[0061] For this purpose, the collector device 20 is preferably designed as a collecting nozzle 22 with a flow cross-sectional constriction. The outlet opening 25 can, for example, comprise a maximum of 70% or a maximum of 50% of the flow cross-sectional area of ​​the inlet opening 24. The cross-sectional constriction is particularly important, taking into account the measurement conditions, to maintain an isokinetic flow velocity between the collecting line 44 and a sampling device 46 (see Figure 1). Fig. 6) adapted, whereby, given a given supplied airflow (for example limited by components within a supply line to the housing 10), a flow velocity that is as constant as possible (for example with a deviation of a maximum of 20%) is sought between the collecting line 44 and the sampling device 46.

[0062] The collector device 20 is preferably shaped and arranged in a flow-optimized manner, having a continuous wall profile, particularly in the flow direction, and preferably without turbulence-inducing discontinuities (e.g., changes in cross-section). The flow channel 27 (with respect to its central axis) extends outwards, for example, with a largely tangential directional component relative to the vehicle wheel 2, whereby, at least on the inlet side, the wall on the lower side of the collector device 20 and on the outlet side (towards the outlet opening 25) extends radially outwards and in the direction of rotation (i.e., relative to the surface 3, cf. Fig. 1) is directed upwards. This prevents an abrupt flow deflection when the airflow is discharged from the collection chamber 15. The inclination of a central axis of the flow channel 27 is (in the assembled state) e.g. between 15° and 25° to the (flat) surface 3. These design features advantageously reduce inlet effects of the airflow over the shortest possible distance during discharge and achieve a substantially complete pipe flow within the cylindrical connection-side end 26 and / or the collecting pipe 44, thus enabling precise particle measurement. Turbulence generated within the collection chamber 15 is significantly reduced. Therefore, the collector device 20 can advantageously be designed to be comparatively short, with the flow channel 27, for example, having a length (in the flow direction) between 1.5 and 4 times the diameter of the flow cross-section of the outlet opening 25 in the direction of rotation.

[0063] How especially Fig. 3B and Fig. As shown in Figure 4B, a reservoir 28 for collecting larger particles that are not transported by the flow to the collecting line 44 can be arranged on the underside of the collector device 20. The reservoir 28 preferably has a removable lid 29 on its underside, from which particles collected in the reservoir 28 can be easily removed.

[0064] Between the flow channel 27 and the reservoir 28, a particle separation device, for example a grid-like and / or sieve-like device adapted to a separation task, can be arranged (not shown here).

[0065] How Fig. 1 and Fig. As further shown in Figure 2, an adapter opening 30 is preferably arranged on the circumferential wall 14, which, for example, is located in an upper, wheel-front quadrant Q4 (with respect to the front of the vehicle) with respect to the wheel center axis M (see Figure 2). Fig. 2) is arranged, e.g., in its middle third with respect to the direction of rotation. The adapter opening 30 preferably also extends axially over more than 70%, for example, between 75% and 90% of the width B of the circumferential wall 14, and has, for example, a smaller extent in the direction of rotation than the width B.

[0066] A functional unit 32 is detachably or attachably attached to the adapter opening 30. Fig. 1 and Fig. 2 The functional unit 32 is formed by a gas supply nozzle 34, which has, for example, a substantially rectangular supply opening 38 on the circumferential wall 14 and, on the opposite side, a particularly circular, connection-side end 36. The gas supply nozzle 34 is, for example, largely oriented with a tangential directional component with respect to the vehicle wheel 2, for example, orthogonal to the surface 3 (in the mounted state, cf. Fig. 1) The functional unit 32 may alternatively or additionally include or be formed from a camera or a camera mounting device for optical measurement purposes, a particle addition device and / or a measuring device.

[0067] In addition to the adapter opening 30, further openings not shown here may be present on the housing 10 for measuring purposes, for example for pressure measurement in the center with respect to the running surface of the vehicle wheel 2.

[0068] The housing 10, and optionally the collector device 20 and / or the functional unit 32, are preferably made at least partially of electrically conductive material, such as metal and / or electrically conductive plastic. This applies in particular to areas that come into contact with the airflow, which are preferably made entirely of such a material. This design advantageously prevents static charging of areas or parts of the housing 10 exposed to the airflow, which could influence particle transport and distort the measurement.

