Mixing device, engine and vehicle

Abstract

The invention provides a mixing device, an engine and a vehicle, the mixing device comprises an inner pipe, an outer pipe and a flow guide part, the inner pipe is suitable for circulating a first fluid, the outer pipe is sleeved outside the inner pipe, a gap is formed between the outer pipe and the inner pipe, the gap is suitable for circulating a second fluid, and the flow guide part is arranged in the inner pipe or between the outer pipe and the inner pipe. The first fluid flows in from the inner pipe, the second fluid flows in from the gap between the inner pipe and the outer pipe, the first fluid is mixed with the second fluid after flowing out of the inner pipe, the first fluid and the second fluid are fully mixed by arranging the flow guide piece, and the mixing effect is good.

Description

Technical Field

[0001] The present invention relates to the field of engines, and in particular to a mixing device, an engine and a vehicle. Background Art

[0002] Exhaust gas from automobile engines is typically hot. If it is discharged directly outside the vehicle without cooling, it could ignite flammable materials on the road (such as hay, straw, and catkins), potentially causing a fire. Existing technologies can reduce the temperature of engine exhaust by mixing it with cooling air. However, this simple mixing of the exhaust gas and cooling air within a single chamber results in poor mixing and, consequently, limited exhaust gas cooling, creating a need for improvement. Summary of the Invention

[0003] The present invention aims to solve at least one of the technical problems in the prior art. To this end, the present invention provides a mixing device that can fully mix two fluids with good mixing effect.

[0004] The mixing device of the present invention is used to mix a first fluid and a second fluid. The mixing device includes: an inner tube, suitable for circulating the first fluid; an outer tube, the outer tube is arranged outside the inner tube and a gap is formed between the two, and the gap is suitable for circulating the second fluid; and a flow guide member, the flow guide member is arranged inside the inner tube or between the outer tube and the inner tube.

[0005] Furthermore, the flow guide includes a plurality of vertebrae, the plurality of vertebrae are arranged between the outer tube and the inner tube, and the plurality of vertebrae are distributed along the circumference of the inner tube.

[0006] Furthermore, the tip of the cone faces the air intake direction.

[0007] Furthermore, the vertebral body is a triangular pyramid, the inner surface of the triangular pyramid is an arc-shaped surface, the inner surface of the triangular pyramid fits the outer surface of the inner tube, and the outer top of the triangular pyramid contacts the inner surface of the outer tube.

[0008] Furthermore, the guide member includes a plurality of first guide plates, which are arranged between the outer tube and the inner tube. The plurality of first guide plates are arranged in a wave shape along the circumference of the inner tube, and are arranged in a V shape between two adjacent first guide plates.

[0009] Furthermore, the guide member includes a plurality of second guide plates, which are arranged between the outer tube and the inner tube, and are arranged along the circumference of the inner tube. The second guide plates extend axially along the inner tube and bend toward the circumference of the inner tube.

[0010] Furthermore, the guide member includes a plurality of third guide vanes, and the plurality of third guide vanes are distributed in the inner tube along the circumference of the inner tube.

[0011] Furthermore, the inner tube and the outer tube are coaxially arranged, the gap between the inner tube and the outer tube is an annular gap, and the ratio of the width of the annular gap to the inner diameter of the inner tube is between 0.1-0.15.

[0012] Furthermore, the length of the inner tube is smaller than that of the outer tube, the air inlet end of the inner tube is flush with the air inlet end of the outer tube, the air outlet end of the inner tube is located inside the outer tube, and multiple vertebrae are arranged at the air outlet end of the inner tube, and the tips of the vertebrae are facing the air inlet end of the inner tube.

[0013] Furthermore, the air outlet end of the inner tube is located inside the outer tube, and a spoiler is provided between the air outlet end of the inner tube and the air outlet end of the outer tube.

[0014] Furthermore, the spoiler is an annular member, and the annular member is arranged in the outer tube.

[0015] Furthermore, there are two annular members, and the two annular members are arranged side by side along the axial direction of the outer tube.

[0016] Furthermore, the annular member is provided with an annular inner convex portion protruding toward the center direction of the outer tube.

[0017] Furthermore, the spoiler includes a plurality of protrusions, and the plurality of protrusions protrude from the inner wall of the outer tube toward the center of the outer tube.

[0018] Furthermore, the protrusion is a triangular protrusion.

[0019] The present invention also provides an engine comprising the above-mentioned mixing device.

