Method and system for testing atomization characteristics of attemperation water nozzle

Abstract

The invention relates to a method and a system for testing atomization characteristics of a desuperheating water nozzle, and belongs to the technical field of thermodynamic system energy conservation. The system comprises a water circulation unit, an atomization test unit, a data acquisition unit and a data processing and control unit, and by integrating a laser particle analyzer, a high-speed camera, a flow meter and a pressure sensor, synchronous and accurate monitoring of atomization particle size, form, flow and pressure is achieved. The test method comprises the steps of nozzle working state simulation, characteristic parameter acquisition, data analysis and performance evaluation, and establishment of a grading evaluation system. The method solves the problems of dependence on manual observation and low quantification precision in the prior art, improves the test efficiency and repeatability, provides reliable data support for design optimization and performance diagnosis of the desuperheating water nozzle, and is suitable for desuperheater nozzle tests in the fields of thermal power, chemical engineering and the like.

Description

TECHNICAL FIELD

[0001] The present application relates to a kind of test methods and systems of atomization characteristics of desuperheating water nozzle, belong to the energy-saving technology field of thermal system. BACKGROUND

[0002] Desuperheating water nozzle is an important component of steam desuperheating device, mainly applied in thermal power generating unit and industrial steam system, desuperheating water is sprayed and atomized through nozzle, mixed with high-temperature steam, to achieve the purpose of accurate temperature control. Atomization quality, such as water droplet size, distribution uniformity, coverage, etc., directly affects the efficiency of desuperheating and the safety of system, and poor atomization can even cause pipe wall thermal stress cracking or steam water. Therefore, the atomization performance of desuperheating water nozzle is a very key data in design and selection, which usually needs to be obtained through test.

[0003] At present, the evaluation of atomization uniformity by traditional test method depends on subjective visual observation, lacks real-time monitoring means, has low quantitative precision, and at the same time, the test process needs to rely on manual operation and record, which is low in efficiency and poor in repeatability. SUMMARY

[0004] The present application aims to solve the problems of traditional test method, such as lack of real-time monitoring means, low quantitative precision, and test process needs to rely on manual operation and record, which is low in efficiency and poor in repeatability, and proposes a kind of test method and system of atomization characteristics of desuperheating water nozzle.

[0005] The technical scheme of the present application:

[0006] A kind of test system of atomization characteristics of desuperheating water nozzle, comprising:

[0007] Water circulation unit: including water tank, booster pump, regulating valve, filter and circulating water pump, for providing and recycling test water;

[0008] Atomization test unit: including test cabin, nozzle assembly and air compressor, the test cabin is provided with observation window and drain, for carrying out nozzle atomization test;

[0009] Data acquisition unit: including laser particle size analyzer, high-speed camera, flowmeter, pressure sensor and data acquisition card, for real-time acquisition of atomization particle size, atomization form, flow and pressure data;

[0010] Data processing and control unit: including PLC controller and computer, for controlling test parameters, recording data and analyzing nozzle atomization characteristics;

[0011] The water tank is connected with the booster pump and the nozzle assembly in sequence through the water outlet pipeline, the water outlet pipeline is provided with the adjusting valve, the flow meter and the pressure sensor in sequence according to the water flow direction, the nozzle assembly is arranged in the test cabin, the drain outlet of the test cabin is connected with the filter, the circulating water pump and the water tank in sequence through the backwater pipeline; the nozzle assembly is connected with the air compressor arranged outside the test cabin, the sidewall of the test cabin is provided with the observation window, and the laser particle size instrument and the high-speed camera are arranged in the test cabin; the data transmission ends of the laser particle size instrument, the high-speed camera, the flow meter and the pressure sensor are connected with the data acquisition card, the output end of the data acquisition card is connected with the PLC controller, and the PLC controller is connected with the booster pump, the adjusting valve and the computer.

[0012] Specifically, the range of the laser particle size instrument is 1-500 μm, and the precision is ±1 μm; the shooting speed of the high-speed camera is greater than 100,000 fps, the spatial resolution is 0.1 mm / pixel, and the angle error is less than or equal to 0.5°; the range of the flow meter is 3-500 m³ / h, and the precision is ±0.5%.

