Flow stabilizing device for hydraulic model test

Abstract

The utility model belongs to the field of hydraulic model tests, and discloses a hydraulic model test flow stabilizing device which comprises a measuring weir, the inlet end of the measuring weir is connected with a measuring weir forebay, the outlet end of the measuring weir is connected with a terrain forebay, and the other end of the measuring weir forebay is internally connected with a water supply pipeline. And water in the terrain forebay enters the test terrain through the steady flow lattice wall. According to the utility model, the phenomenon of unstable inflow caused by unstable incoming flow in a hydraulic model test with a small required flow is improved.

Description

Technical Field

[0001] The utility model belongs to the field of hydraulic model tests, and particularly relates to a steady flow device for hydraulic model tests. Background Technique

[0002] Hydraulic model tests are based on the principle of hydraulic similarity to observe the flow movement law in the hydraulic building model and provide a scientific basis for engineering design and operation. In practical applications, there are unstable incoming flow phenomena caused by factors such as unstable site water pressure and aging of the water supply system. For hydraulic model tests with a relatively large required flow rate, the influence of this flow rate change range is relatively small, but for model tests with a relatively small required flow rate, this flow rate change will greatly reduce the reliability of the experimental results. Content of the Utility Model

[0003] The purpose of the utility model is to provide a steady flow device for hydraulic model tests, which improves the phenomenon of large and small incoming flow caused by unstable incoming flow in hydraulic model tests with a relatively small required flow rate.

[0004] To achieve the above purpose, the technical solution adopted by the utility model is as follows:

[0005] A steady flow device for hydraulic model tests includes a weir. The inlet end of the weir is connected to the forebay of the weir, the outlet end of the weir is connected to the forebay of the terrain, the other end of the forebay of the weir is internally connected to a water supply pipeline, and the water in the forebay of the terrain enters the test terrain through a steady flow porous wall.

[0006] Preferably, an overflow weir is arranged on the side wall of the forebay of the weir. Overflow weir grooves are left at the four corners of the side wall of the forebay of the weir. Both sides of the overflow weir are embedded in the overflow weir grooves. Drainage channels are arranged around the forebay of the weir, and drain outlets are arranged at the bottom of the drainage channels.

[0007] Preferably, the overflow weir is a segmented prefabricated overflow weir, each section is 1 cm high, and the top elevation of the overflow weir is basically flat but slightly lower than the elevation of the required head over the weir of the weir.

[0008] Preferably, a number of steady flow partitions are arranged at the water inlet end of the weir. The length and width of the steady flow partitions are the same as those of the weir, and a plurality of water passing holes are arranged on the steady flow partitions.

[0009] Preferably, a weir plate is arranged at the water outlet end of the weir, and the weir plate of the weir is a right triangle weir.

[0010] The beneficial effect of the utility model is: it improves the phenomenon of large and small incoming flow caused by unstable incoming flow in hydraulic model tests with a relatively small required flow rate. Description of the Drawings

[0011] Figure 1It is the plan view of the steady flow device for the hydraulic model test of the utility model.

[0012] Figure 2 It is the side view of the steady flow device for the hydraulic model test of the utility model.

[0013] Figure 3 It is Figure 1 the structure diagram of the steady flow partition in

[0014] Figure 4 It is Figure 1 the structure diagram of the weir plate in

[0015] In the figure, 1 is the water supply pipeline; 11 is the valve; 2 is the forebay of the water measuring weir; 3 is the water measuring weir; 4 is the forebay of the terrain; 5 is the steady flow flower wall; 6 is the test terrain; 7 is the overflow weir; 8 is the steady flow partition; 81 is the water passing hole; 9 is the drainage channel; 91 is the drain outlet; 10 is the weir plate of the water measuring weir. Specific implementation mode

[0016] To make the purpose, technical solution and advantages of the utility model clearer, the following combines the drawings and embodiments of the utility model to clearly and completely describe the technical solution of the utility model.

[0017] As Figures 1-4 shown, a steady flow device for a hydraulic model test includes a water supply pipeline 1, a forebay 2 of the water measuring weir, a water measuring weir 3, a forebay 4 of the terrain, a steady flow flower wall 5, and a test terrain 6.

[0018] The inlet end of the water measuring weir 3 is connected to the forebay 2 of the water measuring weir, the outlet end of the water measuring weir 3 is connected to the forebay 4 of the terrain, the other end of the forebay 2 of the water measuring weir is internally connected to the water supply pipeline 1, and the water in the forebay 4 of the terrain enters the test terrain 6 through the steady flow flower wall 5.