[0020] The present invention provides a vehicle comprising the above-mentioned hybrid device or engine.

[0021] Beneficial effects: The mixing device of the present invention includes an inner tube and an outer tube, which are sleeved together to form a gap. During operation, a first fluid flows in from the inner tube, and a second fluid flows in from the gap between the inner tube and the outer tube. After the first fluid flows out of the inner tube, it mixes with the second fluid. By setting a flow guide, the first fluid and the second fluid are fully mixed, and the mixing effect is good.

[0022] When the mixing device of the present application is used in a vehicle engine, the first fluid can be high-temperature engine exhaust gas, and the second fluid can be low-temperature external air. The mixing device can fully mix the engine exhaust gas and the external air, with good mixing effect and good exhaust gas cooling effect. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 is a disassembled schematic diagram of a mixing device according to one embodiment of the present invention; Figure 2 is a schematic cross-sectional view of a mixing device according to one embodiment of the present invention; Figure 3 is a disassembled schematic diagram of a mixing device according to one embodiment of the present invention; Figure 4 is a disassembled schematic diagram of a mixing device according to one embodiment of the present invention; Figure 5 is a disassembled schematic diagram of a mixing device according to one embodiment of the present invention; Figure 6 is a schematic diagram of a third guide vane according to an embodiment of the present invention; Figure 7 is a schematic cross-sectional view of a mixing device at the gas outlet end of an inner tube according to an embodiment of the present invention; Figure 8 is a schematic diagram of a vehicle according to an embodiment of the present invention. DETAILED DESCRIPTION

[0024] The embodiments of the present invention are described in detail below. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain the present invention, and should not be understood as limiting the present invention.

[0025] In the description of the present invention, it should be understood that the terms "upper", "lower", "left", "right", "front", "back", etc., indicating directions or positional relationships, are based on the directions or positional relationships shown in the accompanying drawings. They are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific direction and be constructed and operated in a specific direction. Therefore, they cannot be understood as limiting the present invention. In addition, features defined as "first" and "second" may explicitly or implicitly include one or more of such features. In the description of the present invention, unless otherwise specified, "plurality" means two or more.

[0026] In the description of the present invention, it should be noted that, unless otherwise expressly specified or limited, the terms "installed," "disposed," "connected," and "connected" should be understood in a broad sense. For example, they may refer to fixed connections, detachable connections, or integral connections; mechanical connections or electrical connections; direct connections or indirect connections through an intermediate medium; and internal connections between two components. Those skilled in the art will understand the specific meanings of the above terms in the present invention based on specific circumstances.

[0027] The following is combined with Figure 1-8 A hybrid device, an engine, and a vehicle according to embodiments of the present invention are described.

[0028] A mixing device 100 according to one embodiment of the present invention is used to mix a first fluid and a second fluid. The mixing device 100 includes an inner tube 10, an outer tube 20, and a flow guide. The inner tube 10 is suitable for circulating the first fluid. The outer tube 20 is arranged outside the inner tube 10 to form a gap between the inner tube 10 and the outer tube 20, which is suitable for circulating the second fluid. The flow guide is arranged inside the inner tube 10 or between the outer tube 20 and the inner tube 10. When the flow guide is arranged inside the inner tube 10, the flow guide can guide the first fluid flowing in the inner tube 10, so that the first fluid flows out of the inner tube 10 and is fully mixed with the second fluid, achieving a better mixing effect. When the flow guide is arranged between the outer tube 20 and the inner tube 10 (i.e., in the gap), the flow guide can guide the second fluid flowing between the outer tube 20 and the inner tube 10, so that the second fluid is fully mixed with the first fluid flowing out of the inner tube 10, achieving a better mixing effect.

[0029] When the mixing device 100 according to an embodiment of the present invention is used in an engine exhaust system, one of the first fluid and the second fluid can be exhaust gas (tail gas) emitted by the engine, and the other of the first fluid and the second fluid can be external air. For example, the first fluid can be high-temperature engine exhaust gas, and the second fluid can be low-temperature external air. By thoroughly mixing the exhaust gas and external air in the mixing device 100, the exhaust gas can be fully cooled, significantly reducing its temperature. The mixed gas is then discharged outside the vehicle. Due to its lower temperature, the mixed gas discharged outside the vehicle will not ignite flammable materials on the road (such as hay, straw, catkins, etc.), thereby avoiding the risk of fire. By providing an annular flow channel, the low-temperature external air can be evenly distributed within the annular flow channel, that is, evenly distributed circumferentially outside the inner tube 10, to facilitate better heat exchange and mixing.

