TWM279657U - Downstream side pressure boundary control device for pipe flow of hydraulic model - Google Patents

Description

M279657 8. Description of new model: [Technical field to which the new model belongs] The new model relates to a downstream charging device that can control the downstream boundary pressure and flow rate by adjusting the pressure head at the downstream end of the hydraulic model tube flow. & [Previous technology] The total head at any point of the water flow in the pipe in the hydraulic model pipe flow is equal to Tan • The sum of the force head and the f-degree head; where the pressure head is equivalent to the high water level: 'It is proportional to the water level elevation; and the speed The head is inversely proportional to the area of the pipe flow. Once the setting of the boundary conditions at the downstream outlet is taken, the outlet flow is generally taken as the target, and the pressure and flow rate can be controlled. But in general, if ..J uses the valve opening size, that is, the official flow area as an operating variable, it can be used to control the speed head of the outlet. Because this method changes the size of the valve opening, Due to interference, the valve should be installed away from the control boundary, otherwise the flow field measurement near the downstream boundary will be affected; • 1 When the valve is used to control the downstream boundary, the pressure and flow rate cannot be adjusted correctly at the same time. In addition, it is often faced with the following difficulties when controlling downstream boundary conditions: 1. The flow of official flow is mainly controlled by the pressure difference between the upper and lower ends. If the pressure difference is too large, the valve opening degree will shrink and cause The outflow of water has great impulse, making boundary conditions difficult to control. And the valve needs to be far away from the control boundary. When the right site is restricted, it cannot provide enough pipe length to obtain the correct pipe flow condition. The downstream boundary can also be controlled by a fixed water level. This method is beneficial. 5 (§: M279657 uses a flat pool to make the water level reach the designed head. As the pipe flow directly enters a large water body to slow down its impact, and the boundary exits. The condition of non-atmospheric pressure is more in line with the pressure flow field in the pipe flow, and the range of influence on the flow field in the pipe is small, and there will be no trouble of increasing the beam shrinkage flow rate. However, the flat pool must be maintained to maintain the inflow and outflow. Equal, and make the upstream control boundary meet the requirements to determine the water level elevation of this flat pool. However, in order to reduce the impact of the water flow at the outlet of the pipe flow and not make the flat

The water surface of the pool fluctuates too much, and the volume of the water body of the flat pool needs to be increased. The flow rate and storage space need to be considered in the delta code. Although this method can control the downstream boundary more accurately, Too much space is expensive and not practical. 3. At the downstream boundary, energy dissipating methods can also be used to control, using various pipe diameters, f pipes and adjustable (can rise and fall) casings to connect to reduce the energy of the water flow and achieve the purpose of energy dissipation. The magnitude of energy dissipation y is calculated by reason, but the estimation of various loss coefficients varies with different inflows (Dan +,, and 4) in the upstream of the hydraulic model, making this configuration very difficult in practice. The cutting edge is difficult. In addition, the use of a sleeve to control the pressure is 7 megabytes. Although it can improve the lateral space, the heart and the peer can be improved, but the operation control of this rising and falling method is not easy. Excessive pressure can cause leaks or even damage. [New content] At this point, the purpose of this new model is to set border control at the downstream end. An adjustable hydraulic model is provided, which is the new hydraulic model tube, and the downstream boundary pressure control device 6 M279657 after six generations is installed on the downstream end mechanism of a hydraulic model. And contains a control tube and the control tube includes an inverted U-shaped camp

The Is body, and the ugly opposite ends of the official body, which extend in opposite directions along a pivot axis _ ^ τ < the water inlet end connected to the 忒 水工 枝 型 柩 and the water outlet end of 1 mesh. Ventilation holes are provided on the upper surface of the pipe top section of the pipe body to control the pressure of the pipe top section to be at atmospheric pressure. The crane mechanism is used to control the pipe body to rotate about the pivot axis to lie flat, tilt and stand upright.