[0069] Fig. Figure 5 shows another preferred embodiment of the enclosure 10, wherein, to limit the opening 18 on the ground side, the end elements 40 are detachably fastened at the respective opening-side ends of the outer cover wall 12 and the perimeter wall 14, and optionally and detachably at the inner cover wall 11 (not shown here). Fig. Figure 5 shows the end elements 40 schematically and exemplarily in transparent form. The end elements 40 are preferably made of a different material than the cover walls 11, 12 and / or the circumferential wall 14, and are in particular elastically deformable. The end elements 40 reduce the distance between the enclosure 10 and the substrate 3, and, due to their elasticity, can yield to unevenness in the substrate 3, thus preventing damage to the entire enclosure 10. The end elements 40 represent a kind of "sacrificial element" that can be easily replaced after wear due to their detachable fastening. The end elements 40 provide improved, extensive separation of the airflow within the enclosure 10 from the ambient air.

[0070] In the rest of the training, the Fig. 5 shown enclosure 10 e.g. the one in Fig. 1 shown enclosure 10.

[0071] Fig. Figure 6 schematically shows a part of the measuring system 42 downstream of the housing 10, including the cylindrical collecting line 44 and the sampling device 46. The sampling device 46 is associated with an analysis arrangement for particle emission analysis, which is not shown in detail here and may have different measuring units. The sampling device 46 has one or more, in Fig. 6. For example, four sampling probes 48, for instance one sampling probe 48 per measuring unit.

[0072] The sampling probes 48 project coaxially into the collecting pipe 44, with the respective sampling openings 50 preferably oriented orthogonally to the main flow direction to avoid flow deflection during sampling. The sampling openings 50 of the sampling probes 48 are positioned in the collecting pipe 44 at a distance from the collector device 20 in the flow direction such that at least substantially full pipe flow is present at the sampling position. The air (volume) flow rate and the flow diameter of the collecting pipe 44 are matched to the sampling probe 48 such that isokinetic sampling occurs, with the change in the flow velocity of the particle-laden airflow during sample extraction from the collecting pipe 44 into the sampling probe 48 being less than 20%.

[0073] In order to ensure at least a largely developed pipe flow for different measuring tasks and / or measuring units, the sampling device 46 is axially displaceable (along the flow direction) and / or detachable on the collecting pipe 44.

[0074] In this way, the axial position (in the direction of flow) of the sampling probe(s) 48 within the collecting line 44 can be changed and / or the collector device 20 can be exchanged, and thus these components can be optimized and coordinated for a specific measurement task within the measuring system 42.

[0075] Downstream of the sampling openings 50, a flow deflector 52 is provided, through which the residual air can be discharged via the collecting line 44 downstream of the sampling openings 50. The distance of the sampling openings 50 to the flow deflector 52 (with respect to an upstream edge) is, for example, between 0.5 and 3 times the flow diameter of the collecting line 44, in order to prevent the influence of inlet effects at the flow deflector 52 on the upstream sampling process. The flow deflector 52 is formed here as a transition between the sampling section of the collecting line 44 and a cylindrical pipe section arranged, for example, at 90° to it. Downstream of the flow deflector 52, a plate 54 is preferably positioned to provide a fluid-tight seal for the collecting line 44 in the direction of the measuring units, thereby supporting the flow deflector 52.

[0076] Downstream of the flow deflection 52, in a further line of the measuring system 42 for the residual air supply, a gas conveying device 56 can be provided for conveying the airflow from the collector device 20 and downstream of it. An outlet for releasing the residual air to the environment is preferably provided downstream of the gas conveying device 56 (not shown here).

[0077] The measuring system 42 preferably comprises further components not shown here, for example, a (second) gas supply device for supplying gas, in particular air, in a supply line from the housing to the housing 10. Furthermore, the measuring system 42 preferably comprises one or more additional measuring devices, which are used, for example, for measuring temperature and / or pressure at the vehicle wheel 2 (for example, at a position centrally on its running surface) and / or for measuring the flow rate of measuring air supplied to and / or discharged from the housing. A filter unit for providing purified air for measuring purposes may also preferably be arranged in the supply line (each not shown here).

[0078] In an exemplary measurement operation, the vehicle wheel 2, in particular defined, moves on the surface 3, e.g., of a roller test stand or a real road surface. Preferably purified (measurement) air is supplied to the collection chamber 15 of the housing 10 via the functional unit 32, which is designed, for example, as a gas supply nozzle 34. The mass or volume flow rate is such that isokinetic conditions are maintained by means of the sampling device 46, whereby a turbulent flow develops within the collection chamber 15 due to its dimensions relative to the vehicle wheel 2. A particle-laden airflow is discharged from the collection chamber 15 via the collector device 20, for example, when the gas conveying device 56 is in operation. The discharged mass or volume flow rate preferably corresponds substantially to that of the supplied measurement air, e.g., + / - 10%.This airflow is fed isokinetically to the sampling device 46 via the collecting line 44, with a fully developed pipe flow preferably present at the position of the sampling opening(s) 50 of the sampling device 46. The collector device 20 and the collecting line 44 are coordinated for isokinetic sampling with a fully developed pipe flow (in particular with regard to the flow cross-sections and the length of the flow paths), with the collector device 20 being designed accordingly, taking the measurement task into account. The mass or volume flow rate of the air is determined in particular by the required flow velocities within the measuring units.