[0030] The inner tube 10 can be a circular tube, a square tube or a tube of other shapes, and the outer tube 20 can be a circular tube, a square tube or a tube of other shapes. The following embodiments are described with the inner tube 10 and the outer tube 20 being circular tubes.

[0031] When both inner tube 10 and outer tube 20 are circular tubes, they are coaxially arranged. The gap between them is an annular gap. The annular gap extends axially along inner tube 10, forming an annular flow channel for circulating the second fluid. The ratio of the width of the annular gap to the inner diameter of inner tube 10 is between 0.1 and 0.15. The width of the annular gap refers to the radial width of inner tube 10, i.e., the distance from the outer surface of inner tube 10 to the inner surface of outer tube 20 along the radial direction of inner tube 10.

[0032] In one embodiment, the length of the inner tube 10 is shorter than that of the outer tube 20. The air inlet end A of the inner tube 10 is flush with the air inlet end B of the outer tube 20. The air outlet end C of the inner tube 10 is located inside the outer tube 20, that is, there is a certain distance between the air outlet end C of the inner tube 10 and the air outlet end D of the outer tube 20. The space between the air outlet ends of the inner tube 10 and the outer tube 20 of the outer tube 20 forms a mixing space, and the first fluid and the second fluid can be fully mixed in this mixing space.

[0033] The length between the outlet end of inner tube 10 and the outlet end of outer tube 20 is 1.5-5 times the inner diameter of inner tube 10 to ensure adequate gas mixing and heat exchange. For low-flow exhaust gas scenarios, the mixing space can be set to a longer length of 5 times the inner diameter of inner tube 10, extending the mixing time and improving the cooling effect. For compact exhaust systems, the mixing space can be set to a shorter length of 1.5 times the inner diameter of inner tube 10 to increase the flow rate of cold air (outside air) to compensate for the lack of mixing time.

[0034] In one embodiment, the guide member includes a plurality of cones 30, which are arranged between the outer tube 20 and the inner tube 10, and are distributed along the circumference of the inner tube 10. The tips 32 of the cones 30 face the air intake direction. Figure 1 shown.

[0035] Specifically, the cone 30 is a triangular pyramid with an arcuate inner surface. The inner surface of the cone 30 is aligned with the outer surface of the inner tube 10, and the outer top 33 of the cone 30 contacts the inner surface of the outer tube 20. The cone 30 can be welded to the inner tube 10, and the cone 30 can also be welded to the outer tube 20, achieving fixation through welding. Multiple cones 30 are arranged at the outlet end of the inner tube 10, with the tips 32 of the cones 30 facing the air inlet direction.

[0036] By providing a plurality of vertebrae 30 with their pointed ends 32 facing the air intake direction, a plurality of air flow channels gradually decreasing in size along the air flow direction are formed between adjacent vertebrae 30, thereby generating a Venturi effect, thereby increasing the external air velocity to above the critical Reynolds number, forming a high-speed turbulent jet, and allowing the external air to be fully mixed with the engine exhaust gas after entering the mixing space, thereby enhancing the mixing effect.

[0037] The end of the cone 30 (i.e., the end opposite to the tip 32) forms a nozzle-like structure, which can expand the spatial diffusion range of the ejected airflow. This design enables the cold airflow to have a stronger ability to draw in the surrounding high-temperature gas, further improving the mixing effect.

[0038] The number of the vertebral bodies 30 is not limited and can be 6, 8, 12, etc. The vertebral bodies 30 are made of high temperature resistant metal material.

[0039] At the end of the cone 30 (i.e., the end opposite to the tip 32), the two adjacent cones 30 and the wall of the outer tube 20 form a fan-shaped nozzle outlet. Figure 7 As shown, the fan nozzle H's apex angle (fan angle) can be adjusted between 30° and 150°. A smaller fan nozzle angle (e.g., 30°) further accelerates the cold air flow rate and enhances mixing efficiency, making it suitable for standard exhaust pipes. A larger angle (e.g., 150°) reduces flow resistance and particle retention, making it suitable for highly dusty exhaust environments. The apex angle should be optimized based on fluid dynamics parameters such as the Reynolds number and set according to specific scenario requirements. When the cold and hot air flows meet in the mixing space, intense mixing and heat exchange occur.

