A water weir for measuring the performance test device, test method and construction method of a pump

Abstract

The present invention belongs to the technical field of pump performance detection, and provides a water weir for measuring pump performance test device, test method and construction method. The test device includes an inlet pool, an outlet pool, a vertical pump, a first measurement channel and a plurality of second measurement channels. The inlet end of the first measurement channel is communicated with the inlet pool, the outlet end is communicated with the outlet pool, and a horizontal pump is installed in the first measurement channel. n second measurement channels are arranged in parallel, the inlet end of the second measurement channel is communicated with the outlet pool, the outlet end is communicated with the inlet pool, and n≥2. The vertical pump is installed at the inlet end of the second measurement channel. The present invention adopts the first test channel and multiple second test channels. When conducting a pump performance test, the water flow can be introduced into one or more test channels according to the flow rate of the pump, thereby increasing the test range of the test device and enabling the measurement of pumps with ultra-large flow rates and low lift heights.

Description

Technical Field

[0001] The present invention belongs to the technical field of pump performance detection, and particularly relates to a water weir for measuring pump performance test device, test method and construction method. Background Art

[0002] There are many methods for measuring pump flow. Especially with the development of electronic technology, a large number of new technologies and new products such as electromagnetic flow meters and ultrasonic flow meters are applied to the pump test technology field. However, these flow measurement methods have limitations in scale. For some large-flow and super-large-flow pumps, especially in the water conservancy industry, the pump flow is extremely large, reaching dozens of tons per second or even more. It is impossible to measure the pump flow with these flow meters usually installed on pipelines. The water weir method is a method based on the basic principles of fluid mechanics, which calculates the fluid flow by measuring the water head of the water flowing through a specific device.

[0003] The water weir method has been widely used in water conservancy project measurements such as channels, reservoirs, water canals and flood drainage ditches. However, in large pump manufacturing enterprises, there are relatively few test devices for measuring such large water pumps. Especially, such pump test devices cover a large area and require a large amount of investment. The existing water weir method measurement devices have limited applicable measurement ranges and low measurement accuracies. There are also existing water weir method measurement devices with relatively large liquid level differences and flow resistances at the pump inlet and outlet, and they cannot measure some super-large-flow and low-lift pumps. Summary of the Invention

[0004] In order to solve the problems in the background art, the present invention proposes a water weir for measuring pump performance test device, test method and construction method.

[0005] In order to achieve the above object, the present invention adopts the following technical solutions:

[0006] A water weir for measuring pump performance test device includes a water inlet tank, a water outlet tank, a vertical pump, a first measurement channel, a weir and a plurality of second measurement channels;

[0007] The inlet end of the first measurement channel is communicated with the water inlet tank, the outlet end is communicated with the water outlet tank, and a horizontal pump is installed in the first measurement channel;

[0008] n second measurement channels are arranged in parallel, and the inlet end of the second measurement channel is communicated with the water outlet tank, the outlet end is communicated with the water inlet tank, n≥2;

[0009] The vertical pump is installed on one side of the inlet end of the second measurement channel for pumping water from the water inlet tank and conveying it to the corresponding second measurement channel;

[0010] A third gate is installed at the inlet end of each second measurement channel, and the third gate is located on one side of the vertical pump;

[0011] The weir is installed at the outlet end of the second measurement channel.

[0012] Preferably, the first measurement channel further includes an inlet water flow channel, a first gate, a first reducing flange, a second reducing flange, a second gate, and an outlet water flow channel;

[0013] Along the water flow direction, the inlet water flow channel, the first gate, the first reducing flange, the horizontal pump, the second reducing flange, the second gate, and the outlet water flow channel are connected in sequence.

[0014] Preferably, along the water flow direction:

[0015] The inlet water flow channel is of a tapered structure;

[0016] The outlet water flow channel is of a diffusive structure.

[0017] Preferably, the second measurement channel is a weir tank;

[0018] Along the first direction, the vertical pump is installed at the inlet end of the weir tank, and the weir tank is of a linear structure;

[0019] Along the second direction perpendicular to the first direction, the third gate is installed at the end of the tank wall of the first weir tank closest to the water outlet pool, and the first weir tank is the weir tank closest to the water outlet pool;

[0020] Along the second direction, the adjacent weir tanks share a common tank wall, and the third gate is installed at the end of the shared tank wall.

