A vehicle exhaust cooling system and exhaust gas treatment assembly

Abstract

This invention relates to the field of automotive component technology, specifically to an automotive exhaust cooling system and exhaust gas treatment assembly. The cooling system includes: a first air outlet of an expansion chamber with a cross-sectional area larger than that of a first air inlet; the first air outlet of the expansion chamber is connected to the cooling channel; a turbulence-inducing assembly includes an outer ring, a central hub, and multiple turbulence-inducing blades, which are inclined along the exhaust gas flow direction to generate swirling flow when the exhaust gas flows through the guide channel. This invention reduces the exhaust gas velocity and prolongs the residence time by expanding the chamber, and, combined with the turbulence-inducing assembly, diverts the airflow and induces swirling flow, significantly enhancing the exhaust gas turbulence intensity and fluid mixing effect, improving the heat exchange efficiency with the channel wall, thereby achieving efficient cooling; at the same time, it has a compact structure, adapting to the layout requirements of short-path exhaust systems.

Description

Technical Field

[0001] This invention relates to the field of automotive component technology, specifically to an automotive exhaust cooling system and exhaust gas treatment assembly. Background Technology

[0002] With increasingly stringent vehicle emission regulations and continuous optimization of vehicle layout space, modern automotive exhaust systems exhibit a clear trend towards compactness and shorter exhaust paths. This means minimizing exhaust pipe length within limited chassis space to meet the demands of vehicle lightweighting and space integration. However, while shortening the exhaust path facilitates layout optimization, it also reduces the time and space for natural heat dissipation of exhaust gases within the pipes, causing the exhaust gases to remain at a relatively high temperature when entering the aftertreatment system and tailpipe structure.

[0003] Under these circumstances, the direct discharge of high-temperature exhaust gas can easily cause the exhaust system and surrounding components to be under continuous high heat load, thereby accelerating material thermal aging and structural fatigue. Therefore, how to reduce the temperature of exhaust gas in a shorter exhaust path is a current research direction. Summary of the Invention

[0004] (a) Purpose of the invention The purpose of this invention is to provide an automotive exhaust cooling system and exhaust gas treatment assembly. By expanding the cavity to reduce the exhaust gas velocity and extend the residence time, and combining the turbulence component to divert the airflow and induce the formation of swirl, the system significantly enhances the exhaust gas turbulence intensity and fluid mixing effect, improves the heat exchange efficiency with the flow channel wall, and thus achieves efficient cooling. At the same time, the system has a compact structure and is suitable for the layout requirements of short-path exhaust systems.

[0005] (II) Technical Solution To address the above problems, the present invention provides an automotive exhaust cooling system, comprising: an expansion cavity, a turbulence-disrupting component, and a cooling channel; The expansion cavity includes a first air inlet and a first air outlet, wherein the cross-sectional area of ​​the first air outlet is larger than the cross-sectional area of ​​the first air inlet. The first air outlet of the expansion cavity is connected to the cooling channel, and the turbulence component is disposed in the cavity inside the cooling channel; The aerodynamic component includes an outer ring, a central hub, and multiple aerodynamic blades; The outer ring is coaxially connected to the cooling channel, the central hub is located at the center of the outer ring, and a plurality of the baffles are arranged at intervals along the circumference of the central hub. One end of each baffle is fixedly connected to the central hub, and the other end of each baffle is fixedly connected to the outer ring. The plurality of baffles together form a plurality of guide channels for the exhaust gas to pass through. The turbulence blades are inclined along the exhaust gas flow direction so that the exhaust gas will generate swirling flow when it passes through the guide channel.

[0006] In another aspect of the present invention, preferably, the turbulence-disrupting component further includes: a temperature control component and a rotating shaft; Each of the deflection blades corresponds to a set of temperature control components and a rotating shaft. Each of the deflection blades is connected to the central hub through the rotating shaft. The temperature control components adjust the working angle of the deflection blades through the rotating shaft. The central hub is configured as a frustum shape, with the cross-sectional area of ​​the first end of the central hub being smaller than that of the second end of the central hub. The first end of the central hub is the end closest to the air outlet, so that the outer circumferential surface of the central hub forms a clearance surface that gradually contracts towards the air outlet, providing clearance space for the deflection of the spoiler blades around the rotating axis.

[0007] In another aspect of the present invention, preferably, the working angle range of the deflector blade is 35° to 65°, and the temperature control component is configured as a shape memory alloy spring; When the shape memory alloy spring senses an increase in temperature and deforms and elongates, it drives the corresponding spoiler blades to rotate via the rotating shaft, increasing the working angle.

[0008] In another aspect of the present invention, preferably, The central hub, rotating shaft, and spoiler blades are all provided with internal cavities, and the central hub, rotating shaft, and spoiler blades are internally connected; The central hub is provided with a hub air inlet, and each of the deflector blades is provided with multiple jet holes; The hub air intake is connected to the outside atmosphere. Outside air enters the interior of the central hub, shaft and spoiler blades through the hub air intake and is ejected through the jet hole.

[0009] In another aspect of the present invention, preferably, the hub air inlet is disposed on the end face or side wall of the central hub that is close to the outside atmosphere, and communicates with the internal cavity of the central hub; The jet hole is disposed on the outer surface of the baffle blade facing the inner cavity of the cooling channel and communicates with the inner cavity of the baffle blade.

[0010] In another aspect of the invention, preferably, the jet holes are arranged at intervals along the length direction of the deflector blades, and the diameter of adjacent jet holes gradually decreases along the exhaust gas flow direction.

[0011] In another aspect of the present invention, preferably, the jet direction of the jet hole is set at a preset angle relative to the surface normal direction of the turbulence blade, so that the external gas enters the cooling channel along the tangential component to form an ejector flow field.