[0040] In one embodiment, the deflector includes a plurality of first deflectors 40 disposed between the outer tube 20 and the inner tube 10. The first deflectors 40 are arranged in a wavy pattern along the circumference of the inner tube 10, with adjacent first deflectors 40 arranged in a V-shape. A gap is provided between the proximal ends of adjacent first deflectors 40. The number of first deflectors 40 can be between 6 and 12, and the angle between adjacent first deflectors 40 can be between 30 and 150 degrees.

[0041] In one embodiment, the guide member includes a plurality of second guide plates 50, which are disposed between the outer tube 20 and the inner tube 10 and arranged along the circumference of the inner tube 10. The second guide plates 50 extend along the axial direction of the inner tube 10 and bend toward the circumference of the inner tube 10. Figure 4 As shown, it should be noted that the second guide vane 50 extends axially along the inner tube 10 and curves circumferentially. This merely describes the shape of the second guide vane 50. Because the second guide vane 50 extends axially along the inner tube 10 and curves circumferentially, it forms a curved surface. This can induce rotation in the airflow (external air) to enhance subsequent mixing. The curvature of the second guide vane 50 gradually increases along the flow direction of the airflow.

[0042] The surface of the second guide vane 50 is a curved surface, and the curvature can be expressed by the radian of the surface. The radian of the surface is different at different positions, and the radian of the surface gradually increases along the flow direction of the airflow. For example, the radian of the surface gradually increases from 15 degrees to 45 degrees. Increasing the radian can improve the angular momentum conversion efficiency and enhance the swirl intensity. The ratio of the axial length of the second guide vane 50 to the inner diameter of the inner tube 10 is between 0.3 and 0.7. The number of second guide vanes 50 can be between 6 and 12. Increasing to 12 can improve the circumferential flow uniformity and is suitable for working conditions with large engine exhaust flow; if the exhaust back pressure does not meet the engineering requirements, the number of guide vanes can be reduced to 6.

[0043] In one embodiment, the deflector includes a plurality of third deflectors 60 distributed within the inner tube 10 along its circumference. The surfaces of the third deflectors 60 are curved. For each third deflector 60, the curvature of the curved surface varies across multiple cross-sections perpendicular to the axial direction of the inner tube 10. The curvature of the curved surface gradually increases or decreases along the axial direction of the inner tube 10. The third deflectors 60 can induce rotation in the airflow (exhaust gas), enhancing the mixing effect laterally.

[0044] In one embodiment, the length of the inner tube 10 is shorter than that of the outer tube 20, and the air inlet end of the inner tube 10 is flush with the air inlet end of the outer tube 20. The air outlet end of the inner tube 10 is located inside the outer tube 20, and a spoiler is provided between the air outlet ends of the inner tube 10 and the outer tube 20. The spoiler is an annular member 70, which is disposed inside the outer tube 20 and welded to the outer tube 20 for secure connection. There may be two annular members 70, which are arranged side by side along the axial direction of the outer tube 20.

[0045] The annular member 70 is provided with an annular inner convex portion 72 that protrudes toward the center of the outer tube 20. The longitudinal cross-sectional profile of the annular inner convex portion 72 can be a sine wave, where the longitudinal cross-section refers to a cross-section passing through the central axis of the outer tube 20. The spoiler can disturb the flow of gas to enhance the mixing effect.

[0046] The present invention provides a wavy sinusoidal corrugated structure in the mixing space. This structure creates alternating pressure changes in the direction of gas flow through surface fluctuations. When a high-speed airflow flows over the corrugated surface, the local pressure generated by the concave area of the corrugation decreases, inducing the formation of small vortices, while the convex area accelerates the airflow and increases the disorder of the airflow. This periodic disturbance acts on both the cold and hot airflows simultaneously, effectively destroying the smooth boundary layer during the heat transfer process, and increasing the heat exchange contact area through a large number of eddies, achieving a step-by-step increase in the heat transfer coefficient.

[0047] In one embodiment, the spoiler includes a plurality of protrusions 80, which are provided on the inner wall of the outer tube 20. Specifically, the protrusions 80 are triangular protrusions, and the vertex angle of the triangular protrusions may be 10 degrees.

[0048] As air flows, it strikes the slope of the triangular protrusion, generating a centripetal velocity component that disrupts the smooth boundary layer and further enhances the mixing efficiency of the hot and cold streams in the direct-swirl mixing space. By varying the cross-sectional shape of the protrusion 80 (e.g., fan-shaped, trapezoidal, or semicircular), the local turbulence intensity and pressure loss ratio can be tailored to meet engineering requirements under varying exhaust backpressure constraints. For example, a prismatic protrusion 80 is suitable for high exhaust flow conditions, while a cylindrical protrusion 80 is more suitable for low exhaust flow conditions.

