Centrifugal pump synergistic drag reduction, noise reduction and vibration reduction device and control method thereof

Abstract

The present application belongs to the technical field of noise and vibration control, and discloses a kind of centrifugal pump synergic drag reduction noise reduction and vibration reduction device and control method, centrifugal pump is connected static mixer by first pressure sensor, static mixer is connected liquid storage tank by test pipeline, and liquid storage tank is connected centrifugal pump by electromagnetic flowmeter and second pressure sensor in turn;Precise metering pump injects high concentration of drag reduction agent stock solution into static mixer uniformly mixed according to set flow;Acceleration sensor, microphone, laser tachometer respectively collect the vibration, radiation noise, rotational speed of centrifugal pump;After precise metering pump is configured drag reduction agent solution, the output frequency of frequency converter is adjusted to reduce the rotational speed of centrifugal pump, so that the flow of centrifugal pump recovers to preset target flow.The present application can measure the influence of drag reduction agent on water power, vibration and noise simultaneously in complex pump-pipeline system, and avoid operating point drift through constant current synergic control, realize drag reduction noise reduction and vibration reduction synergic efficiency.

Description

Technical Field

[0001] This invention belongs to the field of noise and vibration control technology. Specifically, it relates to a synergistic device and its control method that can simultaneously achieve drag reduction, noise reduction and vibration reduction without changing the pump and pipeline structure. Background Technology

[0002] Centrifugal pumps, as core equipment in industrial fluid transport systems, are widely used in petroleum, chemical, power, and municipal water supply industries. However, centrifugal pumps generally suffer from high energy consumption and significant vibration and noise during operation. Vibration and noise not only shorten equipment lifespan and reduce operational stability due to component fatigue, but also deteriorate the working environment. Statistics show that pump systems account for more than 20% of total industrial energy consumption; therefore, improving the efficiency and vibration / noise performance of centrifugal pumps has significant engineering value and economic benefits.

[0003] Currently, the main technical approaches to improving centrifugal pump performance focus on structural optimization, such as optimizing blade geometry parameters (e.g., outlet angle, wrap angle, number of blades), adopting biomimetic surface textures, improving pressure chamber design, and setting up flow guiding structures. While these methods have achieved some success, they often require modifications during the design and manufacturing stages, resulting in long development cycles, high costs, and difficulty in applying them to retrofitting existing pump units. Furthermore, structural optimization methods often require trade-offs between different performance indicators, making it difficult to achieve synergistic improvements in drag reduction, noise reduction, and vibration reduction.

[0004] In recent years, fluid modification technology has provided new insights into improving pump performance. Adding trace amounts of drag-reducing agents to a fluid can suppress near-wall turbulent pulsations and significantly reduce flow resistance. These agents reduce frictional resistance by forming viscoelastic microstructures that inhibit turbulent bursts and the development of coherent structures. For pump systems, the drag-reduction effect reduces the power required to deliver the same flow rate, allowing the pump to operate at lower speeds, thus simultaneously suppressing turbulent and mechanical noise.

[0005] However, most existing experimental setups are limited to measuring the drag-reducing effect of drag-reducing agents in simple straight pipes. Current research is largely confined to drag reduction in straight pipes, and there are no devices or methods capable of simultaneously evaluating hydraulics, vibration, and noise in actual pump-pipeline systems. More critically, if drag-reducing agents are added without controlling operating conditions, the pump operating point will drift to the high-flow-rate region, causing overload and exacerbating vibration and noise. This "overload drift" problem constitutes a major obstacle to industrial applications, and currently, there is a lack of effective experimental setups and control methods to address it. Summary of the Invention

[0006] This invention addresses the lack of experimental equipment for simultaneously measuring the effects of drag-reducing agents on hydraulics, vibration, and noise in complex pump-pipeline systems, as well as the technical problem of being unable to cope with the deterioration of acoustics and vibration caused by operating point drift after drag-reducing agent injection. It provides a centrifugal pump-assisted drag reduction, noise reduction, and vibration reduction device and its control method, which can simultaneously measure the effects of drag-reducing agents on hydraulics, vibration, and noise in complex pump-pipeline systems, and avoid operating point drift through constant flow assisted control to achieve synergistic effects of drag reduction, noise reduction, and vibration reduction.