[0021] Preferably, a weir plate and a rectifying grid are installed on the bottom plate of the weir tank;

[0022] The weir plate is installed on the bottom plate at the outlet end of the weir tank, and both ends of the weir plate are in contact with the tank walls of the weir tank respectively;

[0023] The weir plate is the weir of the second measurement channel, and the area above the top of the weir plate is the weir top;

[0024] The rectifying grid is installed on the bottom plate at the inlet end of the weir tank.

[0025] Preferably, the vertical pump is provided with a suction pipe and a discharge pipe;

[0026] The suction pipe is located in the inlet water pool, and the discharge pipe is located on one side of the inlet end of the second measurement channel.

[0027] Preferably, the inlet water pool is also communicated with a regulating water pool.

[0028] Preferably, two second measurement channels are provided.

[0029] A water weir measuring pump performance test method, applied to the above-mentioned water weir measuring pump performance test device, comprises the following steps:

[0030] The first measuring channel, the water outlet pool and the m second measuring channels are kept connected, and the flow rate of the horizontal pump is tested by the liquid level heights of the m second measuring channels, where n≥m≥1;

[0031] Or, the first measuring channel is closed and the adjacent second measuring channel is isolated by a third gate, water from the water inlet pool is pumped out by a single vertical pump and delivered to a single second measuring channel, and then the flow rate of the single vertical pump is measured by the liquid level height of the single second measuring channel;

[0032] Alternatively, close the first measuring channel and control the third gate to connect the k second measuring channels, draw water from the water inlet pool through a single vertical pump and deliver it to the k second measuring channels, and then measure the flow rate of the single vertical pump through the liquid level heights of the k second measuring channels, n≥k≥1.

[0033] Preferably, the flow rate formula is as follows:

[0034] Q=C d ×2 / 3×(2×g) 1 / 2 ×b×h 3 / 2 ;

[0035] In the formula, the flow coefficient C d =0.602+0.075×h / E; h is the water head on the weir of the second measuring channel, in m; E is the height of the weir of the second measuring channel; g is the acceleration of gravity; b is the width of the weir used.

[0036] Preferably: when the flow rate of the horizontal pump is 15.3m 3 / s≤Q≤30.6m 3 / s, m=2;

[0037] When the flow rate of the horizontal pump is 3.05m 3 / s≤Q≤15.3m 3 / s, m=1;

[0038] When the flow rate of the vertical pump is 3.05m 3 / s≤Q≤15.3m 3 / s, k=1;

[0039] When the flow rate of the vertical pump is 15.3m 3 / s≤Q≤30.6m 3 / s, k=2.

[0040] A construction method for the above-mentioned weir pump performance test device comprises the following steps:

[0041] Set the maximum flow rate of the pump to be tested and the design head of the weir, where the pump to be tested is a horizontal pump or a vertical pump;

[0042] Calculate the width of the weir based on the maximum flow rate of the pump to be tested and the design head of the weir;

[0043] Set the number and length of the second measurement channels based on the width of the weir.

[0044] Preferably, the width of the weir calculated based on the maximum flow rate of the pump to be tested and the design head of the weir satisfies:

[0045] Q 设定 =C d ×2 / 3×(2×g) 1 / 2 ×b1×h 设定 3 / 2 ;

[0046] In the formula, the flow coefficient Cd = 0.602 + 0.075×h 设定 / E; h 设定 is the head above the weir of the second measurement channel set, E is the height of the weir of the second measurement channel; g is the acceleration due to gravity; b1 is the width of the weir during measurement; Q 设定 is the maximum flow rate of the pump to be tested set.

[0047] Preferably, the length of the second measurement channel is greater than ten times the width of the weir.

[0048] Advantages of the present invention:

[0049] 1. The present invention adopts the first test channel and multiple second test channels. When conducting the pump performance test, the water flow can be introduced into one or more test channels according to the flow rate of the pump, thereby increasing the test range of the test device and enabling the measurement of pumps with ultra-large flow rates and low head;

[0050] 2. The test method of the present invention arranges the parallel weir channels above the connected water storage tank (intake tank + regulating tank), and through the combined design with the gate, the test device can be used to test horizontal pumps and vertical pumps, expanding the use of the test device, greatly reducing the floor area of the test device, and at the same time reducing the earthwork excavation volume and lowering the construction cost of the test device.

