CN209992140U - A model sand selection device for physical model test of hyperpycnal flow - Google Patents

Abstract

The utility model provides a model sand selection device for a hyperpycnal flow physical model test, which relates to the technical field of a hyperpycnal flow physical model test based on a basic water tank test, and solves the problem that the prior art is not used for selecting sand with specific characteristics. Technical problems with the installation of the model sand. The model sand selection device used for the physical model test of hyperpycnal flow includes a muddy water storage tank, a muddy water conveying device, a muddy water outflow flow control device, a detection device and a river bed simulation device. The muddy water outflow flow control device is communicated with the muddy water outflow flow control device and the river bed simulation device. And the turbidity value characteristics screen out the required model sand for the low sand content hyperpycnal flow physical model test, which fills the gap of the device for selecting model sand with specific characteristics.

Description

A model sand selection device for physical model test of hyperpycnal flow

technical field

The utility model relates to the technical field of the hyperpycnal flow physical model test based on the basic water tank test, in particular to a model sand selection device used for the hyperpycnal flow physical model test.

Background technique

Hyperpycnal flow refers to the stratified flow due to the difference in fluid density in the gravitational field, also known as density flow or gravity flow. The temperature of each part of the water flow is different, and the water flow carries fine-grained sediment or contains salt, etc., which will produce a difference in fluid density and form a hyperpycnal flow. Density flow can be divided into two types: two-layer system and multi-layer system. In nature, the manifestations of hyperpycnal flow include stratified undercurrent in reservoirs, saltwater intrusion into freshwater at river estuaries, and fronts formed by cold and warm air currents in the atmosphere. For water flow, the main factors that cause density difference are: sand content, water temperature and dissolved matter content. The hyperpycnal flow formed by the sediment carried by the water flow is called muddy water hyperpycnal flow. The turbid river water flowing into the reservoir dives into the bottom of the reservoir in a tongue-like flow, and moves forward along the bottom of the reservoir under the clear water of the reservoir, forming a reservoir pycnometric flow; when the two rivers meet, when the sediment content of each flow is different, it can be generated at the confluence. The phenomenon of layered movement, forming a river channel hyperpycnal flow. The density flow caused by the different temperature of the water flow is called the temperature differential density flow. The cold river water entering the lake (or reservoir) dives into the bottom of the lake to form the lower layer of density flow and moves forward; after the cooling water of the thermal power plant is heated by the condenser and discharged into the river, it flows along the upper layer of the cooler river water, forming the upper layer of density flow. . Due to the fact that the water flow contains salt, the density flow is called brine density flow. The rational use of the muddy water density flow at the bottom of the reservoir can remove the sediment and reduce the sedimentation of the reservoir. It is the main measure for the reduction of sedimentation in the reservoir. In the project, the sedimentation tank is designed according to the characteristics of gravity flow, which is conducive to sedimentation and better water quality; the construction of thermal power plants can take advantage of the gravity flow characteristics of temperature difference, set deeper water intake holes to draw cold water, and set higher water intake holes. Drainage holes discharge hot water, so studying and utilizing the properties of gravity flow can facilitate people's lives. When studying hyperpycnal flow, people generally use model sand to conduct tests in a simulated test device, but there is no device for screening model sand with specific characteristics in the prior art, so as to use the screened model sand to conduct tests containing specific sand. The hyperpycnal flow physical model test.

Utility model content

The purpose of the present utility model is to provide a model sand selection device used for the physical model test of hyperpycnal flow, so as to solve the technical problem that there is no device for selecting model sand with specific characteristics in the prior art.

To achieve the above object, the utility model provides the following technical solutions:

The utility model provides a model sand selection device for a physical model test of hyperpycnal flow, comprising a muddy water storage tank containing model sand, a muddy water conveying device, a muddy water outflow flow control device, a detection device and a river bed simulation device. The muddy water storage tank is communicated with the muddy water outflow flow control device through the muddy water conveying device, and the muddy water outflow control device is communicated with the riverbed simulation device, wherein the riverbed simulation device is filled with Clear water, different types of model sands simulate surface, middle and bottom muddy water hyperpycnal flow by adjusting the temperature difference between clear water and muddy water. By controlling the change of muddy water sediment content and the change of muddy water flow rate, the detection device can be used to measure and record the data of the flow velocity, thickness and turbidity value of multiple groups of muddy water density flow at different times, and through the comparison of the data Select the desired model sand.