[0007] To solve the above-mentioned technical problems, the present invention is achieved through the following technical solution:

[0008] According to one aspect of the present invention, a centrifugal pump-assisted drag reduction, noise reduction, and vibration damping device is provided, comprising a centrifugal pump whose speed is controlled by a frequency converter to achieve flow regulation; the outlet of the centrifugal pump is connected to the first inlet of a static mixer via a first pressure sensor, the outlet of the static mixer is connected to the inlet of a storage tank via a test pipe, the outlet of the storage tank is connected to the inlet of an electromagnetic flowmeter, and the outlet of the electromagnetic flowmeter is connected to the inlet of the centrifugal pump via a second pressure sensor; the storage tank is used to contain a working medium, initially pure water;

[0009] The second inlet of the static mixer is connected to the outlet of the precision metering pump, and the inlet of the precision metering pump is connected to the outlet of the drag-reducing agent storage tank.

[0010] Multiple accelerometers are used to collect the vibration of the centrifugal pump, multiple microphones are used to collect the radiated noise of the centrifugal pump, and a laser tachometer is used to measure the rotational speed of the centrifugal pump.

[0011] The accelerometer and the microphone are both connected to a multi-channel signal analyzer, and the electromagnetic flowmeter, the first pressure sensor, and the second pressure sensor are all connected to a data acquisition unit. The multi-channel signal analyzer, the data acquisition unit, and the laser tachometer are all connected to a computer. The computer controls the speed and flow rate of the centrifugal pump through the frequency converter and the precision metering pump based on the feedback data of speed, vibration, noise, flow rate, and pressure.

[0012] The computer is configured to execute a constant flow coordinated control strategy: after the drag-reducing agent solution is configured through the precision metering pump, the flow signal of the electromagnetic flowmeter is acquired in real time, and based on the deviation between the flow signal and the preset target flow, the output frequency of the frequency converter is adjusted to reduce the speed of the centrifugal pump, so that the flow of the centrifugal pump is restored to the preset target flow.

[0013] Furthermore, a control valve is provided between the first pressure sensor and the first inlet of the static mixer.

[0014] Furthermore, a control valve is provided between the precision metering pump and the second inlet of the static mixer.

[0015] Furthermore, the acceleration sensor comprises at least six sensors, respectively arranged in the axial direction (X) of the pump body volute outlet of the centrifugal pump, the radial direction (Y) of the pump body volute of the centrifugal pump, the radial direction (Z) of the pump body volute of the centrifugal pump, the axial direction (X) of the motor of the centrifugal pump, the radial direction (Z) of the motor of the centrifugal pump, and the base of the centrifugal pump.

[0016] Furthermore, the number of microphones is six, evenly distributed within a 1m radius and 1m height around the pump body of the centrifugal pump; one is located on the axial volute side, one on the axial motor side, two on the volute radial side, and two on the motor radial side.

[0017] Furthermore, the drag-reducing agent stock solution stored in the drag-reducing agent storage tank is an aqueous solution of CTAB / NaSal in a mass ratio of 1:2.

[0018] Furthermore, the preset target flow rate is the stable operating flow rate under pure water baseline conditions.

[0019] According to another aspect of the present invention, a control method based on the above-mentioned centrifugal pump synergistic drag reduction, noise reduction, and vibration damping device is provided, comprising:

[0020] (1) Baseline operating condition setting: The centrifugal pump is run with the initial working medium, adjusted to the preset target flow rate, and after stabilization, the flow rate, vibration and noise data are collected as the baseline;

[0021] (2) Drag reducer injection: The computer injects drag reducer stock solution into the main circuit through the precision metering pump, so that the drag reducer concentration of the working fluid in the main circuit reaches the preset concentration;

[0022] (3) Cooperative control execution: The computer reduces the output frequency of the frequency converter 11 to reduce the speed of the centrifugal pump based on the deviation between the flow value fed back by the electromagnetic flow meter in real time and the preset target flow, until the actual flow is restored to the preset target flow.