[0079] Due to its variable design, the enclosure 10 allows for the performance of various measurement tasks, for example, with the addition of different types of particles, third-body elements, powder elements, and / or talc for flow visualization, simulation of road dust, and / or maintenance of specific tire properties to prevent changes in wear behavior. It is also possible to forgo adding air to the enclosure 10, with ambient air flowing in, for example, through the opening 18 on the underside. For example, for the inspection of the vehicle wheel 2 and / or the flow behavior, the outer cover wall 12 can advantageously be mounted in a transparent design. QUOTES INCLUDED IN THE DESCRIPTION

[0000] This list of documents cited by the applicant was automatically generated and is included solely for the reader's convenience. The list is not part of the German patent or utility model application. The DPMA accepts no liability for any errors or omissions. Cited patent literature

[0000] DE 10 2017 006 349 A1

[0004] DE 10 2021 006 535 A1

[0005] DE 10 2021 107 506 B9

[0005] DE 10 2019 133 794 B4

[0005] DE 10 2016 215 900 A1

[0006] DE 10 2019 204 743 A1

[0006] DE 10 2022 104 215 A1

[0006] Cited non-patent literature

[0000] Philipps, Franz; Schripp, Tobias; Reiland, Sven; Bondorf, Linda; Löber, Manuel; Holtmann, Christoph (2023): ZEDU1 - Zero Emission Drive Unit Generation 1: Final Report. DLR Project Report. 209 pp.

[0002] Bondorf, Linda; Köhler, Lennart; Grein, Tobias; Epple, Fabius; Philipps, Franz; Aigner, Manfred; Schripp, Tobias (2023): Air-borne brake wear emissions from a battery-electric vehicle. Atmosphere, 14, page 488. Multidisciplinary Digital Publishing Institute (MDPI). doi: 10.3390 / atmos14030488 https: / / doi.org / 10.3390 / atmos14030488; ISSN 2073-4433

[0003] Bondorf, Linda; Grein, Tobias; Köhler, Lennart; Philipps, Franz; Schripp, Tobias (2022): On-board measurement of ultrafine non-exhaust particulate emissions from a battery electric vehicle. European Federation of Clean Air and Environmental Protection Associations Symposium (EFCA), July 5-6, 2022, Brussels, Belgium

[0003] Philipps, Franz; Bondorf, Linda; Reiland, Sven (2023): ZEDU-1: Mobility without particulate matter emissions from brake and tire abrasion - Brake abrasion emissions of a battery-electric vehicle; (measurement) concepts and results. In: AVL-TechDay Brake Wear. AVL TechDay Brake Wear, 07.03.2023

[0003] Philipps, Franz; Bondorf, Linda; Epple, Fabius (2022): ZEDU-1 Zero Emission Drive Unit Phase 1: Mobility for tomorrow. Mobility without particulate matter emissions from brake and tire wear – (measurement) concepts and initial results. TechDay Brake Wear, July 5, 2022

[0003]