[0013] A test method for the atomization characteristics of a desuperheating water nozzle, the test method is realized by means of the test system for the atomization characteristics of the desuperheating water nozzle, and comprises the following steps:

[0014] S1: nozzle assembly working state simulation: install the nozzle assembly and set the working condition parameters, start the nozzle assembly to spray desuperheating water, and wait for the state to be stable;

[0015] S2: characteristic parameter acquisition: measure the droplet particle size and distribution by means of the laser particle size instrument, shoot the atomization form by means of the high-speed camera, and monitor the flow and pressure by means of the flow meter and the pressure sensor;

[0016] S3: data analysis: transmit the collected data to the computer, calculate the average particle size, the atomization cone angle and the uniformity index;

[0017] S4: performance evaluation: generate the nozzle atomization characteristic report according to the grading evaluation system.

[0018] Specifically, the working condition parameters in step S1 include the desuperheating water pressure, the compressed air pressure and the flow, which are used for simulating the actual working environment of the nozzle.

[0019] Specifically, the judgment standard of the grading evaluation system in step S4 is:

[0020] A: the average particle size is less than 80 μm, the atomization cone angle is greater than 70°, and the uniformity coefficient is greater than 0.85;

[0021] B: the average particle size is less than 120 μm, the atomization cone angle is greater than 60°, and the uniformity coefficient is greater than 0.75;

[0022] C: the nozzle assembly does not reach the A or B standard.

[0023] Advantages of the present application:

[0024] 1. Multi-parameter dynamic testing technology: The parameters of the test system are accurately adjusted by the PLC controller, and the atomization data are synchronously obtained, so that the data deviation between the laboratory and the field is solved;

[0025] 2. Establishment of atomization characteristic grading evaluation system: The comprehensive performance of the nozzle is analyzed through the comprehensive evaluation index of atomization characteristics, such as: average particle size < 80 μm, atomization cone angle > 70°, uniformity coefficient > 0.85 for A grade; average particle size < 120 μm, atomization cone angle > 60°, uniformity coefficient > 0.75 for B grade; and the rest for C grade;

[0026] 3. High data reliability: The test data are stored in real time, and historical data query and report production are supported, so that the error of manual recording is avoided. BRIEF DESCRIPTION OF DRAWINGS

[0027] Figure 1 is a test method flowchart of the present application;

[0028] Figure 2 is a system schematic diagram of the present application.

[0029] In the figure, 1 is a water tank, 2 is a booster pump, 3 is an adjusting valve, 4 is a flowmeter, 5 is a pressure sensor, 6 is a filter, 7 is a circulating water pump, 8 is an air compressor, 9 is a nozzle assembly, 10 is a test cabin, 11 is a laser particle size analyzer, 12 is a high-speed camera, 13 is a data acquisition card, 14 is a PLC controller, 15 is a computer, 16 is an observation window, and 17 is a drain. DETAILED DESCRIPTION

[0030] The present application will be further described in detail below with reference to the accompanying drawings, and the following examples are an explanation of the present application, and the present application is not limited to the following examples.

[0031] Example 1: As shown, the desuperheating water nozzle atomization test system mainly includes a water circulation unit, an atomization test unit, a data acquisition unit, and a data processing and control unit. Figure 2

[0032] 1. Water circulation unit

[0033] The water circulation unit includes a water tank 1, a booster pump 2, an adjusting valve 3, a filter 6, and a circulating water pump 7. The water tank 1 is used for storing filtered test water; the booster pump 2 provides stable water supply pressure for the nozzle; the adjusting valve 3 is used for accurately adjusting the water supply pressure; the filter 6 is used for removing impurities in the circulating water; and the circulating water pump 7 recycles the test water to the water tank 1, realizing the recycling of water.