[0023] (4) Variable operating condition adjustment: When the preset target flow rate changes or the drag-reducing agent concentration needs to be adjusted, repeat steps (1) to (3).

[0024] The beneficial effects of this invention are:

[0025] (i) This invention achieves significant drag reduction, noise reduction and vibration reduction effects in one fell swoop by using a synergistic strategy of modifying fluid with drag-reducing agent and maintaining constant flow by reducing speed, without changing the pump and pipeline hardware or the original delivery flow rate. It can be directly applied to industrial sites.

[0026] (ii) This invention utilizes the characteristic of drag-reducing agents to reduce system resistance, converting the resistance reduction into a margin for speed reduction; this not only fundamentally avoids the risk of "overload vibration" caused by simply adding drag-reducing agents, but also stabilizes the centrifugal pump's operating point in the high-efficiency and low-noise zone, achieving full-link optimization from fluid performance improvement to power source excitation reduction.

[0027] (III) After verification, using CTAB / NaSal (mass ratio 1:2) drag-reducing agent at a concentration window of 800 ppm and implementing the control method of the present invention, it is possible to achieve excellent synergistic effects such as drag reduction rate >40%, noise energy reduction rate >75%, and vibration reduction rate of key measuring points >75%, providing a cost-effective and easy-to-standardize technical solution for energy-saving and noise-reducing retrofit of industrial pump sets. Attached Figure Description

[0028] Figure 1 This is a schematic diagram of the centrifugal pump collaborative drag reduction, noise reduction and vibration reduction device provided by the present invention.

[0029] Figure 2 for Figure 1 A schematic diagram showing the arrangement of vibration acceleration sensors and microphone measuring points on the pump body and motor of a centrifugal pump.

[0030] Figure 3 This is a graph showing the effect of different concentrations of drag-reducing agents on the total vibration value and vibration reduction rate of each measuring point on the pump body under the rated flow rate in the experimental example. Among them, sub-figure (a) represents the effect of different concentrations of drag-reducing agents on the total vibration value of each measuring point on the pump body, and sub-figure (b) represents the effect of different concentrations of drag-reducing agents on the vibration reduction rate of each measuring point on the pump body.

[0031] Figure 4 This is a graph showing the effect of different concentrations of drag-reducing agents on the sound pressure level and noise reduction at various measuring points around the pump unit under rated flow conditions in the experimental example. Subgraph (a) represents the effect of different concentrations of drag-reducing agents on the sound pressure level at various measuring points around the pump unit, and subgraph (b) represents the effect of different concentrations of drag-reducing agents on the noise reduction at various measuring points around the pump unit.

[0032] Explanation of reference numerals in the attached figures:

[0033] 1: Liquid storage tank; 2: Electromagnetic flow meter; 3-1: First pressure sensor; 3-2: Second pressure sensor; 4: Microphone; 5: Accelerometer; 6: Centrifugal pump; 7: Laser tachometer; 8: Multi-channel signal analyzer; 9: Data acquisition unit; 10: Computer; 11: Frequency converter; 12: Control valve; 13: Drag-reducing agent storage tank; 14: Precision metering pump; 15: Static mixer; 16: Test pipeline; A1-A6: Accelerometer measuring points; M1-M6: Microphone measuring points. Detailed Implementation

[0034] To further understand the invention's content, features, and effects, the following embodiments are provided, along with detailed descriptions in conjunction with the accompanying drawings:

[0035] like Figure 1 As shown, the present invention provides a centrifugal pump collaborative drag reduction, noise reduction and vibration reduction device, including a closed-loop main circuit, a drag-reducing agent injection module, a measurement and sensing unit, and a data acquisition and control module.

[0036] The closed-loop main circuit mainly includes a centrifugal pump 6, a frequency converter 11, a liquid storage tank 1, and a test pipeline 16. The components in the circuit are connected by pipelines.