[0012] In another aspect of the present invention, preferably, the inner wall of the expansion cavity is provided with a plurality of flow-guiding protrusions, the flow-guiding protrusions being arranged at intervals along the circumference of the expansion cavity.

[0013] In another aspect of the present invention, preferably, the cross-section of the flow-guiding protrusion structure is streamlined or semi-elliptical, the front side of the flow-guiding protrusion structure is a circular arc transition, and the back side is a gradually tapering slope.

[0014] In another aspect of the present invention, preferably, an exhaust gas treatment assembly includes the automotive exhaust cooling system as described above, and the exhaust gas treatment assembly further includes: a first exhaust tailpipe, a rear muffler, a second exhaust tailpipe, an active valve, and an active valve drive-by-wire system. The first exhaust tailpipe is connected to the rear muffler, and the rear muffler is connected to the vehicle exhaust cooling system via the second exhaust tailpipe. The active valve and the active valve drive-by-wire system are located at the second exhaust tailpipe. The active valve is used to adjust the exhaust switching in the second exhaust tailpipe according to the control signal of the active valve wire control system.

[0015] (III) Beneficial Effects The above-described technical solution of the present invention has the following beneficial technical effects: This invention utilizes an expansion cavity to cause a sudden expansion of the exhaust gas's cross-section upon entry into the system. This reduces the airflow velocity and prolongs the residence time within the system, providing more sufficient heat exchange conditions for the exhaust gas to diffuse to the outside, thus contributing to initial cooling. Furthermore, a turbulence assembly consisting of an outer ring, a central hub, and multiple turbulence blades is incorporated within the cooling channel. This divides the exhaust gas into multiple guide channels, ensuring sufficient contact between the airflow and the channel walls and turbulence structure during its flow, significantly improving convective heat transfer efficiency. Simultaneously, the turbulence blades are arranged at an angle along the exhaust gas flow direction, creating a swirling effect as the exhaust gas passes through the guide channels. This enhances the turbulence intensity and mixing degree, promoting heat exchange between high-temperature gases and between the gas and the wall, further improving cooling capacity. Moreover, the outer ring, central hub, and turbulence blades form a stable integrated structure, maintaining channel continuity while ensuring the turbulence effect and avoiding the formation of local flow dead zones. The overall structure is compact, achieving highly efficient exhaust gas cooling, and is suitable for the compact design requirements of automotive exhaust systems. Attached Figure Description

[0016] Figure 1 This is a schematic diagram of the overall structure of an automotive exhaust cooling system according to an embodiment of the present invention; Figure 2 This is a schematic diagram of the temperature control component structure according to an embodiment of the present invention; Figure 3This is a schematic diagram of the overall structure of the exhaust gas treatment assembly according to an embodiment of the present invention; Figure label: 1: Expanding the cavity, 2: spoiler assembly; 210: center hub; 220: spoiler blades; 230: temperature control component. 3: Cooling flow channels 4: First exhaust tailpipe, 5: Rear muffler 6: Second exhaust tailpipe, 7: Active valve wired control system. Detailed Implementation

[0017] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to specific embodiments and the accompanying drawings. It should be understood that these descriptions are merely exemplary and not intended to limit the scope of the invention. Furthermore, descriptions of well-known structures and techniques are omitted in the following description to avoid unnecessarily obscuring the concept of the invention.

[0018] The accompanying drawings show structural schematic diagrams according to embodiments of the present invention. These drawings are not drawn to scale, and some details have been enlarged for clarity, and some details may have been omitted. The shapes of the various regions and layers shown in the drawings, as well as their relative sizes and positional relationships, are merely exemplary and may deviate from reality due to manufacturing tolerances or technical limitations. Furthermore, those skilled in the art can design regions / layers with different shapes, sizes, and relative positions as needed.

[0019] Obviously, the described embodiments are only some, not all, of the embodiments of the present invention. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without inventive effort are within the scope of protection of the present invention.

[0020] Furthermore, the technical features involved in the different embodiments of the present invention described below can be combined with each other as long as they do not conflict with each other.

[0021] The invention will now be described in more detail with reference to the accompanying drawings. In the various drawings, the same elements are indicated by similar reference numerals. For clarity, the various parts in the drawings are not drawn to scale.