[0051] 3. The single and double weir measurement modes designed by the construction method of the present invention broaden the flow rate range of pump testing, and at the same time, through calculation, the single and double weirs are reasonably allocated, making the test results more accurate.

[0052] Other features and advantages of the present invention will be set forth in the following description, and in part will be obvious from the description, or may be learned by practice of the present invention. The objectives and other advantages of the present invention may be realized and attained by the structure particularly pointed out in the specification and the drawings. Description of the Drawings

[0053] In order to more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following briefly introduces the drawings required for use in the description of the embodiments or the prior art. Obviously, the drawings in the following description are some embodiments of the present invention. For those of ordinary skill in the art, other drawings can be obtained based on these drawings without creative efforts.

[0054] Figure 1 Shows a top view of a water weir measuring pump performance test device of the present invention;

[0055] Figure 2 Shows a structural diagram under the weir trough of a water weir measuring pump performance test device of the present invention;

[0056] Figure 3 Shows a flowchart of a water weir measuring pump performance test method of the present invention;

[0057] Figure 4 Shows a flowchart of a construction method of the present invention.

[0058] In the figure: 1, intake sump; 2, intake flow channel; 3, first gate; 4, first reducing flange; 5, horizontal pump; 6, second reducing flange; 7, second gate; 8, outlet flow channel; 9, discharge sump; 10, third gate; 11, weir plate; 12, vertical pump; 1201, extraction pipe; 1202, discharge pipe; 13, regulating sump; 14, straightening grid; 15, weir trough. Detailed Embodiments

[0059] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the following clearly and completely describes the technical solutions in the embodiments of the present invention with reference to the drawings in the embodiments of the present invention. Obviously, the described embodiments are some, but not all, of the embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts fall within the scope of protection of the present invention.

[0060] A test device for measuring the performance of a pump in a water weir is composed of an intake sump 1, a discharge sump 9, a vertical pump 12, a first measurement channel, a weir, and several second measurement channels.

[0061] The inlet end of the first measuring channel is connected to the water inlet pool 1, and the outlet end is connected to the water outlet pool 9, and a horizontal pump 5 is installed in the channel. There are n second measuring channels (n≥2), and they are arranged in parallel. The inlet end of each second measuring channel is connected to the water outlet pool 9, and the outlet end is connected to the water inlet pool 1. The vertical pump 12 is arranged on one side of the inlet end of the second measuring channel, and its function is to extract water from the water inlet pool 1 and transport the water to the corresponding second measuring channel. The weir is installed at the outlet end of the second measuring channel; in addition, the inlet end of each second measuring channel is installed with a third gate 10, which is located on one side of the vertical pump 12. The third gate 10 can control the opening and closing between the water outlet pool 9 and the corresponding second measuring channel, and can also isolate each second measuring channel.

[0062] Combine the following Figure 1 and Figure 2 The above structure is further described, wherein n=2, so there are two second measurement channels in total.

[0063] like Figure 1 As shown, the first measuring channel includes an inlet channel 2, a first gate 3, a first reducing flange 4, a horizontal pump 5, a second reducing flange 6, a second gate 7 and an outlet channel 8. Along the flow direction of the medium, the components are connected in sequence, specifically: the inlet channel 2 is in the front, followed by the first gate 3, the first reducing flange 4, the horizontal pump 5, the second reducing flange 6, the second gate 7, and the outlet channel 8 is at the end.

[0064] In addition, along the medium flow path, the inner diameter of the water inlet channel 2 gradually decreases, which is a tapered structure; the inner diameter of the outlet channel 8 gradually increases, which is a diffusion type; the inner diameter of the first variable diameter flange 4 also changes from large to small (or adopts a constant diameter structure), and the inner diameter of the second variable diameter flange 6 gradually increases from a smaller size (or adopts a constant diameter structure). This inner diameter change design plays a key role in regulating the flow rate and pressure of the medium in the channel, and thus affects the accuracy and stability of the entire pump performance test.

[0065] like Figure 1 As shown, the second measuring channel is a weir groove 15. Figure 1 In the horizontal direction, i.e., the first direction, the vertical pump 12 is installed at the inlet of the weir groove 15, and the weir groove 15 is in a linear structure as a whole. In the second direction perpendicular to the first direction, the third gate 10 is installed at the end of the groove wall of the first weir groove 15 close to the outlet pool 9, and the first weir groove 15 is the weir groove 15 closest to the outlet pool 9; in the second direction, the adjacent weir grooves 15 share the groove wall, and the third gate 10 is installed at the end of the shared groove wall. When viewed along the second direction, the outlet pool 9 and the weir groove 15 are connected to each other.