Claims

[1] Housing (10) for a vehicle wheel (2) for collecting emissions emanating from the vehicle wheel (2), which largely encloses the vehicle wheel (2) and a collection chamber (15), comprising an outer cover wall (12) extending radially with respect to a wheel central axis (M) and a circumferential wall (14) adjoining the cover wall (12), extending in the direction of rotation around the wheel central axis (M), and having a width (B) in the axial direction, wherein an opening (18) on the underside is arranged in the circumferential wall (14) through which the vehicle wheel (2) can be in contact with a surface (3), and wherein a collector opening (19) is provided in the circulation wall (14) through which air loaded with emissions can be discharged from the collection chamber (15), characterized by , that the collector opening (19) extends in the axial direction over more than 70% of the width (B), preferably between 80% and 95% of the width (B) of the circumferential wall (14), and is preferably at least substantially rectangular and / or preferably has a greater extent in the circumferential direction than in the axial direction. [2] Enclosure (10) according to claim 1, characterized by , that the collector opening (19) is arranged in a quadrant (Q2) of the housing (10) on the rear side of the wheel of a vehicle, on the underside. [3] Enclosure (10) according to claim 1 or 2, characterized by, that a collector device (20) with a flow channel (27) for transferring a gas flow to a collecting pipe (44) is detachably attached to the collector opening (19), with an inlet opening (24) which is preferably at least substantially identical to or smaller than the collector opening (19) and / or attached to it, and with a collector pipe-side outlet opening (25) which is preferably at least substantially identical to a flow cross-section of the collecting pipe (44) and can be attached to it or is attached to it. [4] Enclosure (10) according to claim 3, characterized by , that the collector device (20) is designed as a collecting nozzle (22) with a flow cross-sectional narrowing. [5] Enclosure (10) according to claim 3 or 4, characterized by, that the flow channel (27) of the collector device (20) has a length between 1.5 times and 4 times the diameter of a flow cross-section of the outlet opening (25) in the direction of circulation. [6] Enclosure (10) according to one of claims 3 to 5, characterized by , that a reservoir (28) is arranged on an underside of the collector device (20) on the subsurface. [7] Enclosure (10) according to claim 6, characterized by , that a particle separation device is arranged between the flow channel (27) of the collector device (20) and the reservoir (28). [8] Enclosure (10) according to any of the preceding claims, characterized by , that an adapter opening (30) is further arranged on the circumferential wall (14), which is preferably arranged in an upper, particularly preferably a wheel-front quadrant (Q4) with respect to the wheel center axis (M) of a vehicle front. [9] Enclosure (10) according to claim 8, characterized by, that a functional unit (32) can be detachably attached or is attached to the adapter opening (30), wherein the functional unit (32) comprises or is formed by: a gas supply nozzle (34), a camera, a particle addition device and / or a measuring device. [10] Enclosure (10) according to any one of the preceding claims, characterized by , that the outer cover wall (12) is detachably connected to the circumferential wall (14). [11] Enclosure (10) according to any of the preceding claims, characterized by , that the outer cover wall (12) is at least partially transparent. [12] Enclosure (10) according to any one of the preceding claims, characterized by , that the housing (10) and, if applicable, the collector device (20) and / or at least partially the functional unit (32) is / are made of electrically conductive material, in particular metal and / or electrically conductive plastic. [13] Enclosure (10) according to any of the preceding claims, characterized by , that the vehicle wheel (2) occupies between 70% and 90%, preferably between 75% and 85%, e.g. 80%, of the volume enclosed by the housing (10). [14] Enclosure (10) according to any one of the preceding claims, characterized by , that to limit the opening (18) on the underside, end elements (40) are detachably attached to the opening-side ends of the top wall (12) and / or the perimeter wall (14), which are made of a different material than the top wall (12) and / or the perimeter wall (14), in particular elastically deformable. [15] Measuring system (42) with an enclosure (10) according to one of claims 3 to 14 comprising a collector device (20), with at least one analysis arrangement and a collecting line (44) for conveying air discharged from the enclosure (10) to the analysis arrangement, wherein the collecting line (44) is connected to an outlet opening (25) of the collector device (20), wherein a sampling device (46) of the analysis device is displaceable and / or releasable in the collecting line (44), downstream of the collector device (20). [16] Measuring system (42) according to claim 15, characterized bythat the sampling device (46) has at least one sampling probe (48), wherein the sampling probe (48) and the flow cross-section of the collecting line (44) are matched such that when the sample is taken from the discharged air, the change in the flow velocity is less than 20%. [17] Measuring system (42) according to claim 15 or 16, characterized by , that downstream of the position of a sampling opening (50) of the sampling device a flow deflection (52) and / or, in particular downstream of the flow deflection (52), a gas conveying device (56) is / are arranged in the collecting line (44). [18] Measuring system (42) according to one of claims 15 to 17, characterized by, that the housing (10) according to claim 9 is designed with a gas supply nozzle (34), wherein a supply line is connected to the gas supply nozzle (34), in which in particular a second gas conveying device, for conveying gas, in particular air, to the housing (10) is arranged. [19] Measuring system (42) according to any one of claims 15 to 18, characterized by , that at least one measuring device is present on and / or inside the housing (10), which is designed and arranged for temperature measurement, in particular on the vehicle wheel (2) centrally on a running surface and / or for pressure measurement and / or for flow measurement. [20] Collector device (20) designed for use on an enclosure (10) according to any one of claims 1 to 14. [21] Gas supply nozzle (20) designed for use on an enclosure (10) according to any one of claims 9 to 14. [22] Method for measuring emissions, in particular particulate emissions, emanating from a vehicle wheel (2) with a measuring system (42) according to one of claims 15 to 19, in which an airflow is drawn from an enclosure (10) and fed to a collecting line (44), wherein within the collecting line (44) a sample is isokinetically taken from the airflow by means of a sampling device (46) and the remaining airflow is discharged to an environment, wherein at the position of at least one sampling opening (50) of the sampling device (46) there is at least substantially a fully developed pipe flow.

Images