[0022] Example 1 A car exhaust cooling system Figure 1 A schematic diagram of the overall structure of an automotive exhaust cooling system according to an embodiment of the present invention is shown, as follows: Figure 1 As shown, it includes: an expansion cavity 1, a turbulence assembly 2, and a cooling channel 3; The expansion cavity 1 includes a first air inlet and a first air outlet, with the cross-sectional area of ​​the first air outlet being larger than that of the first air inlet. As the first-stage energy release structure for exhaust gas entering the cooling system, the expansion cavity 1 forms an abrupt cross-sectional channel that transitions from contraction to expansion. After entering through the first air inlet, the exhaust gas flow rate decreases significantly due to the gradually increasing cross-sectional area, reaching its maximum at the first air outlet. Simultaneously, the static pressure rises, creating a typical expansion and deceleration effect, thereby reducing the initial kinetic energy of the exhaust gas and weakening its impact intensity. The expansion cavity 1 can adopt a cylindrical, gradually expanding conical, or combined expansion structure, and its inner wall can be made of a high-temperature resistant material. The ratio between the first air inlet and the first air outlet of the expansion cavity 1 is not limited here; it can be selected and optimized based on engine displacement, exhaust gas flow rate, exhaust pulsation frequency, allowable back pressure, and target cooling effect. When the area ratio of the first outlet to the first inlet increases, the exhaust gas expansion is enhanced, and the flow velocity reduction is more significant. This helps to prolong the residence time of the exhaust gas in the expansion cavity 1 and the subsequent cooling channel 3, thereby improving the heat exchange efficiency between the exhaust gas and the cooling structure. When the area ratio is relatively small, a higher exhaust gas flow velocity can be maintained, reducing the increase in system back pressure, which is suitable for operating conditions with large exhaust flow. Therefore, the area ratio of the two can be reasonably matched according to different vehicle models, engine power, and exhaust gas treatment requirements to balance cooling efficiency, exhaust resistance, flow field stability, and system structural dimensions, so that the exhaust gas obtains a better flow state before entering the turbulence component 2 and the cooling channel 3, creating favorable conditions for subsequent enhanced heat exchange. In some embodiments, the ratio of the cross-sectional area of ​​the first outlet to the cross-sectional area of ​​the first inlet is preferably 1.3:1 to 3.5:1, and can be further 1.5:1 to 2.8:1. This allows the exhaust gas to obtain a more significant expansion and deceleration effect while maintaining low exhaust resistance, improving the heat exchange efficiency of the subsequent cooling channel 3, and balancing engine exhaust performance. The relationship between the axial dimension of the expansion chamber 1 and the cross-sectional areas of the first outlet and the first inlet is not limited here. The axial dimension of the expansion chamber 1 can be comprehensively designed based on factors such as the area ratio of the first inlet to the first outlet, engine exhaust flow rate, exhaust gas temperature, allowable exhaust back pressure, and vehicle installation space. When the area ratio of the first inlet to the first outlet increases, the axial dimension of the expansion chamber 1 can be appropriately increased to allow the exhaust gas to have a more sufficient expansion distance, reduce airflow separation and backflow phenomena, and improve the uniformity of the outlet flow field. When the area ratio is small, the axial dimension can be reduced accordingly to maintain a compact system structure and reduce wall friction loss and exhaust resistance. This allows the exhaust gas to fully complete the expansion, deceleration, and pressure recovery process within the expansion chamber 1, entering the subsequent turbulence assembly 2 and cooling channel 3 in a more uniform and stable flow state, improving the heat exchange efficiency between the exhaust gas and the cooling structure, while also considering cooling performance, exhaust back pressure, and vehicle layout space.In some embodiments, the axial dimension L of the expansion cavity 1 and the equivalent diameter D of the first outlet satisfy 0.8~3.0, and can further be 1.2~2.2. When the area ratio is 1.3~2.0, L / D can be 0.8~1.8; when the area ratio is 2.0~3.5, L / D can be 1.8~3.0. This can reduce local turbulence loss and system back pressure while ensuring sufficient expansion and deceleration of the exhaust gas, thereby improving the heat exchange efficiency and overall cooling effect of the subsequent cooling channel 3.

[0023] Furthermore, in this embodiment, a transition section is provided between the first air inlet and the first air outlet. The transition section extends unequally in the axial direction, which can realize the change of the air outlet direction and the gradual guidance and redistribution of the airflow direction. This allows the airflow to form a certain degree of diffusion and rectification effect during the transition process, thereby reducing the vortex intensity and pressure loss caused by local flow abrupt changes, improving the stability and uniformity of the exhaust flow, and further improving the heat exchange efficiency of the subsequent cooling channel 3.

[0024] The first outlet of the expansion cavity 1 is connected to the cooling channel 3, and the turbulence component 2 is disposed in the cavity inside the cooling channel 3. The connection between the first outlet and the cooling channel 3 is rigid, flange-sealed, or integrally formed, so that the exhaust gas can enter the subsequent enhanced heat exchange area without leakage after passing through the expansion cavity 1. The cooling channel 3 can be configured as an annular or spiral structure. When the cooling channel 3 is configured as an annular structure, the exhaust gas flows continuously along a circumferential closed path in the channel, which significantly extends the flow path, thereby increasing the contact time between the exhaust gas and the inner wall of the channel and improving the convective heat transfer efficiency. When the cooling channel 3 is configured as a spiral structure, the exhaust gas flows circumferentially and gradually advances axially, making the flow path a three-dimensional spiral extension state. This not only further extends the effective heat exchange stroke, but also induces a radial pressure gradient in the exhaust gas under the action of centrifugal force, thereby enhancing the secondary flow and mixing effect of the fluid and improving the overall heat exchange uniformity. The cooling channel 3 has a hollow flow channel structure with a high thermal conductivity material layer on its outer or inner wall, allowing the exhaust gas to continuously exchange heat with the wall during flow, thus achieving continuous cooling. The axial dimension of the cooling channel 3 is not limited here; it can be comprehensively designed based on exhaust gas flow rate, exhaust gas temperature, target cooling temperature, cross-sectional area of ​​the cooling channel 3, number of channels, and overall vehicle installation space. The ratio between the axial dimension of the cooling channel 3 and the axial dimension of the expansion cavity 1 is also not limited. The axial dimension of the cooling channel 3 is smaller than that of the expansion cavity 1, allowing the exhaust gas to first undergo sufficient expansion, deceleration, and pressure recovery within the expansion cavity 1, forming a more uniform and stable flow field before entering the cooling channel 3 for heat exchange, thereby improving the heat exchange efficiency of the cooling channel 3. Simultaneously, the relatively short length of the cooling channel 3 effectively reduces exhaust gas pressure loss along the flow path and system exhaust back pressure, reduces the overall structural size, improves the compactness of the exhaust cooling system and the flexibility of vehicle layout, ensuring both exhaust gas cooling effect and engine exhaust performance.