Optionally, the muddy water outflow flow control device is a box body, the side wall of the box body is provided with a flow hole, and the width of the flow hole on different horizontal planes is different.

Optionally, the flow holes are circular.

Optionally, the river bed simulation device includes a water tank, a fore pond and a bottom slope, the fore pond and the bottom slope are arranged in the water tank, the fore pond and the bottom slope are connected, and the water tank support With metal structure, the side walls are made of transparent material.

Optionally, the height of the fore pool in the water tank is higher than the height of the bottom slope, the connecting part of the fore pool and the bottom slope is a slope, and the height of the bottom slope is determined by the fore pool. to the end of the sink tapering off.

Optionally, the muddy water conveying device is a water pump conveying device.

Optionally, a stirring device is provided in the muddy water storage tank.

Optionally, the detection device includes a camera, and the camera is movably arranged near the water tank.

Optionally, the detection device includes an electromagnetic flow meter, and the electromagnetic flow meter is disposed at the starting end of the bottom slope.

Optionally, the detection device further includes an OBS3+ turbidity meter to measure the turbidity of the density flow.

The utility model provides a model sand selection device for a physical model test of hyperpycnal flow, comprising a muddy water storage tank containing model sand, a muddy water conveying device, a muddy water outflow flow control device, a detection device and a river bed simulation device. The muddy water storage tank is communicated with the muddy water outflow flow control device through the muddy water conveying device, and the muddy water outflow control device is communicated with the riverbed simulation device, wherein the riverbed simulation device is filled with Clear water, the utility model can simulate the formation and evolution process of the hyperpycnal flow in the river channel in the river bed simulation device, and enables the operator to calculate the flow velocity, thickness and turbidity value of the hyperpycnal flow formed by different model sands under different conditions. The required model sand is screened out to carry out the physical model test of the low sand content hyperpycnal flow. The utility model is simple in structure and convenient to use, and fills the gap of the device for selecting model sand with specific characteristics.

Description of drawings

In order to more clearly illustrate the embodiments of the present utility model or the technical solutions in the prior art, the following briefly introduces the accompanying drawings that need to be used in the description of the embodiments or the prior art. Obviously, the accompanying drawings in the following description These are just some embodiments of the present invention, and for those of ordinary skill in the art, other drawings can also be obtained from these drawings without creative effort.

Fig. 1 is a kind of overall structure schematic diagram of the model sand selection device used for the physical model test of hyperpycnal flow of the present invention;

Figure 2 is the right side view of the muddy water outflow flow control device of the model sand selection device used for the physical model test of hyperpycnal flow.

In the figure, 1, muddy water storage tank; 2, muddy water conveying device; 3, muddy water flow control device; 4, river bed simulation device; 5, flow hole; 6, water tank; 7, fore pond; 8, bottom slope.

Detailed ways

In order to make the objectives, technical solutions and advantages of the present invention more clear, the technical solutions of the present invention will be described in detail below. Obviously, the described embodiments are only a part of the embodiments of the present invention, but not all of the embodiments. Based on the embodiments of the present invention, all other implementations obtained by those of ordinary skill in the art without creative work fall within the scope of protection of the present invention.

The utility model provides a model sand selection device used for a physical model test of hyperpycnal flow, as shown in FIG. , detection device and riverbed simulation device 4, described muddy water storage tank 1 is communicated with described muddy water outflow flow control device 3 through described muddy water conveying device 2, and described muddy water outflow flow control device 3 is connected with described riverbed The simulation device 4 is connected, wherein the river bed simulation device 4 is filled with clear water, and different kinds of model sands simulate the surface, middle and bottom muddy water density flow respectively by adjusting the temperature difference between the clear water and the muddy water. When the sand forms the surface, middle and bottom muddy water density flow respectively, people can use the detection device to measure the changes of multiple groups of muddy water density flow at different times by controlling the change of muddy water sediment content and the change of muddy water flow rate. The data of flow rate, thickness and turbidity value are recorded, and the required model sand is selected by comparing the data.