[0049] An engine 1000 according to an embodiment of the present invention includes the above-mentioned mixing device 100. The mixing device 100 can be installed at the tail end of the exhaust system of the engine 1000, or can be integrated with the exhaust system of the engine 1000, so that the engine exhaust can be fully cooled to avoid igniting flammable materials on the road.

[0050] A vehicle 10000 according to an embodiment of the present invention includes the aforementioned hybrid device 100 or the aforementioned engine 1000 .

[0051] Throughout this specification, reference to terms such as "embodiment" or "example" indicates that the specific features, structures, materials, or characteristics described in conjunction with that embodiment or example are included in at least one embodiment or example of the present invention. In this specification, schematic representations of these terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples.

[0052] While embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions, and variations may be made to the embodiments without departing from the principles and spirit of the invention, and that the scope of the invention is defined by the claims and their equivalents.

Claims

1. A mixing device for mixing a first fluid and a second fluid, characterized in that: The mixing device comprises: an inner tube adapted to flow a first fluid; an outer tube, the outer tube being sleeved outside the inner tube to form a gap therebetween, the gap being suitable for the flow of a second fluid; A flow guide is provided inside the inner tube or between the outer tube and the inner tube.

2. The mixing device according to claim 1, wherein The flow guide comprises a plurality of vertebrae, which are arranged between the outer tube and the inner tube and are distributed along the circumference of the inner tube.

3. The mixing device according to claim 2, characterized in that The pointed end of the cone faces the air intake direction.

4. The mixing device according to claim 2, wherein The vertebral body is a triangular pyramid, the inner surface of the triangular pyramid is an arc-shaped surface, the inner surface of the triangular pyramid fits the outer surface of the inner tube, and the outer top of the triangular pyramid contacts the inner surface of the outer tube.

5. The mixing device according to claim 1, wherein The guide member includes a plurality of first guide plates, which are arranged between the outer tube and the inner tube. The plurality of first guide plates are arranged in a wave shape along the circumference of the inner tube, and are arranged in a V shape between two adjacent first guide plates.

6. The mixing device according to claim 1, wherein The guide member includes a plurality of second guide plates, which are arranged between the outer tube and the inner tube, and are arranged along the circumference of the inner tube. The second guide plates extend along the axial direction of the inner tube and bend toward the circumference of the inner tube.

7. The mixing device according to claim 1, wherein The guide member includes a plurality of third guide vanes, and the plurality of third guide vanes are distributed in the inner tube along the circumference of the inner tube.

8. The mixing device according to claim 1, wherein The inner tube and the outer tube are coaxially arranged, the gap between the inner tube and the outer tube is an annular gap, and the ratio of the width of the annular gap to the inner diameter of the inner tube is between 0.1-0.

15.

9. The mixing device according to claim 2, wherein The length of the inner tube is smaller than that of the outer tube, the air inlet end of the inner tube is flush with the air inlet end of the outer tube, the air outlet end of the inner tube is located inside the outer tube, and a plurality of vertebral bodies are arranged at the air outlet end of the inner tube, with the pointed ends of the vertebral bodies facing the air inlet end of the inner tube.

10. The mixing device according to claim 1, wherein The air outlet end of the inner tube is located inside the outer tube, and a spoiler is provided between the air outlet end of the inner tube and the air outlet end of the outer tube.

11. The mixing device according to claim 10, wherein The spoiler is an annular member, and the annular member is arranged in the outer tube.

12. The mixing device according to claim 11, wherein There are two annular members, and the two annular members are arranged side by side along the axial direction of the outer tube.

13. The mixing device according to claim 11, wherein The annular member is provided with an annular inner convex portion which protrudes toward the center direction of the outer tube.

14. The mixing device according to claim 10, wherein The spoiler includes a plurality of protrusions protruding from an inner wall of the outer tube toward a center of the outer tube.

15. The mixing device according to claim 14, wherein The raised portion is a triangular raised portion.

16. An engine, characterized in that: The mixing device comprises the mixing device according to any one of claims 1 to 15.

17. A vehicle, characterized in that: The invention comprises the mixing device according to any one of claims 1 to 15 or the engine according to claim 16.

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