[0037] Centrifugal pump 6 has its speed controlled by frequency converter 11 to achieve flow regulation. The outlet of centrifugal pump 6 is connected to the inlet of first pressure sensor 3-1. The outlet of first pressure sensor 3-1 is connected to the first inlet A of static mixer 15. The outlet C of static mixer 15 is connected to the inlet of storage tank 1 through test pipe 16. The outlet of storage tank 1 is connected to the inlet of electromagnetic flow meter 2. The outlet of electromagnetic flow meter 2 is connected to the inlet of second pressure sensor 3-2. The outlet of second pressure sensor 3-2 is connected to the inlet of centrifugal pump 6.

[0038] A control valve 12 is installed between the first pressure sensor 3-1 and the first inlet A of the static mixer 15 to adjust the resistance of the pipeline system.

[0039] The drag-reducing agent dosing module includes a drag-reducing agent storage tank 13, a precision metering pump 14, and a static mixer 15. The static mixer 15 is connected in series on the pipeline between the outlet of the first pressure sensor 3-1 and the inlet of the storage tank 1. The second inlet B of the static mixer 15 is connected to the outlet of the precision metering pump 14, and the inlet of the precision metering pump 14 is connected to the outlet of the drag-reducing agent storage tank 13. The precision metering pump 14 injects a high-concentration drag-reducing agent stock solution from the drag-reducing agent storage tank 13 into the static mixer 15 at a set flow rate for uniform mixing, thus entering the closed-loop main circuit. A control valve 12 is installed between the precision metering pump 14 and the second inlet of the static mixer 15 to control the start and stop of mixing.

[0040] The storage tank 1 is used to contain the working medium, which is initially water; after the drag-reducing agent filling module is started, it circulates and stabilizes through the closed-loop main circuit, and then becomes a drag-reducing agent solution made of drag-reducing agent stock solution and water.

[0041] The measurement and sensing unit includes multiple accelerometers 5 for collecting vibrations of the pump body and motor of the centrifugal pump 6, multiple microphones 4 for collecting radiated noise around the centrifugal pump 6, an electromagnetic flowmeter 2 for measuring hydraulic parameters, multiple pressure sensors 3 for measuring the pressure at the inlet and outlet of the centrifugal pump 6 and along the pipeline, and a laser tachometer 7 for measuring the shaft speed of the centrifugal pump 6.

[0042] like Figure 2 As shown, the acceleration sensor 5 includes at least six. The six acceleration sensors 5 are respectively arranged in the pump body volute outlet axial direction X (A1), pump body volute radial direction Y (A2), pump body volute radial direction Z (A3), motor axial direction X (A4), motor radial direction Z (A5), and pump base (A6).

[0043] like Figure 2 As shown, there are six microphones 4, which are evenly distributed around the pump body at a height of 1m and 1m, respectively located on the axial volute side (M1), the axial motor side (M4), the volute radial side (M2 / M6), and the motor radial side (M3 / M5).

[0044] Electromagnetic flowmeter 2 is connected in series in the pipeline between the outlet of the second liquid storage tank 1-2 and the inlet of the centrifugal pump 6.

[0045] The first pressure sensor 3-1 and the second pressure sensor 3-2 are arranged along the inlet and outlet pipes of the centrifugal pump 6.

[0046] The laser tachometer 7 is aligned with the pump shaft of the centrifugal pump 6 to measure the real-time rotational speed of the centrifugal pump 6.

[0047] The data acquisition and control module includes a multi-channel signal analyzer 8, a data acquisition unit 9, and a computer 10. The multi-channel signal analyzer 8 is connected to each of the accelerometers 5 and microphones 4, transmitting the vibration signals measured by the accelerometers 5 and the noise signals measured by the microphones to the multi-channel signal analyzer 8 for processing. The processed information is then further transmitted to the computer 10 for analysis. The data acquisition unit 9 is electrically connected to the electromagnetic flowmeter 2, the first pressure sensor 3-1, and the second pressure sensor 3-2, respectively. It transmits the voltage readings measured by the electromagnetic flowmeter 2 and the pressure sensor 3 to the data acquisition unit 9, converting them into corresponding flow and pressure data. The data acquisition unit 9 then transmits the flow and pressure data to the computer 10. The laser tachometer 7 is directly connected to the computer 10, transmitting the rotational speed data. The computer 10 is also connected to the frequency converter 11 and the precision metering pump 14, used to control the centrifugal pump 6's rotational speed and the precision metering pump 14's flow rate using a constant flow control strategy based on the feedback data of rotational speed, vibration, noise, flow, and pressure, thus achieving closed-loop control.