[0019] The outlet of the water supply pipeline 1 is arranged at the bottom of the forebay 2 of the water measuring weir, and a valve 11 is arranged on the water supply pipeline 1.

[0020] An overflow weir 7 is arranged on the side wall of the forebay 2 of the water measuring weir, overflow weir grooves 21 are left at the four corners of the side wall of the forebay 2 of the water measuring weir, and both sides of the overflow weir 7 are embedded in the overflow weir grooves 21. Drainage channels 9 are arranged around the forebay 2 of the water measuring weir, and drain outlets 91 are arranged at the bottom of the drainage channels 9.

[0021] The overflow weir 7 is a segmented assembled overflow weir, each section is 1 cm high, and the assembly height is selected according to the required head above the weir, so that the top elevation of the overflow weir 7 is basically flat but slightly lower than the elevation of the required head above the weir of the water measuring weir 3.

[0022] Four steady flow partitions 8 are arranged at the inlet end of the water measuring weir 3. The length and width of the steady flow partition 8 are the same as those of the water measuring weir 3, and a plurality of water passing holes 81 are arranged on the steady flow partition 8.

[0023] A weir plate 10 is provided at the water outlet end of the water measuring weir 3. The weir plate 10 of the water measuring weir is a right-angled triangular weir, with a weir width L, a weir height H, and a head over the weir h.

[0024] A measuring cylinder (not shown in the figure) and a water level measuring needle (not shown in the figure) are provided on the side wall of the water measuring weir 3.

[0025] For a hydraulic model test with a relatively small required flow rate, it is more sensitive to flow rate changes. The flow from the water supply pipeline 1 all enters the forebay 2 of the water measuring weir and then enters the water measuring weir 3. When the flow rate changes, the flow rate flowing into the test terrain 6 also changes accordingly. The flow from the water supply pipeline 1 all enters the water measuring weir 3, so that the water flow in the water measuring weir 3 bears all the flow fluctuations. The steady flow device for the hydraulic model test provided by the present utility model is provided with an overflow weir 7 in a nearly complete circle in the forebay 2 of the water measuring weir. The top elevation of the overflow weir 7 is basically flat but slightly lower than the water level corresponding to the required head over the weir of the water measuring weir 3. The discharge of the weir plate 10 of the water measuring weir is very small compared with the discharge of the overflow weir 7 in a complete circle. By adjusting the opening of the valve 11 on the water supply pipeline 1, the lower limit Q of the flow from the water supply pipeline 1 min The flow rate entering the water measuring weir 3 is the flow rate required for the test. When the inflow suddenly increases, on the one hand, since the discharge of the weir plate 10 of the water measuring weir is very small compared with the discharge of the overflow weir 7 in a complete circle, and on the other hand, the weir plate 10 of the water measuring weir is far from the forebay 2 of the water measuring weir, while the overflow weir 7 is close to the forebay 2 of the water measuring weir, most of the extra flow will quickly discharge into the drainage channel 9 from the overflow weir 7, and the change range of the head over the weir of the weir plate 10 of the water measuring weir is small, that is, the flow rate fluctuation entering the water measuring weir 3 through the weir plate 10 of the water measuring weir is small, thus improving the problem of flow instability caused by unstable water supply.

Claims

1. A steady flow device for hydraulic model tests, characterized in that, It includes a weir. The inlet end of the weir is connected to the forebay of the weir, and the outlet end of the weir is connected to the forebay of the terrain. The other end of the forebay of the weir is internally connected to a water supply pipeline, and the water in the forebay of the terrain enters the test terrain through a steady flow flower wall.

2. The steady flow device for hydraulic model test according to claim 1, characterized in that, An overflow weir is provided on the side wall of the forebay of the weir. There are overflow weir grooves left at the four corners of the side wall of the forebay of the weir. Both sides of the overflow weir are inlaid in the overflow weir grooves. Drainage channels are arranged around the forebay of the weir, and drain outlets are provided at the bottom of the drainage channels.

3. The steady flow device for a hydraulic model test according to claim 2, characterized in that, The overflow weir is a segmented prefabricated overflow weir, with each segment being 1 cm high. The top elevations of the overflow weirs are basically level but slightly lower than the elevation of the head over the weir required for the weir.

4. The steady flow device for hydraulic model tests according to claim 1, wherein, A number of steady flow partitions are provided at the water inlet end of the weir. The length and width of the steady flow partitions are the same as those of the weir, and a plurality of water passing holes are arranged on the steady flow partitions.

5. The steady flow device for hydraulic model test according to claim 1, characterized in that, A weir plate is provided at the water outlet end of the weir, and the weir plate is a right-angled triangular weir.

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