A bridge pier drag reduction device based on Venturi bubble generator

Abstract

The invention discloses a bridge pier drag reduction device based on a venturi bubble generator, comprising a venturi bubble generator group, a bracket, a venturi bubble generator and an air introduction pipe connected to the venturi bubble generator. The device is characterized in that the bottom of the bracket is implanted in the riverbed of the river bottom, the bracket can stably support the venturi bubble generator group, the venturi bubble generator group is supported by the bracket and placed in the water, and is evenly arranged in the upstream water flow of the bridge pier, the venturi bubble generator can generate a bubble group by the impact of the water flow, so that a layer of micro-bubble and water mixed layer is generated on the contact surface of the bridge pier impacted by the water flow, and this layer of micro-bubble and water mixed layer can reduce the flow resistance of the water flow through the bridge pier, slow down the impact of the water flow on the bridge pier, and extend the service life of the bridge.

Description

[0001] The invention relates to a bridge pier drag reduction device, in particular to a bridge pier drag reduction device based on a Venturi bubble generator. Background Art

[0002] Entering the 21st century, with the continuous development of human civilization and the continuous advancement of science and technology, in order to meet people's huge demand for travel and transportation, more and more cross-river bridges and cross-river bridges have been built one after another. However, the erosion of the bridge body, especially the piers, by water flow is quite serious. Ordinary bridges generally do not protect the piers and do not have any protective devices. Therefore, the impact and erosion of the water flow on the piers have brought great harm to the safety and service life of the bridge body. Summary of the invention

[0003] In order to solve the above-mentioned problems, the purpose of the present invention is to provide a new pier drag reduction device based on a Venturi bubble generator. The device generates a mixed layer of microbubbles and water on the surface of the pier through the Venturi bubble generator, thereby minimizing the erosion of the pier by the water flow, reducing the flow resistance of the water, and extending the life of the bridge body as much as possible. At the same time, the device does not require other external energy sources such as electricity, and can work only by using the kinetic energy of water, which is efficient and environmentally friendly.

[0004] In order to achieve the above object, the technical solution adopted by the present invention is:

[0005] A pier drag reduction device based on a Venturi bubble generator comprises a Venturi bubble generator group 1, a bracket 2 and a Venturi bubble generator 3, wherein the bottom of the bracket 2 is implanted in the riverbed at the bottom of the river, so that the bracket 2 can stably support the Venturi bubble generator group 1, the Venturi bubble generator group 1 is supported by the bracket 2 and placed in water, and the Venturi bubble generator group 1 is evenly arranged downstream in the direction of the incoming water flow, i.e., upstream of the water where the bridge pier is positioned.

[0006] After optimization calculation, the optimal size of the Venturi bubble generator 3 is obtained as follows: the Venturi bubble generator 3 is 40 cm long, the inlet outer diameter is 11 cm, the inlet inner diameter is 10 cm, the outlet outer diameter is 12 cm, the outlet inner diameter is 11 cm, the throat outer diameter is 12 cm, the throat inner diameter is 5 cm, the air inlet outer diameter is 2.5 cm, and the air inlet inner diameter is 2 cm, among which the throat length is 6 cm, the length of the tapering section is 4 cm, the length of the expanding section is 5 cm, the length of the inlet section is 12 cm, the stable section length of the expanding section is 13 cm, and the stable section length of the tapering section is 12 cm; the height of the air inlet pipe 4 connected to each Venturi bubble generator 3 is 50 cm higher than the horizontal water level.

[0007] The Venturi bubble generators 3 in each group of Venturi bubble generator groups 1 are placed in parallel in the horizontal direction, and the distance between two adjacent Venturi bubble generators 3 is 20 cm. Each group of Venturi bubble generator groups 1 is placed vertically along the pier support direction, that is, placed along the horizontal plane direction, and the two adjacent groups of Venturi bubble generator groups 1 are parallel and the vertical distance is 30 cm.

[0008] The number of Venturi bubble generators 3 in each Venturi bubble generator group 1 is related to the hydraulic radius of the pier. When the hydraulic radius of the pier is less than or equal to 8 cm, only one Venturi bubble generator 3 is needed in each Venturi bubble generator group 1. The integer value obtained by dividing the value of the hydraulic radius of the pier by 8 is the number of Venturi bubble generators 3 in each Venturi bubble generator group 1.

[0009] In the horizontal direction, the outlet of the Venturi bubble generator 3 is 10 cm away from the bridge pier. The 30 cm away from the bottom of the bridge pier is taken as the baseline. Starting from this baseline, a Venturi bubble generator group 1 is arranged every 30 cm rising in the vertical direction. This is continued until the distance from the flat water level is less than 30 cm, at which time no more Venturi bubble generator group 1 is arranged.