[0025] The turbulence-disrupting assembly 2 is located in the central region inside the cooling channel 3, with its entire structure positioned at the channel's axis. It is used to further organize and enhance the mixing of the incoming exhaust gas flow. The turbulence-disrupting assembly 2 includes an outer ring, a central hub 210, and multiple turbulence-disrupting blades 220. The outer ring is coaxially connected to the cooling channel 3, forming a stable concentric structure between the baffle assembly 2 and the channel. This prevents eccentric vibration or structural displacement under high-speed exhaust gas impact. The outer ring and the cooling channel 3 can be integrally formed. The central hub 210 and multiple baffle blades 220 can be fixedly connected to the cooling channel 3 via the outer ring, or they can be fixed to the side wall of the cooling channel 3 via the central hub 210 using corresponding connectors. In this embodiment, the central hub 210 and multiple baffle blades 220 can be fixedly connected to the cooling channel 3 via the outer ring, which also serves as the baffle blades 220. An outer fixed support structure forms a stable connection between its inner wall and the outer end of the blades. A central hub 210 is located at the center of the outer ring. Multiple turbulence-inducing blades 220 are arranged circumferentially around the central hub 210. The interior of the central hub 210 can be hollow to reduce weight. One end of each turbulence-inducing blade 220 is fixedly connected to the central hub 210, and the other end is fixedly connected to the outer ring. The outer circumferential surface of the central hub 210 serves as the inner fixed connection base for the multiple turbulence-inducing blades 220, ensuring uniform circumferential distribution of the blades and thus guaranteeing flow field symmetry. The multiple turbulence-inducing blades 220 together form multiple guide channels for the exhaust gas to pass through. The cross-section of the guide channels is tapered or twisted, causing streamline convergence and deflection of the exhaust gas during passage, thereby enhancing local shearing and promoting turbulence generation. After the turbulence is enhanced, the convective heat transfer coefficient between the exhaust gas and the cooling channel wall 3 is significantly improved, thereby enhancing the cooling efficiency. The turbulence-inducing blades 220 can be made of high-temperature resistant alloys. The specific number of deflector blades 220 and the spacing between adjacent deflector blades 220 are not limited here. When the number of deflector blades 220 increases or the spacing between adjacent deflector blades 220 decreases, the number of guide channels can increase and the channel size can decrease, thereby enhancing the shearing and segmentation effect of the exhaust gas, increasing the local turbulence intensity and airflow mixing degree, and thus increasing the convective heat transfer coefficient between the exhaust gas and the cooling channel 3 wall, enhancing the cooling effect. However, if the number is too large or the spacing is too small, it may lead to increased flow resistance and increased local pressure drop, thereby increasing the system exhaust back pressure, which is detrimental to engine exhaust performance. In some embodiments, the number of deflector blades 220 can be 3 to 16, and more specifically 6 to 12, which can control the overall pressure drop while ensuring sufficient deflection intensity, achieving a better balance between heat transfer and exhaust performance. Furthermore, the circumferential spacing between adjacent turbulence blades 220 can be 5°~60°, or even 10°~30°. The included angle with the axis of the central hub 210 as the reference can enable the exhaust gas to form a multi-channel split-convergence-deflection composite flow structure when passing through the turbulence component 2, effectively enhancing the velocity gradient and turbulence pulsation intensity, thereby improving the convective heat transfer coefficient between the exhaust gas and the wall of the cooling channel 3.By setting the number and spacing of the turbulence blades 220, the exhaust gas can form a uniformly distributed multi-stream rotating / deflecting flow within the turbulence assembly 2, enhancing radial and circumferential mixing capabilities. This reduces the local thermal boundary layer thickness while improving overall heat transfer efficiency, and also takes into account system exhaust resistance and structural stability.

[0026] The turbulence blades 220 are inclined along the exhaust gas flow direction to generate swirling flow as the exhaust gas passes through the guide channel. This swirling flow creates a centrifugal force distribution gradient in the exhaust gas during flow, causing high-temperature gas to migrate towards the outer wall and low-temperature gas to flow back towards the center, thereby enhancing radial mixing and temperature homogenization. The swirling flow also extends the effective residence time of the exhaust gas within the cooling channel 3, increasing the heat exchange path between the gas and the cooling wall, thus improving overall heat exchange efficiency. Simultaneously, because the swirling flow disrupts the original laminar boundary layer structure, the boundary layer is continuously sheared, broken, and regenerated, further reducing thermal resistance.

[0027] Furthermore, in this embodiment, Figure 2 A schematic diagram of the temperature control component structure according to an embodiment of the present invention is shown, as follows: Figure 2 As shown, the turbulence assembly 2 also includes a temperature control component 230 and a rotating shaft; the temperature control component 230 and the rotating shaft form a linkage relationship between force transmission and angle adjustment, so that the change in exhaust gas temperature can be directly converted into the mechanical deflection adjustment amount of the turbulence blade 220.