[0034] 2. Atomization test unit​

[0035] The atomization test unit includes a test cabin 10, a nozzle assembly 9, and an air compressor 8. The test cabin 10 is a closed space, and has a detachable nozzle mounting seat inside for fixing different types of desuperheating water nozzles; an observation window 16 facilitates real-time observation of the atomization state; and a drain 17 is used to drain the test water. The air compressor 8 provides compressed air for the nozzle to assist atomization.

[0036] 3. Data acquisition unit

[0037] The data acquisition unit includes a laser particle size analyzer 11, a high-speed camera 12, a flow meter 4, a pressure sensor 5, and a data acquisition card 13. The laser particle size analyzer 11 is used to measure the droplet size distribution (range 1-500 μm, accuracy ±1 μm); the high-speed camera 12 is used to take pictures of the atomization form (shooting speed >100,000 fps, resolution 0.1 mm / pixel); the flow meter 4 and the pressure sensor 5 are used to monitor the water flow (range 3-500 m³ / h, accuracy ±0.5%) and pressure, respectively; and the data acquisition card 13 transmits data to a computer 15 in real time through a PLC controller 14.

[0038] 4. Data processing and control unit

[0039] The data processing and control unit includes the PLC controller 14 and the computer 15. The PLC controller 14 is used to automatically adjust test parameters (such as pressure and flow); the computer 15 analyzes data through professional software, calculates atomization characteristic indexes (such as average particle size, atomization cone angle, and uniformity index), and generates a performance report.

[0040] Example 2: As shown in Figure 1 , Figure 2 a test method for the atomization characteristics of a desuperheating water nozzle, which is implemented by using the test system for the atomization characteristics of a desuperheating water nozzle described in Example 1, and specifically includes the following steps:

[0041] 1. Test preparation: Add clean desuperheating water to the water tank; then install and fix the nozzle to be tested on the nozzle assembly 9 in the test cabin 10; connect the water supply pipeline and check the sealing of the pipeline; start the PLC controller 14 and enter the main interface.

[0042] 2. Set test conditions: Set parameters on the PLC controller 14, input desuperheating water pressure, flow, and test time, etc., then save the parameters and return to the main interface.

[0043] 3. Start the test: Start the test, the PLC controller 14 controls the booster pump 2 to start, the opening of the regulating valve 3 is gradually increased, the test condition is observed through the observation window 16, and the real-time parameters on the display screen of the PLC controller 14 are monitored at the same time, until the parameters are stable.

[0044] 4. Nozzle characteristic parameter acquisition and recording: start the laser particle size analyzer 11 to measure the droplet size; start the high-speed camera 12 to begin shooting the video of the jet atomization; the flow meter 4 measures the nozzle flow, and the test data is monitored through the display screen of the PLC controller 14; synchronously transmit each parameter to the data acquisition card 13, and transmit to the computer 15 through the PLC controller 14 and record.

[0045] 5. End the test: after the test is completed, the PLC controller 14 controls the booster pump 2 to stop and the regulating valve 3 to close; open the drain 17 of the atomization test cabin 10 to drain the accumulated water, filter through the filter 6, and recycle the water to the water tank 1 through the circulating water pump 7 for the next test.

[0046] 6. Analyze the atomization performance of the nozzle and write an evaluation report: analyze and arrange each data on the computer 15 through professional software, calculate the core indexes such as the average particle size and uniformity index of the nozzle atomization, and write a nozzle performance evaluation report.

[0047] Example 3: Test of a desuperheating water nozzle of a steam turbine bypass device:

[0048] Working condition setting: desuperheating water pressure 0.8 MPa; compressed air pressure 1.2 MPa, flow rate 5 Nm 3 / h (used for simulating auxiliary atomization steam);

[0049] Acquisition process: use the laser particle size analyzer 13 to measure the droplet size and particle size distribution (pulse interval 1 μs); use the high-speed camera 12 to shoot the spray video; read the flow meter 4 reading (8.85 m 3 / h);

[0050] Characteristic analysis: use software analysis to obtain the average particle size D32=65.3 μm; the spray cone angle is 78.2°; the atomization uniformity is 0.89;

[0051] Evaluation conclusion: the nozzle performance rating is A level, and it is recommended to be used for corresponding desuperheater upgrade.