[0010] The structure of each venturi bubble generator 3 in the venturi bubble generator group 1 is exactly the same, and all venturi bubble generators 3 are arranged in parallel relative to each other. The air introduction pipe (4) of the venturi bubble generator 3 is not necessarily strictly required to be a straight pipe. The shape of the air introduction pipe can also be adjusted according to the river hydrological conditions. For example, the air introduction pipe can be arranged along the bridge pier to reduce the impact of water flow on the air introduction pipe (4). As long as the air inlet of the air introduction pipe (4) is 50 cm higher than the horizontal water level to prevent water flow from entering the air inlet of the air introduction pipe (4), it can be done. For clarity, Figure 1 and Figure 2 The air inlet pipes (4) of the venturi bubble generator group 1 shown are all straight pipes, which is a special case.

[0011] The Venturi bubble generator group 1 uses the kinetic energy provided by the water flow to bring air into the Venturi bubble generator 3, generate bubbles at the outlet, and form a mixed layer of microbubbles and water on the surface of the pier to achieve the purpose of protecting the pier and extending the life of the bridge body.

[0012] The present invention has the following advantages:

[0013] The present invention provides a bridge pier drag reduction device based on a venturi bubble generator, which covers the impact surface of the bridge pier with bubbles generated by the venturi bubble generator, thereby reducing the force on the bridge pier, extending the life of the bridge pier, and greatly increasing the safety of the bridge. At the same time, since there is currently a lack of mature technology for the protection of bridge piers, this device has great application value. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] Figure 1 This is a schematic diagram of the overall structure of a bridge pier drag reduction device based on a venturi bubble generator according to the present invention, wherein each venturi bubble generator group 1 has three venturi bubble generators 3 and there are three venturi bubble generator groups 1

[0015] Figure 2 A top view of the relative positions of a bridge pier drag reduction device based on a venturi bubble generator when each venturi bubble generator group 1 has three venturi bubble generators 3 according to the present invention.

[0016] Figure 3 A cross-sectional view of a Venturi bubble generator 3 in a pier drag reduction device based on a Venturi bubble generator according to the present invention

[0017] Figure 4 This is a structural diagram of the air introduction pipe (4) of the Venturi bubble generator 3 in the bridge pier drag reduction device based on the Venturi bubble generator of the present invention.

[0018] Figure 5 This is a structural diagram of the connection between the Venturi bubble generator 3 and the gradually expanding stable section and the gradually contracting stable section in a bridge pier drag reduction device based on the Venturi bubble generator of the present invention. DETAILED DESCRIPTION

[0019] The present invention is further described in detail below in conjunction with the accompanying drawings and specific embodiments.

[0020] like Figure 1 As shown, the venturi bubble generator group 1, the bracket 2, the venturi bubble generator 3 and the air introduction pipe 4 connected to the venturi bubble generator 3 constitute a bridge pier drag reduction device based on the venturi bubble generator. The bottom of the bracket 2 is implanted in the riverbed at the bottom of the river, so that the bracket 2 can stably support the venturi bubble generator group 1. The venturi bubble generator group 1 is supported by the bracket 2 and placed in the water. The venturi bubble generator group 1 is evenly arranged downstream in the direction of the water flow.

[0021] After optimization calculation, the optimal size of the Venturi bubble generator 3 is obtained as follows:

[0022] The venturi bubble generator 3 is 40 cm long, with an outer diameter of 11 cm at the inlet, an inner diameter of 10 cm at the inlet, an outer diameter of 12 cm at the outlet, an inner diameter of 11 cm at the outlet, an outer diameter of 12 cm at the throat, an inner diameter of 5 cm at the throat, an outer diameter of 2.5 cm at the air inlet, and an inner diameter of 2 cm at the air inlet, wherein the throat length is 6 cm, the length of the tapering section is 4 cm, the length of the expanding section is 5 cm, the length of the inlet section is 12 cm, the stable section length of the expanding section is 13 cm, and the stable section length of the tapering section is 12 cm; the height of the air inlet pipe 4 connected to each venturi bubble generator 3 is 50 cm higher than the horizontal water level.

[0023] The structure of each venturi bubble generator 3 in the venturi bubble generator group 1 is exactly the same, and all the venturi bubble generators 3 are arranged in parallel relative to each other. The air introduction pipe 4 of the venturi bubble generator 3 is not necessarily strictly required to be a straight pipe, and the shape of the air introduction pipe can also be adjusted according to the river hydrological conditions, as long as the air inlet of the air introduction pipe 4 is 50 cm higher than the horizontal water level. In order to make the diagram clearer and more concise, Figure 1 and Figure 2 The air inlet pipes 4 of the venturi bubble generator group 1 shown are all straight pipes, which is a special case.