[0028] Each deflector blade 220 corresponds to a set of temperature control components 230 and a rotating shaft. Each deflector blade 220 corresponds to an independent set of temperature control components 230 and rotating shaft structures to achieve control of a single blade, thereby enabling the deflection intensity to be adaptively adjusted according to changes in the local temperature field. Each deflector blade 220 is connected to the central hub 210 via a rotating shaft. The temperature control components 230 adjust the working angle of the deflector blade 220 via the rotating shaft. Each deflector blade 220 is rotatably connected to the central hub 210 via a rotating shaft. The rotating shaft serves as the rotation fulcrum of the blade and also undertakes torque transmission and angle limiting functions, enabling the deflector blade 220 to rotate stably within a preset angle range without structural detachment or displacement. The temperature control component 230 can be connected to the deflector blade 220 or to the drive of the rotating shaft. In one embodiment, the temperature control component acts directly on the body of the deflector blade 220, directly driving the deflector blade 220 to rotate around the rotating shaft through length changes or elastic deformation. This method has a shorter force transmission path and a faster response speed, enabling rapid adjustment of the working angle of the deflector blade 220, and is suitable for operating conditions requiring rapid deflection response. In another embodiment, the temperature control component 230 is connected to the drive of the rotating shaft. By applying torque or axial push-pull force to the rotating shaft, the shaft rotates, thereby indirectly driving the deflector blade 220 to deflect. This method provides a smoother force transmission and avoids deflection deviation or vibration problems caused by uneven force on the deflector blade 220. Furthermore, in this embodiment, the temperature control component 230 is configured as a shape memory alloy spring, which can be directly connected to the hinge point of the deflector blade 220 at its end. The axial deformation generated by the shape memory alloy under temperature action drives the blade rotation; or it can be connected to a drive arm or eccentric structure on the rotating shaft to convert the axial deformation into the rotational torque of the shaft, achieving a mechanical conversion effect of angle amplification or reduction. This allows for a larger change in the blade's working angle within a smaller deformation range, improving the efficiency of temperature control drive. Furthermore, in this embodiment, the working angle range of the deflector blade 220 is 35° to 65°. The working angle refers to the angle between the centerline of the deflector blade 220 and the axial direction of the cooling channel 3, indicating the degree of obstruction and the intensity of the guiding effect of the deflector blade 220 on the axial exhaust flow. At the initial position, the working angle is 35°, making the deflector blade 220 have a smaller angle of attack relative to the axial airflow. At this time, the exhaust gas can pass through the cooling channel 3 more smoothly, with lower flow resistance and lower system exhaust back pressure, which is beneficial for the engine to maintain good exhaust performance under low load or low temperature conditions. When the shape memory alloy spring senses the temperature rise and deforms and elongates, it converts the deformation into a driving torque through the mechanical connection with the rotating shaft, causing the rotating shaft to rotate in a controlled manner, and driving the corresponding deflector blade 220 to rotate synchronously around the rotating shaft, thereby gradually increasing the working angle of the deflector blade 220.As the operating angle gradually increases from 35° to 65°, the shielding and deflection effect of the turbulence blades 220 on the axial exhaust flow gradually intensifies. This splits the originally near-axial airflow into multiple deflected streams, causing significant bending and convergence-diffusion changes in the streamlines. Consequently, a stronger shear layer and vortex structure are induced behind the blades and inside the cooling channel 3, significantly enhancing the local turbulence intensity. This enhanced turbulence can disrupt the stability of the exhaust boundary layer, increasing the convective heat transfer coefficient between the exhaust gas and the wall of the cooling channel 3, thereby improving the overall cooling efficiency. Limiting the operating angle to the range of 35° to 65° avoids excessive deflection of the blades under high-temperature conditions, preventing excessive closure or local blockage of the flow channel. This prevents a sharp increase in system pressure drop and excessive exhaust back pressure, maintaining a reasonable balance between enhanced turbulence and flow resistance. In addition, the shape memory alloy spring has a certain temperature hysteresis characteristic, which makes the deflector blade 220 less prone to frequent shaking during temperature fluctuations. The material of the shape memory alloy spring can be a nickel-titanium based shape memory alloy system, which does not require external power supply and can achieve self-driving adjustment by utilizing the exhaust gas temperature.

[0029] The central hub 210 is shaped like a frustum. The cross-sectional area of ​​the first end of the central hub 210 is smaller than that of the second end. The first end of the central hub 210 is closer to the air outlet, forming a gradually contracting clearance surface on the outer circumference of the central hub 210 towards the air outlet, providing clearance space for the deflection of the spoiler blades 220 around the axis of rotation. The frustum shape creates a tapered clearance space on the outer circumference of the central hub 210 that gradually contracts axially. This ensures that the movement trajectory of the spoiler blades 220 has sufficient space margin when they deflect at large angles, avoiding interference between the blade tips and the outer surface of the hub. It also reduces the risk of aerodynamic drag and structural jamming of the blades under high deflection conditions, thereby improving rotational reliability and dynamic response capability.

[0030] Furthermore, in this embodiment, the central hub 210, the rotating shaft, and the deflector blades 220 are all provided with internal cavities, and the central hub 210, the rotating shaft, and the deflector blades 220 are internally connected; forming a through-type internal gas transport channel, allowing external gas to be continuously transported and distributed within this channel. The center hub 210 is equipped with a hub air inlet, which communicates with the internal cavity of the center hub 210 to introduce outside air. The hub air inlet is located on the end face or side wall of the center hub 210 closest to the external environment. This allows for the induction of a negative pressure effect by utilizing the pressure difference between the external environment and the interior of the cooling channel 3 during vehicle operation or exhaust gas flow, thereby continuously introducing outside air into the internal cavity and forming a stable air supply source. In some embodiments, the hub air inlet can be configured as a single or multiple opening structure to accommodate different flow requirements, and axial or radial air intake methods can be selected depending on the installation location. External gas entering the central hub 210 sequentially enters the internal cavity of the rotating shaft and the internal cavities of each spoiler blade 220 via the internal connecting cavity, achieving a circumferential airflow transport path. The internal cavity of the rotating shaft serves as an intermediate transport channel, used to achieve axial airflow transmission and uniform distribution among the spoiler blades 220, thereby ensuring the relative consistency of the jet volume of each spoiler blade 220 and avoiding uneven turbulence caused by excessive or insufficient jet volume from a single spoiler blade 220. Each spoiler blade 220 is provided with multiple jet holes; the jet holes are connected to the internal cavity of the spoiler blade 220 and are located on the side surface of the spoiler blade 220 facing the inner cavity of the cooling channel 3, allowing the ejected airflow to directly act on the mainstream exhaust gas area, thereby forming a shear mixing effect with the exhaust gas. The jet holes can be uniformly arranged along the blade length or arranged in a gradient along the flow direction, creating a differential distribution of jet intensity near the upstream side and jet intensity near the downstream side, thereby improving the local flow field structure.