[Embodiment] The features and effects of the foregoing and other technical contents of the present invention will be clearly shown in the following detailed description of a preferred embodiment in conjunction with the McCaw pattern. The preferred embodiment of the downstream pressure boundary control device of the novel hydraulic model pipe flow is installed at the downstream end of the hydraulic model 5 as shown in item i. The hydraulic model 5 includes a steep descent model 51 and a horizontal section model 52. As the experiment proceeds, the position of the steep-descent model 51 will maintain a fixed water level to observe the flow conditions in the horizontal section model 52. During implementation, the hydraulic head of the hydraulic model 5 has a relatively high upstream head. Usually, a water channel (not shown) is used to draw water into the hydraulic model 5 by a motor. After the water enters the steep drop model 51, the head height difference increases and the water flow speeds up. Will cause cavitation erosion on the channel structure of the steep drop model 51. Therefore, in the model 5 used in this embodiment, 'the gas flow is designed to make the water flow suffocate by designing the gas transport at the bottom of the steep drop 51 channel. Slow down its velocity and reduce the effects of pitting damage. However, the bubbles generated by radon in the water flow must enter the water turbine (not shown) for power generation in the future. 7 The exhaust pipe 5 3 is used to discharge. Therefore, the model $ 5 drops sharply at the end of M ^ 657 and is next to a horizontal section. Model 5 2 Φ 八 M r. ^ Used to separate air from water with its buoyancy. End of this new downstream pressure edge ® segment model 52. ~ Industrial system is installed at this level, as shown in Figures 2 and 3. The control is connected to # ~ 1 x 置 包 έ a 彳 彳 official 1, which is linked to the hydraulic model 5, and the mechanism is heavy. Support frame 3. Dan ^ and a control pipe 1 erected on the side of the control pipe 1 include an inverted U 丄 丄 A ^, is s body 11, in this embodiment is a

The rigid material made of plastic made of ethylene vinyl chloride (PVC), but it can also be an acrylic tube. The head end of the tube body 1 1 is connected to the end of the horizontal section model 5 and 2 through a Cossack swivel leakproof joint 16 and can define-the inlet end η and the opposite-the outlet end 3 extending direction Is the __ pivot axis μ. There is a water inlet at u — the meter 15 can measure the value of the pressure knife in the tube, and a downstream end of the water inlet 12 is provided with a hydraulic model that can be opened and closed to control the hydraulic model. The water enters the official body 1 1 The upper surface of the valve 14 〇 11 version 11 of the 11th edition, that is, to the back of the pipe body 11 in FIG. 2, is provided with a plurality of vent holes 110 on the upper surface. Refer to FIG. 4 for a cross section m-i [] of the top section 4 of the tube 11 of the lower body 11 in an upright shape. For example, U0 in this embodiment is set at 45 horizontal diameters. The position of the elevation angle and the positive top surface 'to prevent the 5 vent holes 110 from being covered by water when the official body 11 is tilted ", and: ττ achieves the effect of ventilation; however, the number and opening position are not limited to this, and a single pass can also be used. Air holes 11 〇, or axially spaced holes in the pipe top section 4. By this, the pressure of the free water surface in the pipe top section 4 of the official body 丨 丨 is maintained at a large atmospheric pressure. The pressure head of the water inlet 12 can be controlled by The water level inside the pipe at the top of the pipe 4 is controlled by the southward stroke. The force of the water # 12 can be read from the pressure gauge. The pipe at the water inlet 12 by M279657 is fixed, and the flow rate is fixed (steady fi0w). The lower pressure head can be controlled by the water level elevation of tube amount 4, and the boundary pressure of this swim end.

The fixed structure of the crane structure 2 is set at the next high point or side, which can be driven to put the pipe body U side down or pull up as shown in item 5, so that the pipe body ^ 11. The whole can be around the pivot axis 1G Tilt to _ limb angle, even close to water =. When the tube body 11 is inclined, the liquid level in the tube will be higher than the vent hole 110 ′ in the lower position. The vent hole 110 may be plugged with a plug (not shown). That is, 'the tilt angle of the control tube body 11 is controlled through the crane structure 2 and the I force of the top section 4 of the control tube is maintained to -atmospheric M through the vent hole 11G, that is, "the downstream pressure boundary of the hydraulic model is adjusted" "the goal of. In terms of actual tests, the experimental boundary conditions of the hydraulic model 5 were determined. After the upstream inflow is 9.65m3 / s, the water level of the steep drop model 51 is 391.84m. At 6 and 3m3 / s, the water level of the steep drop model 51 drops to 39,017 and 389,06m, respectively. The operation mode of the new control device is mainly as follows: 1)