[0024] Since the arrangement of the Venturi bubble generator 3 on the bridge pier will bring additional force to the bridge pier, which will increase the burden on the bridge pier to a certain extent and will have an adverse effect on the bridge pier, the design is to support the Venturi bubble generator 3 with a bracket, and the bottom of the bracket 2 is embedded in the river bed, so that the bracket 2 can stably support the Venturi bubble generator 3.

[0025] The Venturi bubble generators 3 in each group of Venturi bubble generator groups 1 are placed in parallel in the horizontal direction, and the distance between two adjacent Venturi bubble generators 3 is 20 cm. Each group of Venturi bubble generator groups 1 is placed vertically along the pier support direction (i.e. placed in the horizontal direction), and the two adjacent groups of Venturi bubble generator groups 1 are parallel and the vertical distance is 30 cm.

[0026] The number of Venturi bubble generators 3 in each Venturi bubble generator group 1 is related to the hydraulic radius of the pier. When the hydraulic radius of the pier is less than or equal to 8 cm, only one Venturi bubble generator 3 is needed in each Venturi bubble generator group 1. The integer value obtained by dividing the value of the hydraulic radius of the pier by 8 is the number of Venturi bubble generators 3 in each Venturi bubble generator group 1.

[0027] The outlet of the Venturi bubble generator 3 is 10 cm away from the bridge pier. The riverbed 30 cm away from the bottom of the pier is taken as the baseline. Starting from this baseline, a Venturi bubble generator group 1 is arranged every 30 cm rising until no Venturi bubble generator group 1 is arranged less than 30 cm away from the flat water level. The number of Venturi bubble generator groups 1 can be dynamically adjusted according to the water depth.

[0028] Since the normal water level is the lowest water level of the river in a year, which generally occurs during the dry season, arranging the Venturi bubble generator group 1 below the normal water level ensures that all Venturi bubble generators 3 work simultaneously, thus avoiding equipment idleness and saving costs.

[0029] like Figure 3As shown, a Venturi bubble generator 3 with parallel air intake is used to generate bubbles. Since the outlet of the Venturi bubble generator 3 is only 10 cm away from the bridge pier, it is enough for all the bubbles to reach the surface of the bridge pier after leaving the Venturi bubble generator 3. As the bubbles accumulate, a mixed layer of microbubbles and water is formed on the surface of the bridge pier.

[0030] When water flows against the bridge pier, the kinetic energy is provided by the flow of water, and no external energy is required. After the water flows through the Venturi bubble generator group 1, a large number of fine bubbles are generated and attached to the surface of the bridge pier, forming a mixed layer of microbubbles and water, so as to achieve the effect of reducing the resistance of the bridge pier, reducing the corrosion of the bridge pier, and extending the life of the bridge body.

[0031] The above is a complete working cycle of the Venturi bubble generating device for reducing the drag of bridge piers in water according to the present invention.

[0032] Specific embodiment: For example, a cylindrical pier with a diameter of 96 cm is located in a river with a water depth of 270 cm. It is calculated that the hydraulic radius of the pier is 96*0.25=24 cm, 24÷8=3, and because 270÷30=9 groups, it can be seen from the above specific implementation method that each group of Venturi bubble generator groups 1 has 3 Venturi bubble generators 3, and a total of 9 groups of Venturi bubble generator groups 1 need to be arranged from top to bottom, and the top group of Venturi bubble generator groups 1 is exactly in the same plane as the flat water level.

[0033] For another example, a cylindrical bridge pier with a diameter of 92 cm is located in a river with a water depth of 215 cm. It is calculated that the hydraulic radius of the pier is 92*0.25=23 cm, 23÷8=2 with a remainder of 7 cm, 7cm<8cm, rounded to 2, and because 215÷30=7 groups with a remainder of 5 cm, 5cm<30cm, it can be seen from the above specific implementation method that each group of Venturi bubble generator groups 1 has 2 Venturi bubble generators 3, and a total of 7 groups of Venturi bubble generator groups 1 need to be arranged from top to bottom. At this time, the top group of Venturi bubble generator groups 1 is 5 cm below the horizontal water level.