[0031] In some implementations, the jet orifice can be configured as a circular orifice, a micro-slit orifice, or an array of micro-holes. The micro-hole structure is beneficial for forming a multi-point scattering flow, improving the mixing efficiency with the main exhaust gas flow. The circular orifice structure is simple to manufacture and has a stable flow rate, making it suitable for basic jet turbulence requirements. The micro-slit orifice structure can form a continuous thin-layer jet in the direction of unit length, which is beneficial for increasing the airflow coverage and enhancing the shearing effect with the main exhaust gas flow. The array of micro-holes structure can disperse a single airflow into multiple discrete micro-jets, allowing the jet gas to enter the exhaust gas flow field in a multi-point, multi-source manner, thereby significantly enhancing the local mixing efficiency and increasing the probability of turbulence generation.

[0032] In some embodiments, the jet orifices are spaced apart along the length of the spoiler blades 220, and the diameter of adjacent jet orifices gradually decreases along the exhaust gas flow direction. This spaced arrangement along the length of the spoiler blades 220 allows for staged release of the injected gas at different axial positions on the blades, thereby creating multiple disturbance sources along the exhaust gas flow path and improving the spatial uniformity of the overall flow field. Furthermore, the diameter of adjacent jet orifices gradually decreases along the exhaust gas flow direction; that is, the jet orifices near the upstream side of the exhaust gas have larger diameters to provide stronger initial disturbance and flow field disruption capabilities, while the jet orifices near the downstream side have gradually smaller diameters, causing a gradual decrease in jet intensity. This avoids local backflow or flow turbulence in the downstream region due to excessive jet intensity, achieving gradual control of the disturbance intensity and creating a gradient distribution structure of strong, medium, and weak disturbances in the exhaust gas field along the axial direction.

[0033] In some embodiments, the jet direction of the jet orifice is set at a preset angle relative to the surface normal direction of the baffle blade 220, so that the external gas enters the cooling channel 3 along the tangential component to form an entrained flow field. The preset angle can be in the range of 10° to 60°, so that the jet flow has both radial and tangential components. At a smaller angle, the jet mainly penetrates the mainstream, which is beneficial to enhance the local penetration and mixing ability; at a larger angle, the jet mainly slides and rotates along the wall, which is beneficial to enhance the circumferential vortex structure and wall shear effect. By setting the preset angle, the external gas can form a stable entrained flow field structure after entering the cooling channel 3, and form a multi-scale, multi-directional composite mixing process with the exhaust gas mainstream. By setting the jet orifice diameter and the preset angle, the local flow field can be finely controlled, thereby further superimposing the jet-induced disturbance effect on the mechanical disturbance of the baffle blade 220, significantly enhancing the exhaust gas turbulence intensity and boundary layer destruction ability, improving the convective heat transfer coefficient between the exhaust gas and the wall of the cooling channel 3, and ultimately improving the cooling efficiency. By connecting the hub air intake to the injection hole, outside air can enter the cold zone flow channel without the need for an additional power unit, relying on the ejection effect generated by the pressure difference induced by the hub air intake, and participate in the exhaust gas mixing process. This superimposes the gas jet turbulence effect on the mechanical turbulence, improves the convective heat transfer coefficient, and thus improves the overall cooling efficiency.

[0034] Furthermore, in this embodiment, the inner wall of the expansion cavity 1 is provided with several flow-guiding protrusions, which are arranged at intervals along the circumference of the expansion cavity 1. This introduces a controllable circumferential velocity component into the original axial expansion flow, causing the exhaust gas to generate rotational motion simultaneously during the expansion and deceleration process. Through this arrangement, the flow-guiding protrusions can exert a continuous tangential traction effect on the boundary layer fluid near the wall, causing the boundary layer, which originally developed axially, to undergo circumferential deflection and redistribution, thereby delaying the boundary layer separation trend and reducing the probability of forming a large-scale backflow zone. The cross-section of the flow-guiding protrusions is streamlined or semi-elliptical, with a circular arc transition on the upstream side and a gradually tapering slope on the downstream side. The streamlined cross-section allows for a smooth pressure gradient change in the exhaust gas upon contact with the guide protrusion, reducing local impact losses and eddy shedding intensity, thus maintaining the flow in an adherent state as much as possible. The semi-elliptical cross-section, through a continuously varying radius of curvature, allows the exhaust gas to gradually change direction during its flow, avoiding local flow separation caused by abrupt geometric changes and improving overall flow stability. The upstream side of the guide protrusion is designed with a circular arc transition structure, allowing the exhaust gas to gradually change its flow direction upon entering the effective region of the guide protrusion. This reduces energy losses caused by abrupt changes in local velocity gradients and minimizes the generation of impact eddies, enabling the boundary layer to smoothly adhere to the structure surface and develop. The downstream side is designed with a tapering slope structure, allowing the exhaust gas to gradually recover its flow space after bypassing the guide protrusion, thus forming a slowly expanding wake region on the downstream side. This reduces exhaust gas velocity and impact intensity while improving flow field uniformity and energy distribution uniformity.