[0048] Computer 10 is configured to execute a constant flow coordinated control strategy: after the drag-reducing agent solution is prepared by precision metering pump 14, the flow signal of electromagnetic flowmeter 2 is acquired in real time, and based on the deviation between the flow signal and the preset target flow, the output frequency of frequency converter 11 is adjusted to reduce the speed of centrifugal pump 6, so that the flow of centrifugal pump 6 is restored to the preset target flow. Specifically, this may include:

[0049] S1: Preparation of drag-reducing agent solution:

[0050] Taking a common surfactant drag-reducing agent, cetyltrimethylammonium bromide (CTAB), as an example, cetyltrimethylammonium bromide (CTAB) and sodium salicylate (NaSal) are compounded at a mass ratio of 1:2, dissolved in deionized water, and a drag-reducing agent stock solution with a concentration of 4000ppm is prepared and stored in drag-reducing agent storage tank 13.

[0051] S2: Benchmark Test (Pure Water):

[0052] Using deionized water as the working fluid, centrifugal pump 6 is started. By adjusting control valve 12 and frequency converter 11 between the first pressure sensor 3-1 and static mixer 15, the speed of centrifugal pump 6 is stabilized at the rated speed of 2900 r / min, so that the flow rate of centrifugal pump 6 reaches the rated flow rate of 12 m³ / min. 3 / h. After the system has been running stably for 30 seconds, data is continuously collected for 30 seconds (sampling frequency of 51.2 kHz) as a baseline, including: pressure difference between the inlet and outlet of centrifugal pump 6 (calculated head), vibration acceleration time domain and spectrum of each acceleration sensor 5 (A1~A6), sound pressure level and spectrum of each microphone 4 (M1~M6), flow rate, and rotational speed.

[0053] S3: Vibration and noise control:

[0054] S3.1 Injecting drag-reducing agent: The drag-reducing agent stock solution is injected into the closed-loop main circuit through the precision metering pump 14. The amount of stock solution injected is estimated based on the total liquid volume in the closed-loop main circuit, so that the closed-loop main circuit reaches the preset concentration of drag-reducing agent solution, until the concentration of drag-reducing agent solution in the closed-loop main circuit is stable.

[0055] S3.2 Constant speed dosing test (comparative working condition): Keep the current output frequency of inverter 11 unchanged (i.e. the speed is still 2900 r / min), and after the flow rate of the drag reducing agent solution stabilizes, record the new flow rate, head, vibration and noise data.

[0056] S3.3 Constant Flow Co-operation Test: The constant flow control is activated. The computer 10 automatically reduces the output frequency of the frequency converter 11 based on the flow deviation, causing the centrifugal pump 6 to slow down until the flow rate returns to the set value of the pure water reference test (12 m³ / s). 3 ( / h), record the rotational speed, vibration, and noise data at this time.

[0057] S3.4 Variable flow rate repetition: Adjust the frequency converter 11 to change the speed of the centrifugal pump 6 to change the flow rate, repeating S3.1~S3.3.

[0058] S3.5 Variable concentration repetition: The original solution is injected by the precision metering pump 14 to increase the concentration of the main circuit to the next preset concentration. After stabilization, repeat S3.2~S3.4.

[0059] The preset concentrations are 200ppm, 400ppm, 600ppm, 800ppm, and 1000ppm, respectively.

[0060] S4: Data Processing

[0061] All collected data are processed, and the following metrics are defined:

[0062] Vibration reduction rate ;

[0063] In the formula, VAR% represents the vibration reduction rate. The vibration acceleration value is given when the working medium is water, in m / s². 2 ; The vibration acceleration value is given when the working fluid is a drag-reducing agent, in m / s². 2 Vibration data is obtained through accelerometer 5.