[0066] It should be noted that Figure 1It can be seen from the structure that the two weirs 15 are arranged in parallel, and the distances between each weir 15 and the outlet pool 9 are different. Among them, the weir 15 closest to the outlet pool 9 needs to be installed with a third gate 10 between it and the outlet pool 9 to control the opening and closing of the weir 15. For the second weir 15, another third gate 10 needs to be installed between it and the first weir 15, and this gate can adjust the on-off state between the two adjacent weirs 15. When the second third gate 10 is closed, it actually has the effect of extending the wall of the weir 15, and its function is to separate the adjacent weirs 15 from each other. In addition, the vertical pump 12 has a stable pumping capacity and can always pump water from the inlet pool 1 into the weir 15. The opening and closing state of the third gate 10 will not affect the pumping operation of the vertical pump 12.

[0067] Furthermore, a weir plate 11 and a rectifying grid 14 are installed at the bottom of the weir groove 15. The weir plate 11 is located on the bottom plate at the outlet end of the weir groove 15. It serves as the weir of the second measurement channel. The weir plate 11 can form a water tongue at the outlet position of the weir groove 15. The formation of the water tongue helps to establish a stable relationship between water head and flow. When the water flows through the weir plate 11 to form a water tongue, the water flow shape is relatively stable. According to relevant hydraulic principles and formulas, by measuring parameters such as the water head on the weir (i.e., the vertical distance from the top of the water tongue to the top of the weir plate 11), the flow rate of the water flow can be calculated more accurately. The rectifying grid 14 is located on the bottom plate at the inlet end of the weir groove 15, which can rectify the water flow flowing into the weir groove 15.

[0068] It should be noted that the top of the weir plate 11 is the weir mouth, and the area above the weir mouth is the upper weir area.

[0069] like Figure 2 As shown, the vertical pump 12 is provided with an extraction pipe 1201 and a discharge pipe 1202, wherein the extraction pipe 1201 is located in the water inlet tank 1, and the discharge pipe 1202 is located at the inlet of the second measuring channel. Therefore, when the vertical pump 12 is working, water can be drawn from the water inlet tank 1 through the extraction pipe 1201 at the bottom, and then delivered to the weir 15 through the discharge pipe 1202.

[0070] Combination Figure 1 and Figure 2 It can be seen that the water inlet pool 1 is also connected to a regulating water pool 13. The regulating water pool 13 is Figure 1 The outside of the neutral pump 12 and the bottom are connected with the water inlet pool 1, and the two are equivalent to a communicating vessel. When the amount of water in the water inlet pool 1 decreases, the regulating water pool 13 can replenish water to the water inlet pool 1 to avoid the water level of the water inlet pool 1 being too low. Conversely, when the amount of water in the water inlet pool 1 increases, the regulating water pool 13 can prevent the water level of the water inlet pool 1 from being too high or increasing too fast.

[0071] It should be noted that Figure 1 and Figure 2The device arranges two parallel weirs 15 above the interconnected water storage tank (water inlet tank 1 + regulating water tank 13), and through the combined design with the gate, the test device can be used to test the horizontal pump 5 and the vertical pump 12, which expands the use of the test device, greatly reduces the floor space of the test device, and also reduces the amount of earth excavation, thereby reducing the construction cost of the test device.

[0072] like Figure 3 As shown, a water weir measuring pump performance test method is applied to the above-mentioned water weir measuring pump performance test device, which can perform any steps S1-S3 according to the situation, as follows:

[0073] S1: Keep the first measuring channel, the water outlet pool 9 and the m second measuring channels connected, and test the flow rate of the horizontal pump 5 through the liquid level heights of the m second measuring channels, n≥m≥1.

[0074] S2: The first measuring channel is closed and the adjacent second measuring channel is isolated by the third gate 10, and the water of the water inlet pool 1 is pumped by the single vertical pump 12 and transported to the single second measuring channel, and then the flow rate of the single vertical pump 12 is measured by the liquid level height of the single second measuring channel;

[0075] S3: Close the first measuring channel and control the third gate to connect the k second measuring channels, draw water from the water inlet pool 1 through a single vertical pump 12 and transport it to the k second measuring channels, and then measure the flow rate of the single vertical pump 12 through the liquid level height of the k second measuring channels, n≥k≥1.