The utility model can simulate the formation and evolution process of the hyperpycnal flow in the river channel in the river bed simulation device 4, and enables the operator to use the flow velocity, thickness and turbidity value characteristics of the hyperpycnal flow formed by different model sands under different conditions. The required model sand is screened out to carry out the physical model test of the low sand content hyperpycnal flow. The utility model is simple in structure and convenient to use, and fills the gap of the device for selecting model sand with specific characteristics;

Further, a muddy water storage tank 1 is provided in front of the muddy water outflow control device 3, and the muddy water storage tank 1 is communicated with the muddy water outflow control device 3 through the muddy water conveying device 2, and the muddy water is communicated with the muddy water outflow control device 3. The water is transported to the muddy water outflow control device 3, so that the fluctuation of the muddy water in the muddy water outflow control device 3 can be reduced as much as possible, so that the muddy water can stably flow out from the muddy water outflow control device 3, so as to ensure the test results. stability.

As an optional embodiment, as shown in FIG. 2 , the muddy water outflow flow control device 3 is a box body, and the side wall of the box body is provided with a flow hole 5 , and the flow hole 5 has different widths on different horizontal planes. .

The muddy water outflow flow control device 3 of the present invention is a box, which is used to temporarily store muddy water. The side wall of the box is provided with a flow hole 5, and the muddy water can flow from the flow hole 5 to the river bed simulation device 4 for simulation. Different gravity flow, the width of the flow hole 5 on different horizontal planes is different, the flow rate of the muddy water flowing out of the flow hole 5 can be controlled according to the water level of the muddy water in the box, so that the user can control a variable of the test, And the structure is simple and practical.

As an optional embodiment, the flow holes 5 are circular.

The flow hole 5 of the present utility model is arranged in a circular shape, so that the outflow flow gap of muddy water is large, and the outflow flow is easy to calculate; the diameter of the flow hole 5 is preferably 2.5cm.

As an optional embodiment, the river bed simulation device 4 includes a water tank 6, a fore tank 7 and a bottom slope 8, the fore tank 7 and the bottom slope 8 are arranged in the water tank 6, and the fore tank 7 and the bottom slope 8 are arranged in the water tank 6. The bottom slopes 8 are connected, the support of the water tank 6 is made of metal structure, and the side wall is made of transparent material.

The river bed simulation device 4 of the present invention includes a water tank 6, a fore tank 7 and a bottom slope 8, the fore tank 7 and the bottom slope 8 are arranged in the water tank 6, the fore tank 7 and the bottom slope 8 8 phases are connected, the water tank 6 simulates the river channel, the bottom slope 8 simulates the upstream and downstream of the river bottom, and the fore pond 7 is used to eliminate the potential energy of muddy water falling from the muddy water flow control device 3, and the muddy water flows from the fore pond 7 to the bottom slope 8 Form a weighted flow; the support of the water tank 6 adopts a metal structure, which fully guarantees the strength of the water tank 6, and the side wall is made of transparent material, which is convenient for observation in the test; further, the total length of the water tank 6 is 30m, 0.1m wide and 0.8m high m.

As an optional embodiment, the height of the front pool 7 in the water tank 6 is higher than the height of the bottom slope 8, the connecting part of the front pool 7 and the bottom slope 8 is a slope, and the The height of the bottom slope 8 gradually decreases from the front pool 7 to the end of the water tank 6 .

In the present invention, the height of the front pool 7 in the water tank 6 is higher than the height of the bottom slope 8, so that the mixed water flows from the front pool 7 to the bottom slope 8; The connecting part is an inclined plane, which ensures that the muddy water evenly transitions to the bottom slope 8, makes the muddy water stable, and ensures the reliability of the experiment; Simulate the upstream and downstream of the river to make the test closer to the real situation and ensure the reliability of the test results.

As an optional embodiment, the muddy water conveying device 2 is a water pump conveying device.

The muddy water conveying device 2 of the utility model is a water pump conveying device, which has strong versatility and is convenient to use.

As an optional embodiment, a stirring device is provided in the muddy water storage tank 1 .

The muddy water storage tank 1 of the utility model is provided with a stirring device to prevent the precipitation of muddy water and ensure the smooth progress of the test.