[0064] Noise energy reduction rate ;

[0065] in, ;

[0066] In the formula, The sound pressure level reduction is expressed in dB. The sound pressure level is represented in dB when the working medium is water. The sound pressure level is dB when the working fluid is a drag-reducing agent; noise data is obtained through microphone 4.

[0067] Spatial average sound pressure level ;in, This represents the sound pressure level at the i-th microphone measurement point (M1-M6).

[0068] Mean vibration acceleration ; This represents the vibration acceleration at the i-th accelerometer measurement point (A1-A6).

[0069] As can be seen, the control method of the present invention based on the centrifugal pump cooperative drag reduction, noise reduction and vibration reduction device includes:

[0070] (1) Baseline operating condition setting - centrifugal pump 6 is run with the initial working medium, adjusted to the preset target flow rate, and after stabilization, flow rate, vibration and noise data are collected as the baseline;

[0071] (2) Drag reducer injection - Computer 10 injects drag reducer stock solution into the main circuit through precision metering pump 14, so that the drag reducer concentration of the working fluid in the main circuit reaches the preset concentration.

[0072] (3) Cooperative control execution - The computer 10 automatically reduces the output frequency of the frequency converter 11 to reduce the speed of the centrifugal pump 6 based on the deviation between the flow value fed back by the electromagnetic flow meter 2 in real time and the preset target flow, until the actual flow is restored to the preset target flow.

[0073] (4) Variable operating condition adjustment - When the preset target flow rate changes or the drag-reducing agent concentration needs to be adjusted, repeat steps (1) to (3).

[0074] The preset target flow rate is the stable operating flow rate under pure water baseline conditions, and all coordinated control after the addition of drag-reducing agents aims to restore this flow rate.

[0075] The following experimental examples further illustrate the content and effects of the centrifugal pump synergistic drag reduction, noise reduction, and vibration reduction experimental device and method provided by this invention:

[0076] Implementation conditions:

[0077] Centrifugal pump: Model IHW32-160GA, rated flow rate 12 m³ / h 3 / h, rated head 20 m, rated speed 2900 r / min, number of impeller blades Z=6;

[0078] Drag reducer: CTAB / NaSal, mass ratio 1:2, prepared as a 4000ppm stock solution;

[0079] Working medium: deionized water, temperature 25±1℃;

[0080] Test pipeline: DN32 stainless steel pipe, 20 m in total length, including 4 90° elbows and 4 valves.

[0081] Operating procedures:

[0082] (I) System preparation and pure water baseline test

[0083] Close the control valve 12 at the outlet of centrifugal pump 6 to approximately 30% of its full open position. Start centrifugal pump 6, adjust the frequency converter 11 to achieve a speed of 2900 r / min, and adjust the control valve 12 to stabilize the flow rate at 12 m³ / min. 3 / h. After 30 seconds of stable operation, data was continuously collected for 10 seconds at a sampling frequency of 51.2 kHz: the reading from electromagnetic flowmeter 2 was 12.0 m. 3 / h, pressure sensor 3 measured the pump inlet and outlet pressure difference to be 20.1 m (head), if Figure 3 As shown, the average vibration acceleration at each measuring point of sensor 5 was measured to be 0.264 m / s². 2 The spatial average sound pressure level measured at each measuring point in microphone 4 was 71.5 dB.

[0084] Adjust the frequency converter 11 sequentially to change the flow rate from 2.3 m³ / s.3 / h gradually increased to 12 m 3 / h, record the data under each stable operating condition, and plot the pure water acoustic vibration reference curve.

[0085] (II) Drag-reducing agent addition and concentration stabilization

[0086] Start the precision metering pump 14 to inject 4000 ppm CTAB / NaSal stock solution from the drag reducer tank 13 into the static mixer 15 at the calculated flow rate, so that the main circuit reaches the target concentration of 800 ppm. Monitor the change in the conductivity of the main circuit with a conductivity meter. When the deviation of three consecutive measurements (1 minute apart) is less than 5%, the concentration is determined to be stable, and the metering pump is stopped.