[0076] It should be noted that, through the above steps, it can be known that the first measurement channel and the second measurement channel of the present invention need to work together when conducting the test. In the entire process of the water flow (the path of the first measurement channel + the outlet pool 9 + the second measurement channel), the water flow will generate resistance, and the horizontal pump 5 or the vertical pump 12 being tested must not only overcome the resistance, but also overcome the force required for the water flow to be lifted from the inlet pool 1 and submerge the weir of the second measurement channel (i.e., the weir plate 11 in the weir groove 15). Therefore, it is necessary to measure the minimum head of the horizontal pump 5 and the vertical pump 12, and at the same time, it is necessary to measure the water flow rate drawn from the inlet pool 1 (to determine the pump flow rate).

[0077] The water weir pump performance test method is described below in conjunction with the specific flow rates of the horizontal pump 5 and the vertical pump 12 .

[0078] For example, when the flow rate of horizontal pump 5 is 15.3m 3 / s≤Q≤30.6m 3When the flow rate is / s, n = 2 and m = 2. At this time, the first gate 3, the second gate 7 and all the third gates 10 can be opened (at this time, there are two parallel weir channels 15, so there are two third gates 10 in total). During operation, the horizontal pump 5 can pump water from the inlet pool 1 and transport it to the outlet pool 9. Then, the water in the outlet pool 9 enters the two parallel weir channels 15, and finally, the minimum lift of the horizontal pump 5 is calculated by observing the liquid level height in the weir channels 15.

[0079] When measuring the minimum lift:

[0080] Taking the maximum flow rate of 30m 3 / s as an example, the total area of the pool and the weir channel 15 is A 总 = 1226.4m 2 (including the regulating area of the regulating pool 13). The volume of the water head above the weir (on the weir channel 15) at the maximum flow rate is:

[0081] V 堰上 = b × L 堰槽 × h = 772.3m 3 ; (1)

[0082] In the formula, b is the width of the weir used; h is the height from the weir opening to the top of the water tongue above the weir (i.e., the water head above the weir), where the weir opening is the top of the weir plate 11; L is the length of the weir channel 15.

[0083] It should be noted that the surface corresponding to the width of the weir is the surface that bears the direct impact of the water flow, which corresponds to Figure 1 the surface perpendicular to the water flow direction in. In addition, not all the weir channels 15 will be used during measurement, so b should be calculated for the used weir plates 11. In addition, when calculating the width of the used weir, if the second measurement channel is one, only the width of the weir plate 11 in this channel is calculated, and if there are multiple channels, the total width of the weir plates 11 in multiple channels is calculated.

[0084] The volume of the pool when the water level drops from the edge to the bottom of the weir channel 15 is V 堰底 = 613.5m 3 , so the water level drop below the weir plate 11 at the maximum flow rate is:

[0085] ⊿H 堰下 = (V 堰上+ V 堰底 ) / A 总 = 1.13m; (2)

[0086] The total resistance drop ∑h at the maximum flow rate is obtained through formulas (1) and (2) ƒ = ⊿H 堰下 + h f = 1.4m, where h f see formula (5).

[0087] From the above calculation process, it can be seen that the lowest head that can be measured by the pump under test at the maximum flow rate can be obtained from the fact that the head of the pump under test must be greater than the total resistance drop. Similarly, the lowest measured head corresponding to each flow rate point can be calculated. This makes the lowest head that can be measured by this test device lower, solves the problem that it is difficult to test large-flow and low-head pumps, and also broadens the test range of the performance parameters of large pumps by the weir test.

[0088] It should be noted that when testing large-flow and low-head pumps, the water in the regulating pool 13 can be directed to the inlet pool 1 to reduce the water level difference in the inlet pool 1; at the same time, the contraction angle of the inlet flow channel 2 is designed to be 8°, and the diffusion angle of the outlet flow channel 8 is designed to be 10° to reduce the frictional loss along the inlet and outlet flow channels 8 of the pump. In this way, according to the fluid energy equation, it can be seen that the lowest head of the measured pump can be minimized.

[0089] When measuring the flow rate:

[0090] The following takes the horizontal pump 5 with a maximum flow rate of 30 m 3 / s combined with two weir troughs 15 as an example to illustrate its design process.