[0034] For another example, a cylindrical bridge pier with a diameter of 92 cm is located in a river with a water depth of 239 cm. It is calculated that the hydraulic radius of the pier is 92*0.25=23 cm, 23÷8=2 times a remainder of 7 cm, 7cm<8cm, rounded to 2, and because 239÷30=7 groups of a remainder of 29 cm, 29cm<30cm, it can be seen from the above specific implementation method that each group of Venturi bubble generator groups 1 has 2 Venturi bubble generators 3, and a total of 7 groups of Venturi bubble generator groups 1 need to be arranged from top to bottom. At this time, the topmost group of Venturi bubble generator groups 1 is also 29 cm below the horizontal water level.

[0035] This pier drag reduction device based on the Venturi bubble generator can effectively reduce the corrosion of the pier caused by the impact of water flow on the pier. At the same time, since the device does not require additional energy input, it is also of great significance for energy conservation and emission reduction. In addition, there are currently few methods and equipment for pier protection. Therefore, this device has a very broad development and application prospect in the field of pier protection.

Claims

1. A bridge pier drag reduction device based on a Venturi bubble generator, comprising a Venturi bubble generator group (1), a bracket (2), a Venturi bubble generator (3) and an air introduction pipe (4) connected to the Venturi bubble generator (3), characterized in that: The bottom of the bracket (2) is implanted in the riverbed at the bottom of the river. The bracket (2) stably supports the venturi bubble generator group (1). The venturi bubble generator group (1) is supported by the bracket (2) and placed in water. The venturi bubble generator group (1) is evenly arranged downstream in the direction of the water flow upstream of the bridge pier. The venturi bubble generators (3) in each group of venturi bubble generator groups (1) are arranged in parallel in the horizontal direction. The distance between two adjacent venturi bubble generators (3) is 20 cm. Each group of venturi bubble generator groups (1) is arranged vertically along the supporting direction of the bridge pier. Two adjacent groups of venturi bubble generator groups (1) are parallel and the distance between them is 30 cm. The outlet of the venturi bubble generator (3) is 10 cm away from the bridge pier in the horizontal direction. The riverbed 30 cm away from the bottom of the bridge pier is used as a reference line. Starting from this reference line, one venturi bubble generator group (1) is arranged every 30 cm rise in the vertical direction of the water surface. The arrangement is continued until the distance from the normal water level is less than 30 cm. No more arrangement is made.

2. The pier drag reduction device based on the Venturi bubble generator according to claim 1, characterized in that: The venturi bubble generator (3) is 40 cm long, with an inlet outer diameter of 11 cm, an inlet inner diameter of 10 cm, an outlet outer diameter of 12 cm, an outlet inner diameter of 11 cm, a throat outer diameter of 12 cm, a throat inner diameter of 5 cm, an air inlet outer diameter of 2.5 cm, and an air inlet inner diameter of 2 cm; wherein the throat length is 6 cm, the length of the gradually contracting section is 4 cm, the length of the gradually expanding section is 5 cm, the length of the inlet section is 12 cm, the length of the stable section of the gradually expanding section is 13 cm, and the length of the stable section of the gradually contracting section is 12 cm; each venturi bubble generator (3) is respectively connected to an air introduction pipe (4), and the height of all air introduction pipes (4) is 50 cm higher than the horizontal water level.

3. The pier drag reduction device based on the Venturi bubble generator according to claim 1, characterized in that: The number of Venturi bubble generators (3) in each Venturi bubble generator group (1) is related to the hydraulic radius of the bridge pier. When the hydraulic radius of the bridge pier is less than or equal to 8 cm, only one Venturi bubble generator (3) is required in each Venturi bubble generator group (1). The integer value obtained by dividing the value of the hydraulic radius of the bridge pier by 8 is the number of Venturi bubble generators (3) in each Venturi bubble generator group (1).

4. The pier drag reduction device based on the Venturi bubble generator according to claim 1, characterized in that: The structure of each venturi bubble generator (3) in the venturi bubble generator group (1) is completely the same, and all the venturi bubble generators (3) are arranged in parallel relative to each other. The air introduction pipe (4) of the venturi bubble generator (3) is not necessarily strictly required to be a straight pipe. The air introduction pipe (4) is arranged along the bridge pier to reduce the impact of water flow on the air introduction pipe (4). However, it is necessary to ensure that the air inlet of the air introduction pipe (4) is 50 cm above the horizontal water level to prevent water flow from entering the air inlet of the air introduction pipe (4).

5. The pier drag reduction device based on the Venturi bubble generator according to claim 1, characterized in that: The venturi bubble generator group (1) uses the kinetic energy provided by the water flow to work, bringing air into the venturi bubble generator (3) through the air introduction pipe (4), generating bubbles at its outlet, and forming a mixed layer of microbubbles and water on the surface of the bridge pier.

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