As an optional embodiment, the detection device includes a camera, and the camera is movably arranged near the water tank 6 .

The detection device of the present invention includes a camera, which is movably arranged near the water tank 6, and the camera is used to track the movement of the head of the mass flow to record the time taken for the mass flow to reach each section.

As an optional embodiment, the detection device includes an electromagnetic flow meter, and the electromagnetic flow meter is disposed at the starting end of the bottom slope 8 .

The electromagnetic flow meter of the present invention is arranged at the starting end of the bottom slope 8 to measure the flow velocity.

As an optional embodiment, the detection device further includes an OBS3+ turbidity meter to measure the density flow turbidity.

The detection device of the utility model further comprises an OBS3+ turbidity meter, and the OBS3+ turbidity meter is used to record the turbidity value of the head of the density flow and the vertical line turbidity value of each section. After the test, the designated tester obtains the sand content through the relationship between the turbidity and the sand content that was calibrated in the previous stage.

The above are only specific embodiments of the present invention, but the protection scope of the present invention is not limited to this. Replacement should be covered within the protection scope of the present invention. Therefore, the protection scope of the present invention should be based on the protection scope of the claims.

Claims (10)

1. a model sand selection device for hyperpycnal flow physical model test, is characterized in that: comprise the muddy water storage tank (1) containing model sand, muddy water conveying device (2), muddy water outflow flow control device ( 3), a detection device and a riverbed simulation device (4), the muddy water storage tank (1) communicates with the muddy water outflow flow control device (3) through the muddy water conveying device (2), and the muddy water The water outflow flow control device (3) is communicated with the riverbed simulation device (4), wherein the riverbed simulation device (4) is filled with clear water, and different kinds of model sands are respectively adjusted by adjusting the temperature difference between the clear water and the muddy water. To simulate the surface, middle and bottom muddy water hyperpycnal flow, when each model sand forms the surface, middle and bottom muddy water hyperpycnal flow, people can control the changes of muddy water sediment content and muddy water flow. The detection device is used to measure and record the data of the flow velocity, thickness and turbidity value of multiple groups of muddy water density flow at different times, and the required model sand is selected through the comparison of the data. 2. according to the model sand selection device that is used for the physical model test of hyperpycnal flow according to claim 1, it is characterized in that: described muddy water outflow flow control device (3) is box body, and described box body side wall is provided with Flow holes (5), the flow holes (5) have different widths on different horizontal planes. 3 . The model sand selection device for the physical model test of hyperpycnal flow according to claim 2 , wherein the flow hole ( 5 ) is circular. 4 . 4. The model sand selection device for hyperpycnal flow physical model test according to claim 1, characterized in that: the riverbed simulation device (4) comprises a water tank (6), a fore pond (7) and a bottom slope ( 8), the front pool (7) and the bottom slope (8) are arranged in the water tank (6), the front pool (7) and the bottom slope (8) are connected, and the water tank ( 6) The bracket adopts metal structure, and the side wall is made of transparent material. 5. The model sand selection device for the physical model test of hyperpycnal flow according to claim 4, characterized in that: the height of the fore pond (7) in the water tank (6) is higher than the bottom slope (8), the connecting part of the front pool (7) and the bottom slope (8) is an inclined plane, and the height of the bottom slope (8) is from the front pool (7) to the water tank (6) ) becomes smaller at the end. 6 . The model sand selection device for the physical model test of hyperpycnal flow according to claim 1 , wherein the muddy water conveying device ( 2 ) is a water pump conveying device. 7 . 7 . The model sand selection device for the physical model test of hyperpycnal flow according to claim 1 , wherein a stirring device is provided in the muddy water storage tank ( 1 ). 8 . 8 . The model sand selection device for hyperpycnal flow physical model test according to claim 4 , wherein the detection device comprises a camera, and the camera is movably arranged near the water tank ( 6 ). 9 . 9. The model sand selection device for a hyperpycnal flow physical model test according to claim 8, wherein the detection device comprises an electromagnetic flow meter, and the electromagnetic flow meter is arranged on the bottom slope (8) starting end. 10 . The model sand selection device for the physical model test of the density flow according to claim 9 , wherein the detection device further comprises an OBS3+ turbidimeter to measure the turbidity of the density flow. 11 .

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