[0087] (III) Comparison of constant-rate dosing conditions

[0088] Keeping the inverter output frequency constant (speed still 2900 r / min), and waiting for the system to stabilize, read the data: the flow rate increased to 14.2 m³ / min. 3 / h (18% over rated), the head increased to 21.5 m, and the average vibration acceleration at each measuring point of the accelerometer sensor 5 increased to 0.45 m / s². 2 (Increase of 70.5%), the spatial average sound pressure level at each measuring point in microphone 4 increased to 75.1 dB (an increase of 3.6 dB). This operating condition was used to demonstrate that simply adding a drag reducer without adjusting the speed would lead to overload and deterioration of acoustic vibration.

[0089] (iv) Constant current coordinated control condition

[0090] The constant current control program is started, and computer 10 reads the current value of electromagnetic flowmeter 2 as 14.2 m³. 3 / h, compared to the target value of 12 m 3 The deviation was +18.3% per hour. The inverter output frequency was gradually reduced, and the flow rate was monitored in real time. After approximately 45 seconds, the flow rate stabilized at 12.0 m³ / h. 3 At this point, the rotational speed dropped to 2295 r / min. After 30 seconds of stable operation, data was collected: the average vibration acceleration at each measuring point of the accelerometer sensor 5 decreased to 0.060 m / s². 2 (relative to pure water standard 0.264 m / s) 2 The reduction rate (VAR%) was 77.3%, and the spatial average sound pressure level at each measuring point in microphone 4 was 65.3 dB (a decrease of 6.2 dB, NER%). Meanwhile, spectral analysis showed that the leaf frequency shifted from 290 Hz to 229.5 Hz, with an amplitude reduction of 60.4%; the broadband energy above 500 Hz generally decreased by more than 70%.

[0091] (V) Data Processing and Result Analysis Following the method described in Section S4, calculate the vibration reduction rate (VAR%) and noise energy reduction rate (NER%) for each operating condition, and plot the results. Figure 3 , Figure 4 .

[0093] (vi) Variable concentration test

[0094] Tests were conducted at concentrations of 200, 400, 600, 800, and 1000 ppm, and the results are as follows: Figure 3 , Figure 4 As shown. Figure 3 The study demonstrated the vibration acceleration and vibration reduction of solutions with different concentrations at different measuring points. There were significant differences in the vibration reduction and noise reduction effects at different concentrations and measuring points. For vibration, the vibration reduction effect was more significant at measuring points A1, A2, and A3 of the vibration acceleration sensor 5 located on the pump volute side. For all measuring points, the consistent result was a significant vibration reduction effect under the condition of 600~1000ppm drag-reducing agent solution. Figure 4 The study demonstrates the noise pressure level and noise reduction performance of solutions with different concentrations at different measuring points. For different microphones and 5 measuring points, the noise reduction performance varies slightly at different measuring points, but all show significant noise reduction effects under drag-reducing agent solution conditions of 600~1000ppm. CTAB / NaSal (mass ratio 1:2) achieves the best synergistic effect in the concentration range of 600~1000ppm. Specifically, at 800ppm, the drag reduction rate (DR%) is 42.2%, the vibration reduction rate (VAR%) is 77.3%, and the noise energy reduction rate (NER%) is 79.1%.

[0095] Although the preferred embodiments of the present invention have been described above in conjunction with the accompanying drawings, the present invention is not limited to the specific embodiments described above. The specific embodiments described above are merely illustrative and not restrictive. Those skilled in the art can make many specific modifications under the guidance of the present invention without departing from the spirit and scope of the claims, and these modifications all fall within the scope of protection of the present invention.