The control tube body 11 is horizontal, and M 14 is fully opened. This step is to avoid blocking the water flow, causing imperial water and destroying the Model 5 channel. The upstream motor controls the release of a small flow so that the current flows from the steep-descent model 51 to the horizontal section model 52. 3) After the water flow in the horizontal section model 52 is stable, the pipe body 11 is slowly raised by driving the crane mechanism 2 as shown in Fig. 5 until the horizontal section model 52 is filled with water and stops lifting. 4) Increase the cast flow rate to a fixed flow rate for test control, and make the pipe body U follow M279657 to make the water level of the steep drop model 51 reach this flow rate, which is' the new model adjusts the Erli head by moving, "It is easy to model the water flow to reach the predetermined water level easily. 4 The steep drop J Na mentioned above 'Review of the previous hydraulic model ... Closed opening degree beam shrinkage = significant change in the local flow field near the gate #impact because:

: Force boundary control to set the earthquake, control the firm water head of the downstream plant to obtain the cover. Γ: Avoid changing the flow field of the water inlet end 12; the top section of the pipe ~ out: the end will form the energy dissipation effect of free falling water. The problem of large impulse at the Π end is also relieved by the setting of the control tube body η.

Continue to slowly raise the water level. However, the above is only a preferred embodiment of the present invention, and can be used to limit the scope of the new meticulous concept of Jintian 4 Dian M yoke, that is, according to the scope of the new application and the new description of meat six & Seeking equivalent changes and modifications between soaps made by Guei within the month from σσTμ, which is covered by the new patent. [Brief description of the drawings] FIG. 1 is a schematic diagram of a hydraulic model for creating a preferred embodiment of a downstream end boundary pressure control device; FIG. 2 is a schematic side view of the preferred embodiment; FIG. 3 Is a perspective view of the embodiment, illustrating the state of the control tube; 'FIG. 4 is a cross-sectional view taken along the line m-melon of FIG. 2; and FIG. 5 is a cross-sectional view taken along the IV-IV direction of FIG. 2, illustrating the implementation. Example of the state of control tube body tilt. 10 M279657 [Description of main component symbols] 1 · · • Control tube 16 · · · Leakproof joint 10 · · · Pivot shaft 2 · · · Crane structure 11 · · • Pipe body 3 · · • Support frame 110 · Ventilation 孑L 4 · · • Pipe top section 12 · · · Inlet end 5 · · · Hydraulic model 13 · · • Outlet end 51 · · • Descent model 14 · · • Valve 52 · · • Horizontal section model 15 · · • Manometer 53 ·· • Exhaust pipe 11

Claims (1)

M279657 9. Scope of patent application: 1. A hydraulic model tube flow t ^ Buju boundary pressure control device, downstream of the hydraulic model, and contains: 4 5 and one by one control tube, ¢ 7 h 7 t VL ^ — Inverted U-shaped pipe body 'and the entrance and exit rule of the opposite side of the water shaft and an opposite fighter * mountain and dust criminal drink that extend opposite to the axis of rotation of the second m area of the pipe body, and the pipe body is provided to the surface of the pipe at a height At least one ventilation hole; and another crane mechanism for controlling the tube body to tilt and stand upright M 4. ㈣… 柩 玄 柩 Axis pivot tilt 2 · According to the water pressure control described in item i of the scope of the patent application, it also contains ten, two ... youbian seven, ^ ° 3 wood ° and beside the control tube 4 'and for the crane structure to be fixed on it. 3. The downstream of the hydraulic model pipe flow according to Item 1 of the scope of the patent application, and the control force of the Poison Fortress is controlled, where 'the inlet end is provided-can be opened and closed to control the flow of water in the hydraulic model. The valve of the tube body. 4. According to the downstream boundary of the hydraulic model pipe flow described in item 1 of the scope of the patent application [Licai Industrial Equipment, Langzhong, there are a plurality of vent holes, and they are respectively opened at various positions on the top section of the pipe body of the pipe. And use a plug to plug the vent below the tube = water level. 5. The downstream boundary pressure control device of the hydraulic model pipe flow according to the patent scope of claim 4; the control pipe is made of polyethylene. 6. The downstream boundary pressure control device according to the hydraulic model pipe flow described in item 1 of the patent scope of Shenying, wherein the control pipe is an acrylic pipe. , 12