[0091] (1) Set the maximum flow rate of the horizontal pump 5 to 30 m 3 / s, design the maximum head h of the full-width weir max = 1.5 m, and according to engineering experience, take the designed head h on the weir d = 0.8h max = 1.2 m.

[0092] (2) According to the full-width weir flow rate calculation formula:

[0093] Q = C d × 2 / 3 × (2 × g) 1 / 2 × b × h 3 / 2 ; (3)

[0094] In the formula, the flow coefficient C d = 0.602 + 0.075 × h / E, where h is the head on the weir of the second measurement channel (i.e., the weir trough 15), in m; E is the height of the weir (i.e., the weir plate 11) of the second measurement channel, both in m. The gravitational acceleration g = 9.81. Substituting the values, the width b of the measurement weir is calculated to be 10.82 ≈ 11 m, and the length of the designed weir trough 15 is 65 m. Also, from the condition for the formation of the water tongue, it can be known that the minimum head h on the weir min = 0.44 m. Substituting the above flow rate calculation formula, the minimum and maximum measurement flow rates of a single weir are 3.05 m 3 / s and 15.3 m 3 / s respectively.

[0095] Therefore, when measuring the minimum lift, the combination of weir channels 15 can be reasonably allocated according to the flow rate of the pump to be measured for the test, which can make the measurement accuracy higher.

[0096] It should be noted that during the design process, different relationships between the Chezy coefficient C, the channel resistance coefficient λ, and the channel roughness coefficient n also need to be considered, such as:

[0097] C = R 1 / 6 / n, λ = 8×g / C 2 ; (4)

[0098] The formula for calculating the frictional resistance of the water flow along the weir channel 15 is summarized as:

[0099] h ƒ = L×ν 2 ×N 2 ×(1 / h + 2 / b) 4 / 3 ; (5)

[0100] Among them, h f represents the head loss of the water flow along the flow path, with the unit of m; the flow path is the length of the water flow from the inlet of the first measurement channel to the outlet of the second measurement channel; L is the flow path; ν is the flow velocity of the water flow; N represents the roughness coefficient of the second measurement channel.

[0101] The hydraulic radius R = A / x = b×h / (b + 2h), where A is the cross-sectional area of the water flow, with the unit of m 2 , x is the wetted perimeter of the cross-sectional area of the water flow and the weir channel 15, and x = 2h + b, with the unit of m.

[0102] According to the above formulas (3)-(5), the channel design can be optimized, and the flow velocity can be reduced to minimize the frictional resistance of the measuring weir. At the same time, the unique regulating pool is used to reduce the liquid level difference ⊿H between the inlet pool and the outlet pool under the measured flow rate, so that the total resistance drop ∑h ƒ = h ƒ + ⊿H is minimized.

[0103] For example, when the flow rate of the horizontal pump 5 is 3.05m 3 / s ≤ Q ≤ 15.3m 3 / s, n = 2, m = 1. At this time, the first gate 3, the second gate 7, and the third gate 10 of the weir channel 15 closest to the outlet pool 9 can be opened. During operation, the horizontal pump 5 can pump water from the inlet pool 1 and transport it to the outlet pool 9, then the water in the outlet pool 9 enters the weir channel 15 closest to the outlet pool 9, and finally, the flow rate and the minimum lift of the horizontal pump 5 can be calculated by observing the liquid level height of the weir channel 15.

[0104] For example, when the flow rate of the vertical pump 12 is 3.05m 3 / s ≤ Q ≤ 15.3m 3When it is / s, n = 2. At this time, the first measurement channel is closed and the adjacent weir tank 15 is separated by the third gate 10. The water in the inlet sump 1 is pumped by the single vertical pump 12 and conveyed to the single weir tank 15. Then, the flow rate and the minimum lift of the single vertical pump 12 are measured by measuring the liquid level height of the single weir tank 15.

[0105] For example, when the flow rate of the vertical pump 12 is 15.3 m 3 / s ≤ Q ≤ 30.6 m 3 / s, n = 2, k = 2. At this time, the first measurement channel can be closed and the third gate 10 between the two weir tanks 15 is opened to ensure that the two weir tanks 15 are interconnected at the inlet end (the third gate between the first weir tank 15 and the outlet sump 9 is not opened). Then, the single vertical pump 12 pumps the water in the inlet sump 1 and conveys the water to the two second measurement channels. Then, the flow rate and the minimum lift of the single vertical pump 12 are measured by measuring the liquid level heights of the two second measurement channels.