Claims

1. A centrifugal pump-assisted drag reduction, noise reduction, and vibration damping device, comprising a centrifugal pump, wherein the centrifugal pump's speed is controlled by a frequency converter to achieve flow regulation; characterized in that, The outlet of the centrifugal pump is connected to the first inlet of the static mixer via a first pressure sensor. The outlet of the static mixer is connected to the inlet of the storage tank via a test pipe. The outlet of the storage tank is connected to the inlet of the electromagnetic flow meter. The outlet of the electromagnetic flow meter is connected to the inlet of the centrifugal pump via a second pressure sensor. The storage tank is used to contain the working medium, initially pure water. The second inlet of the static mixer is connected to the outlet of the precision metering pump, and the inlet of the precision metering pump is connected to the outlet of the drag-reducing agent storage tank. Multiple accelerometers are used to collect the vibration of the centrifugal pump, multiple microphones are used to collect the radiated noise of the centrifugal pump, and a laser tachometer is used to measure the rotational speed of the centrifugal pump. The accelerometer and the microphone are both connected to a multi-channel signal analyzer, and the electromagnetic flowmeter, the first pressure sensor, and the second pressure sensor are all connected to a data acquisition unit. The multi-channel signal analyzer, the data acquisition unit, and the laser tachometer are all connected to a computer. The computer controls the speed and flow rate of the centrifugal pump through the frequency converter and the precision metering pump based on the feedback data of speed, vibration, noise, flow rate, and pressure. The computer is configured to execute a constant flow coordinated control strategy: after the drag-reducing agent solution is configured through the precision metering pump, the flow signal of the electromagnetic flowmeter is acquired in real time, and based on the deviation between the flow signal and the preset target flow, the output frequency of the frequency converter is adjusted to reduce the speed of the centrifugal pump, so that the flow of the centrifugal pump is restored to the preset target flow.

2. The centrifugal pump synergistic drag reduction, noise reduction, and vibration damping device according to claim 1, characterized in that, A control valve is provided between the first pressure sensor and the first inlet of the static mixer.

3. The centrifugal pump synergistic drag reduction, noise reduction, and vibration damping device according to claim 1, characterized in that, A control valve is provided between the precision metering pump and the second inlet of the static mixer.

4. The centrifugal pump synergistic drag reduction, noise reduction, and vibration damping device according to claim 1, characterized in that, The acceleration sensors include at least six, which are respectively arranged in the axial direction (X) of the pump body volute outlet of the centrifugal pump, the radial direction (Y) of the pump body volute of the centrifugal pump, the radial direction (Z) of the pump body volute of the centrifugal pump, the axial direction (X) of the motor of the centrifugal pump, the radial direction (Z) of the motor of the centrifugal pump, and the base of the centrifugal pump.

5. The centrifugal pump synergistic drag reduction, noise reduction, and vibration damping device according to claim 1, characterized in that, The number of microphones is six, evenly distributed within a 1m radius and 1m height around the pump body of the centrifugal pump; one is located on the axial volute side, one on the axial motor side, two on the volute radial side, and two on the motor radial side.

6. The centrifugal pump synergistic drag reduction, noise reduction, and vibration damping device according to claim 1, characterized in that, The drag-reducing agent stock solution stored in the drag-reducing agent storage tank is an aqueous solution of CTAB / NaSal in a mass ratio of 1:

2.

7. The centrifugal pump synergistic drag reduction, noise reduction, and vibration damping device according to claim 1, characterized in that, The preset target flow rate is the stable operating flow rate under pure water baseline conditions.

8. A control method for a centrifugal pump synergistic drag reduction, noise reduction, and vibration damping device according to any one of claims 1-7, characterized in that, include: (1) Baseline operating condition setting: The centrifugal pump is run with the initial working medium, adjusted to the preset target flow rate, and after stabilization, the flow rate, vibration and noise data are collected as the baseline; (2) Drag reducer injection: The computer injects drag reducer stock solution into the main circuit through the precision metering pump, so that the drag reducer concentration of the working fluid in the main circuit reaches the preset concentration; (3) Cooperative control execution: The computer reduces the output frequency of the frequency converter 11 to reduce the speed of the centrifugal pump based on the deviation between the flow value fed back by the electromagnetic flow meter in real time and the preset target flow, until the actual flow is restored to the preset target flow. (4) Variable operating condition adjustment: When the preset target flow rate changes or the drag-reducing agent concentration needs to be adjusted, repeat steps (1) to (3).

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