[0035] This embodiment, by setting up an expansion cavity 1, causes a sudden expansion of the cross-section of the exhaust gas upon entering the system, thereby reducing the airflow velocity and extending the residence time within the system. This provides more sufficient heat exchange conditions for the heat from the exhaust gas to diffuse to the outside, contributing to the initial cooling effect. Furthermore, a turbulence assembly 2, consisting of an outer ring, a central hub 210, and multiple turbulence blades 220, is installed inside the cooling channel 3. This divides the exhaust gas into multiple guiding channels, allowing the airflow to fully contact the channel wall and the turbulence structure during its flow, significantly improving convective heat transfer efficiency. Simultaneously, the turbulence blades 220 are arranged obliquely along the exhaust gas flow direction, creating a swirling effect as the exhaust gas passes through the guiding channels. This enhances the turbulence intensity and mixing degree, promoting heat exchange between high-temperature gases and between the gas and the wall, further improving the cooling capacity. In addition, the outer ring, central hub 210, and turbulence blades 220 form a stable overall structure, ensuring the turbulence effect while maintaining channel continuity and avoiding the generation of local flow dead zones. With a compact overall structure, it can achieve efficient exhaust gas cooling and is suitable for the compact design requirements of automotive exhaust systems.

[0036] Example 2 An exhaust gas treatment assembly, Figure 3 A schematic diagram of the overall structure of an exhaust gas treatment assembly according to an embodiment of the present invention is shown, as follows: Figure 3 As shown, the exhaust gas treatment assembly includes the aforementioned automotive exhaust cooling system, and also includes: a first exhaust tailpipe 4, a rear muffler 5, a second exhaust tailpipe 6, an active valve, and an active valve drive-by-wire system 7. The first exhaust tailpipe 4 is connected to the rear muffler 5. The first exhaust tailpipe 4 guides the high-temperature exhaust gas from the engine to the rear muffler 5, allowing the exhaust gas to first enter the silencing treatment stage to reduce exhaust pulsation noise and high-frequency airflow noise. The rear muffler 5 performs multi-stage silencing treatment on the exhaust gas. Through expansion chambers, perforated pipes, and sound-absorbing structures, it attenuates the pressure waves in the exhaust gas, enabling the exhaust gas to achieve sound energy reduction and flow homogenization before entering the subsequent cooling system, thereby reducing the impact of airflow pulsation on subsequent structures. The rear muffler 5 is connected to the vehicle's exhaust cooling system through the second exhaust tailpipe 6. The rear muffler 5, after silencing treatment, enters the cooling treatment stage. During this process, the temperature and pressure fluctuations of the exhaust gas are reduced to a certain extent, which helps improve the working stability and heat exchange efficiency of the subsequent expansion chamber 1 and turbulence assembly 2. The active valve and the active valve wired control system 7 are installed at the second exhaust tailpipe. The active valve is used to adjust the opening of the exhaust channel or the switching state of the exhaust path in the second exhaust tailpipe according to the control signal output by the active valve wired control system 7, thereby realizing active control of the exhaust gas flow path and flow distribution.

[0037] The active valve drive-by-wire system 7 acquires the total amount of gas discharged by the vehicle's exhaust cooling system during the previous preset time period and generates an active valve control signal by combining this data with the current engine operating conditions and the corresponding total exhaust volume demand. The active valve drive-by-wire system 7 acquires the total amount of gas discharged by the vehicle's exhaust cooling system in real time during the previous preset time period, such as the past 5-10 seconds. This total amount of gas discharged reflects the thermal accumulation state of the exhaust system and the current exhaust inertia. Simultaneously, it acquires the current engine operating conditions, such as engine speed, throttle opening, and load, and the corresponding total exhaust volume demand value. This total exhaust volume demand value serves as a feedforward signal for predicting future flow trends.

[0038] The active valve wired control system 7 performs a weighted calculation or threshold comparison between the acquired total discharged gas volume and the total exhaust volume demand value to determine the adjustment strategy of the active valve: When the total amount of gas discharged in the previous time period is small and the current total exhaust volume demand is low, i.e., both are below the corresponding set thresholds, the exhaust gas is determined to be in a low-load condition. At this time, the active valve drive system 7 outputs a low-load control signal, driving the active valve to reduce the opening of its exhaust channel to a preset first opening ratio, such as 15%-30%. Under low-load conditions, the exhaust gas flow rate is slow. By reducing the opening of the active valve, the exhaust back pressure can be artificially increased appropriately, prolonging the residence time of the exhaust gas in the expansion chamber 1. This allows the temperature control component in the turbulence assembly 2 to have more time to sense the exhaust gas temperature, thereby driving the turbulence blades 220 to perform adaptive angle adjustment, avoiding local heat accumulation caused by insufficient heat exchange at low flow rates, and ensuring cooling efficiency under low load.

[0039] When either the total amount of gas discharged in the previous time period or the current total exhaust volume demand exceeds a set threshold, the system determines that the exhaust gas has entered a medium-to-high load condition. At this time, the active valve drive system 7 outputs a high-load control signal, driving the active valve to rapidly increase its opening to the second opening ratio, for example, 70%-100%. Under medium-to-high load conditions, this ensures smooth exhaust to reduce back pressure and prevent damage to engine power. The larger opening allows high-flow exhaust gas to pass through quickly, while the high-velocity airflow directly impacts the deflector blades 220, which have deflected due to temperature increases. Through intense turbulent mixing, the high-flow exhaust gas is rapidly cooled in a very short time.

[0040] Through the above-mentioned adjustments of the active valve drive system 7, excellent exhaust cooling effect and noise control level can be maintained under all operating conditions from idle to high speed.

[0041] It should be understood that the specific embodiments described above are merely illustrative or explanatory of the principles of the invention and do not constitute a limitation thereof. Therefore, any modifications, equivalent substitutions, improvements, etc., made without departing from the spirit and scope of the invention should be included within the protection scope of the invention. Furthermore, the appended claims are intended to cover all variations and modifications falling within the scope and boundaries of the appended claims, or equivalent forms of such scope and boundaries.