[0106] As Figure 4 shown, it is a construction method that can calculate the size of the weir tank 15 according to the flow rate, specifically as follows:

[0107] A1: Set the maximum flow rate of the pump to be tested and the design head of the weir. The pump to be tested is the horizontal pump 5 or the vertical pump 12;

[0108] A2: Calculate the width of the weir based on the maximum flow rate of the pump to be tested and the design head of the weir. The calculation formula is as follows:

[0109] Q 设定 = C d × 2 / 3 × (2 × g) 1 / 2 × b1 × h 设定 3 / 2 ; (6)

[0110] In the formula, the flow coefficient Cd = 0.602 + 0.075 × h 设定 / E; h 设定 is the head over the weir of the set second measurement channel, E is the height of the weir of the second measurement channel; g is the acceleration due to gravity; b1 is the width of the weir during measurement; Q 设定 is the set maximum flow rate of the pump to be tested.

[0111] A3: Set the number and length of the second measurement channels based on the width of the weir. The length of the second measurement channel is greater than ten times the width of the weir.

[0112] It should be noted that in the above design process, two parallel weir channels 15 are arranged above the connected water storage tank (intake tank 1 + regulating tank 13), and through the combined design with the gate, the test device can be used to test the horizontal pump 5 and the vertical pump 12, expanding the use of the test device, greatly reducing the floor area of the test device, and at the same time reducing the earthwork excavation volume and lowering the construction cost of the test device.

[0113] Combined Figures 1 - 4 , the single and double weir measurement modes designed by the construction method of the present invention broaden the flow range of pump testing. At the same time, through calculation, the single and double weirs are reasonably allocated, making the test results more accurate. Secondly, the designed unique regulating tank 13 and water circulation system greatly reduce the water level difference and flow resistance at the inlet and outlet when testing the pump, enabling a lower testable head and broadening the range of pump test performance parameters, solving the problem of difficult testing for pumps with ultra-large flow and extremely low head. Finally, the water weir method pump test device is built through the combined design of flow channels in a limited space, meeting the performance test requirements of different pump types such as horizontal and vertical pumps, expanding the use of the test device, and greatly saving the land resources and construction costs of factories and enterprises.

[0114] Although the present invention has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that: they can still modify the technical solutions described in the foregoing embodiments, or perform equivalent replacements for some of the technical features; and these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A water weir pump performance test device, characterized in that: It comprises a water inlet pool (1), a water outlet pool (9), a vertical pump (12), a first measuring channel, a weir and a plurality of second measuring channels; The inlet end of the first measuring channel is in communication with the water inlet pool (1), and the outlet end is in communication with the water outlet pool (9), and a horizontal pump (5) is installed in the first measuring channel; n second measurement channels are arranged in parallel, and the inlet end of the second measurement channel is connected to the water outlet pool (9), and the outlet end is connected to the water inlet pool (1), and n≥2; The vertical pump (12) is installed on one side of the inlet end of the second measuring channel, and is used to draw water from the water inlet pool (1) and transport it to the corresponding second measuring channel; A third gate (10) is installed at the inlet end of each of the second measuring channels, and the third gate is located on one side of the vertical pump (12); The weir is installed at the outlet end of the second measurement channel.

2. A water weir measuring pump performance test device according to claim 1, characterized in that: The first measuring channel further comprises a water inlet channel (2), a first gate (3), a first reducing flange (4), a second reducing flange (6), a second gate (7) and an outlet channel (8); Along the water flow direction, the water inlet channel (2), the first gate (3), the first reducing flange (4), the horizontal pump (5), the second reducing flange (6), the second gate (7) and the outlet channel (8) are connected in sequence.

3. A water weir measuring pump performance test device according to claim 2, characterized in that: Along the flow direction: The water inlet channel (2) is a tapered structure; The outlet flow channel (8) is a diffusion structure.

4. A water weir measuring pump performance test device according to claim 1, characterized in that: The second measuring channel is a weir (15); Along the first direction, the vertical pump (12) is installed at the inlet end of the weir groove (15), and the weir groove (15) is a linear structure; Along a second direction perpendicular to the first direction, the third gate (10) is installed at the end of the groove wall of the first weir groove (15) closest to the water outlet pool (9), and the first weir groove (15) is the weir groove (15) closest to the water outlet pool (9); Along the second direction, adjacent weir grooves (15) share a groove wall, and the third gate (10) is installed at the end of the shared groove wall.