[0052] The above examples are only exemplary descriptions of the present application and do not limit the protection scope thereof, and a person skilled in the art can also make changes to parts thereof, as long as the spirit and substance of the present application are not exceeded, and it is within the protection scope of the present application.

Claims

1. A test system for the atomization characteristics of a cooling water nozzle, characterized in that: include: Water circulation unit: comprising a water tank (1), a booster pump (2), a regulating valve (3), a filter (6) and a circulating water pump (7), for providing and recovering test water; Atomization test unit: comprising a test chamber (10), a nozzle assembly (9) and an air compressor (8), wherein the test chamber (10) is provided with an observation window (16) and a drain port (17) for conducting a nozzle atomization test; Data acquisition unit: including a laser particle size analyzer (11), a high-speed camera (12), a flow meter (4), a pressure sensor (5) and a data acquisition card (13), for real-time acquisition of atomized particle size, atomization morphology, flow rate and pressure data; Data processing and control unit: including a PLC controller (14) and a computer (15), used to control test parameters, record data and analyze nozzle atomization characteristics; The water tank (1) is connected to the booster pump (2) and the nozzle assembly (9) in sequence through a water outlet pipe. The water outlet pipe is installed with a regulating valve (3), a flow meter (4), and a pressure sensor (5) in sequence according to the water flow direction. The nozzle assembly (9) is placed in the test cabin (10). The drain outlet (17) of the test cabin (10) is connected to the filter (6), the circulating water pump (7), and the water tank (1) in sequence through a return water pipe. The nozzle assembly (9) is connected to the air compressor (8) placed outside the test cabin (10). An observation window (16) is provided on the side wall of the test cabin (10). A laser particle size analyzer (11) and a high-speed camera (12) are provided in the test cabin (10). The data transmission ends of the laser particle size analyzer (11), the high-speed camera (12), the flow meter (4), and the pressure sensor (5) are all connected to a data acquisition card (13). The output end of the data acquisition card (13) is connected to a PLC controller (14). The PLC controller (14) is connected to the booster pump (2), the regulating valve (3), and the computer (15).

2. The test system for the atomization characteristics of the cooling water nozzle according to claim 1 is characterized in that: The laser particle size analyzer (11) has a measuring range of 1 to 500 μm and an accuracy of ±1 μm; the high-speed camera (12) has a shooting speed greater than 100,000 fps, a spatial resolution of 0.1 mm / pixel, and an angular error of ≤0.5°; the flow meter (4) has a measuring range of 3 to 500 m³ / h and an accuracy of ±0.5%.

3. A method for testing the atomization characteristics of a cooling water nozzle, the method being implemented by the testing system for the atomization characteristics of a cooling water nozzle according to claim 1 or 2, characterized in that: The following steps are involved: S1: Simulation of the working state of the nozzle assembly (9): Install the nozzle assembly (9) and set the working parameters, start the nozzle assembly (9) to spray cooling water, and wait for the state to stabilize; S2: Characteristic parameter collection: The droplet size and distribution are measured by a laser particle size analyzer (11), the atomization morphology is photographed by a high-speed camera (12), and the flow rate and pressure are monitored by a flow meter (4) and a pressure sensor (5); S3: Data analysis: The collected data are transferred to a computer (15) to calculate the average particle size, atomization cone angle, and uniformity index; S4: Performance evaluation: Generate a nozzle atomization characteristics report based on the grading evaluation system.

4. The test method for the atomization characteristics of a cooling water nozzle according to claim 4, characterized in that: The working condition parameters in step S1 include the desuperheating water pressure, the compressed air pressure and the flow rate, which are used to simulate the actual working environment of the nozzle.

5. The test method for the atomization characteristics of a cooling water nozzle according to claim 4, characterized in that: The criteria for the grading evaluation system in step S4 are: Grade A: average particle size <80μm, atomization cone angle >70°, uniformity coefficient >0.85; Class B: average particle size <120μm, atomization cone angle >60°, uniformity coefficient >0.75; Class C: Nozzle assemblies that do not meet Class A or Class B standards (9).

Images