[0042] The above description does not provide detailed explanations of the technical aspects of each layer's patterning and etching. However, those skilled in the art should understand that various methods existing in the prior art can be used to form layers and regions of the desired shape. Furthermore, to form the same structure, those skilled in the art can also design methods that are not entirely identical to those described above.

[0043] The present invention has been described above with reference to embodiments thereof. However, these embodiments are merely illustrative and not intended to limit the scope of the invention. The scope of the invention is defined by the appended claims and their equivalents. Various substitutions and modifications can be made by those skilled in the art without departing from the scope of the invention, and all such substitutions and modifications should fall within the scope of the invention.

[0044] Although embodiments of the present invention have been described in detail, it should be understood that various changes, substitutions, and modifications can be made to the embodiments of the present invention without departing from the spirit and scope of the invention.

[0045] Obviously, the above embodiments are merely illustrative examples for clear explanation and are not intended to limit the implementation. Those skilled in the art will recognize that other variations or modifications can be made based on the above description. It is neither necessary nor possible to exhaustively list all possible implementations here. However, obvious variations or modifications derived therefrom are still within the scope of protection of this invention.

Claims

1. A vehicle exhaust cooling system, characterized in that, include: Expansion chamber, turbulence-inducing components, and cooling channels; The expansion cavity includes a first air inlet and a first air outlet, wherein the cross-sectional area of ​​the first air outlet is larger than the cross-sectional area of ​​the first air inlet. The first air outlet of the expansion cavity is connected to the cooling channel, and the turbulence component is disposed in the cavity inside the cooling channel; The aerodynamic component includes an outer ring, a central hub, and multiple aerodynamic blades; The outer ring is coaxially connected to the cooling channel, the central hub is located at the center of the outer ring, and a plurality of the baffles are arranged at intervals along the circumference of the central hub. One end of each baffle is fixedly connected to the central hub, and the other end of each baffle is fixedly connected to the outer ring. The plurality of baffles together form a plurality of guide channels for the exhaust gas to pass through. The turbulence blades are inclined along the exhaust gas flow direction so that the exhaust gas will generate swirling flow when it passes through the guide channel.

2. The automotive exhaust cooling system according to claim 1, characterized in that, The turbulence-disrupting component also includes: a temperature control component and a rotating shaft; Each of the deflection blades corresponds to a set of temperature control components and a rotating shaft. Each of the deflection blades is connected to the central hub through the rotating shaft. The temperature control components adjust the working angle of the deflection blades through the rotating shaft. The central hub is configured as a frustum shape, with the cross-sectional area of ​​the first end of the central hub being smaller than that of the second end of the central hub. The first end of the central hub is the end closest to the air outlet, so that the outer circumferential surface of the central hub forms a clearance surface that gradually contracts towards the air outlet, providing clearance space for the deflection of the spoiler blades around the rotating axis.

3. The automotive exhaust cooling system according to claim 2, characterized in that, The working angle range of the baffle blade is 35° to 65°, and the temperature control component is a memory alloy spring. When the shape memory alloy spring senses an increase in temperature and deforms and elongates, it drives the corresponding spoiler blades to rotate via the rotating shaft, increasing the working angle.

4. The automotive exhaust cooling system according to claim 2, characterized in that, The central hub, rotating shaft, and spoiler blades are all provided with internal cavities, and the central hub, rotating shaft, and spoiler blades are internally connected; The central hub is provided with a hub air inlet, and each of the deflector blades is provided with multiple jet holes; The hub air intake is connected to the outside atmosphere. Outside air enters the interior of the central hub, shaft and spoiler blades through the hub air intake and is ejected through the jet hole.

5. The automotive exhaust cooling system according to claim 4, characterized in that, The hub air inlet is located on the end face or side wall of the central hub that is close to the outside atmosphere, and communicates with the internal cavity of the central hub. The jet hole is disposed on the outer surface of the baffle blade facing the inner cavity of the cooling channel and communicates with the inner cavity of the baffle blade.

6. The automotive exhaust cooling system according to claim 5, characterized in that, The jet holes are arranged at intervals along the length of the deflector blades, and the diameter of adjacent jet holes gradually decreases along the exhaust gas flow direction.

7. The automotive exhaust cooling system according to claim 5, characterized in that, The jet direction of the jet orifice is set at a preset angle relative to the surface normal direction of the turbulence blade, so that the external gas enters the cooling channel along the tangential component to form an ejector flow field.

8. The automotive exhaust cooling system according to claim 1, characterized in that, The inner wall of the expansion cavity is provided with a plurality of flow-guiding protrusions, which are arranged at intervals along the circumference of the expansion cavity.

9. The automotive exhaust cooling system according to claim 8, characterized in that, The cross-section of the flow-guiding protrusion is streamlined or semi-elliptical, with the front side of the flow-guiding protrusion having a circular arc transition and the back side having a gradually tapering slope.

10. An exhaust gas treatment assembly, characterized in that, The exhaust gas treatment assembly includes the automotive exhaust cooling system as described in any one of claims 1-9, and the exhaust gas treatment assembly further includes: a first exhaust tailpipe, a rear muffler, a second exhaust tailpipe, an active valve, and an active valve drive-by-wire system. The first exhaust tailpipe is connected to the rear muffler, and the rear muffler is connected to the vehicle exhaust cooling system via the second exhaust tailpipe. The active valve and the active valve drive-by-wire system are located at the second exhaust tailpipe. The active valve is used to adjust the exhaust switching in the second exhaust tailpipe according to the control signal of the active valve wire control system.

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