5. A water weir measuring pump performance test device according to claim 4, characterized in that: The bottom plate of the weir groove (15) is provided with a weir plate (11) and a rectifying grid (14); The weir plate (11) is mounted on the bottom plate at the outlet end of the weir groove (15), and both ends of the weir plate (11) are respectively against the groove wall of the weir groove (15); The weir plate (11) is a weir of the second measuring channel, and the area above the top of the weir plate (11) is the upper weir; The rectifying grid (14) is mounted on the bottom plate at the inlet end of the weir (15).

6. A water weir measuring pump performance test device according to claim 1, characterized in that: The vertical pump (12) is provided with an extraction pipe (1201) and a discharge pipe (1202); The extraction pipe (1201) is located in the water inlet pool (1), and the discharge pipe (1202) is located on one side of the inlet end of the second measurement channel.

7. A water weir measuring pump performance test device according to any one of claims 1 to 6, characterized in that: The water inlet pool (1) is also connected to a regulating water pool (13).

8. A water weir pump performance test device according to any one of claims 1 to 6, characterized in that: Two second measurement channels are provided.

9. A water weir measuring pump performance test method, applied to a water weir measuring pump performance test device according to any one of claims 1 to 8, characterized in that: The following steps are involved: The first measuring channel, the water outlet pool (9) and the m second measuring channels are kept in communication, and the flow rate of the horizontal pump (5) is tested by the liquid level heights of the m second measuring channels, where n≥m≥1; Alternatively, the first measuring channel is closed and the adjacent second measuring channel is isolated by a third gate (10), water from the water inlet pool (1) is pumped by a single vertical pump (12) and transported to a single second measuring channel, and the flow rate of the single vertical pump (12) is measured by the liquid level height of the single second measuring channel; Alternatively, the first measuring channel is closed and the third gate is controlled to connect the k second measuring channels, water is drawn from the water inlet pool (1) by a single vertical pump (12) and delivered to the k second measuring channels, and the flow rate of the single vertical pump (12) is then measured by the liquid level heights of the k second measuring channels, where n≥k≥1.

10. A water weir measuring pump performance test method according to claim 9, characterized in that: The flow rate formula is as follows: Q=C d ×2 / 3×(2×g) 1 / 2 ×b×h 3 / 2 ; In the formula, the flow coefficient C d =0.602+0.075×h / E; h is the water head on the weir of the second measuring channel, in m; E is the height of the weir of the second measuring channel; g is the acceleration of gravity; b is the width of the weir used.

11. A water weir pump performance test method according to claim 9, characterized in that: When the flow rate of the horizontal pump (5) is 15.3m 3 / s≤Q≤30.6m 3 / s, m=2; When the flow rate of the horizontal pump (5) is 3.05m 3 / s≤Q≤15.3m 3 / s, m=1; When the flow rate of the vertical pump (12) is 3.05m 3 / s≤Q≤15.3m 3 / s, k=1; When the flow rate of the vertical pump (12) is 15.3m 3 / s≤Q≤30.6m 3 / s, k=2.

12. A construction method for constructing a water weir measuring pump performance test device according to any one of claims 1 to 8, characterized in that: The following steps are involved: Setting the maximum flow rate of the pump to be tested and the design water head of the weir, wherein the pump to be tested is a horizontal pump (5) or a vertical pump (12); Calculate the width of the weir based on the maximum flow of the pump to be tested and the design head of the weir; The number of second measurement channels and the length of the second measurement channels are set based on the width of the weir.

13. A construction method according to claim 12, characterized in that: The width of the weir is calculated based on the maximum flow of the pump to be tested and the design head of the weir to meet the following requirements: Q 设定 =C d ×2 / 3×(2×g) 1 / 2 ×b1×h 设定 3 / 2 ; In the formula, the flow coefficient Cd = 0.602 + 0.075 × h 设定 / E;h 设定 is the water head on the weir of the second measurement channel, E is the height of the weir of the second measurement channel; g is the acceleration of gravity; b1 is the width of the weir during measurement; Q 设定 is the maximum flow rate of the pump to be tested.

14. A construction method according to claim 13, characterized in that: The length of the second measuring channel is greater than ten times the weir width.

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