阅读说明：本技术 一种用于叶片水流量测试设备的在线校准方法 (Online calibration method for blade water flow testing equipment ) 是由 段小俊 张作慧 刘猛 白雪峰 于莉 于 2021-09-15 设计创作，主要内容包括：本发明涉及一种用于叶片水流量测试设备的在线校准方法,采用分参数校准方式进行校准试验,并结合测量不确定度评定的综合评价方式从而实现在线校准,分别是步骤一：试验条件参数校准：试验条件参数包括水流量的压力和温度；步骤二：控制系统的现场校准；步骤三：数据采集系统校准；步骤四：流量参数校准；步骤五：通过以上四个步骤的分部分校准,对各个部分的校准结果进行测量不确定度评定。本发明取代传统计量器具单独溯源并配合标准样件试验的方式进行校准,规避了在用的标准样件的量值均出自测试设备本身和校准过程只考核了测试设备的重复性和稳定性指标的缺点,对叶片水流量测试设备进行了有效的溯源。(The invention relates to an on-line calibration method for blade water flow testing equipment, which adopts a sub-parameter calibration mode to carry out a calibration test and combines a comprehensive evaluation mode of measurement uncertainty evaluation to realize on-line calibration, and comprises the following steps: test condition parameter calibration: the test condition parameters comprise pressure and temperature of water flow; step two: field calibration of the control system; step three: calibrating a data acquisition system; step four: calibrating flow parameters; step five: through the calibration of the parts in the four steps, the measurement uncertainty evaluation is carried out on the calibration result of each part. The method replaces a mode of independently tracing the source of a conventional quantity device and matching with a standard sample test for calibration, overcomes the defects that the quantity values of the standard sample used are all from the testing equipment and the repeatability and stability indexes of the testing equipment are only checked in the calibration process, and effectively traces the source of the blade water flow testing equipment.)

1. An online calibration method for blade water flow test equipment is characterized by specifically comprising the following steps:

the method comprises the following steps: test condition parameter calibration: the test condition parameters comprise pressure and temperature of water flow;

step two: field calibration of the control system;

step three: calibrating a data acquisition system;

step four: calibrating flow parameters;

step five: through the calibration of the parts in the four steps, the measurement uncertainty evaluation is carried out on the calibration result of each part.

2. The on-line calibration method for the blade water flow rate test equipment according to claim 1, wherein: the test condition parameter calibration device for performing test condition parameter calibration in the first step comprises a standard digital pressure gauge, a platinum resistance thermometer and an adjusting valve which are connected in series in the blade water flow testing equipment, wherein the platinum resistance thermometer, the standard digital pressure gauge and the adjusting valve are sequentially connected in series behind a pressure transmitter and in a main pipeline in front of a G1 valve and a G3 valve, and are close to the position of a water inlet of a blade tool; the standard digital pressure gauge is connected with the main pipeline through a tee joint, and the platinum resistance thermometer is also embedded into the main pipeline through the tee joint.

3. The on-line calibration method for the blade water flow rate test equipment according to claim 2, wherein: the specific method for calibrating the test condition parameters comprises the following steps: when the test condition parameters are calibrated, the high-pressure turbine blade water flow testing equipment is operated, the regulating valve in the test condition parameter calibration device is regulated, so that the indicating values of the platinum resistance thermometer and the standard digital pressure gauge meet the technical requirements, and finally, the standard digital pressure gauge and the platinum resistance thermometer are used as the measuring standards of pressure and temperature, and the pressure gauge and the thermometer measuring values of the high-pressure turbine blade water flow testing equipment are recorded.

4. The on-line calibration method for the blade water flow rate test equipment according to claim 1, wherein: the control system of the blade water flow testing equipment in the second step mainly comprises a control unit, a time relay and an electromagnetic valve, wherein the time relay is calibrated by adopting a stopwatch, the electromagnetic valve is calibrated on site by adopting an oscilloscope to test the response time of the electromagnetic valve, an input wiring port of the oscilloscope is connected in parallel to a control signal input port of the electromagnetic valve, the high-pressure blade water flow testing equipment runs, the time relay and the stopwatch are started simultaneously, when the time relay reaches a set value, the stopwatch is stopped, and the time recorded as the standard time of the time relay; after the electromagnetic valve acts, the oscilloscope records the response curve of the electromagnetic valve, and the opening and closing time of the electromagnetic valve is obtained by measuring the rising time and the falling time of the response curve.

5. The on-line calibration method for the blade water flow rate test equipment according to claim 1, wherein: the specific method for calibrating the data acquisition system in the third step is as follows: the multifunctional standard signal source and the pulse signal source are connected with the calibration adapter through cables, the calibration adapter is connected with the data acquisition module of the high-pressure turbine blade water flow testing equipment through cables, the pressure transmitter, the temperature transmitter and the flow sensor of the high-pressure turbine blade water flow testing equipment are respectively disconnected with the corresponding control circuits of the data acquisition system, then the multifunctional standard signal source and the pulse signal source are respectively accessed into the corresponding control circuits of the data acquisition system as the measurement standard, regulating multifunctional standard signal source and pulse signal source, simulating pressure transmitter, temperature transmitter and flow sensor to input standard electric signals, switching pressure, temperature and flow signals via calibration adapter, and respectively reading measured values on the pressure gauge, the thermometer and the flowmeter after passing through the data acquisition module.

6. The on-line calibration method for the blade water flow rate test equipment according to claim 1, wherein: when the flow parameter is calibrated in the fourth step, a mass flowmeter is used as a metering standard flowmeter and is connected in series with a main pipeline behind the test condition parameter calibration device in the first step and in front of a G1 valve and a G3 valve, and the position of the main pipeline is close to the water inlet of the blade tool; when the calibrated blade water flow test equipment runs, water flow firstly flows through the mass flow meter, then passes through the pipeline and then flows through the high-pressure turbine blade to be tested, the difference between the measurement result of the blade water flow test equipment and the measurement result of the mass flow meter is compared, and the flow parameter of the high-pressure turbine blade water flow test equipment is calibrated.

7. The on-line calibration method for the blade water flow rate test equipment according to claim 6, wherein: the mass flow meter should ensure an accuracy level of 0.1 order within its range.

Technical Field

The invention belongs to the technical field of metering test, and particularly relates to an online calibration method for blade water flow test equipment.

Background

The blade water flow testing equipment is used as special testing equipment for testing the water flow of the blades, is widely applied to testing in the assembly manufacturing industry of gas turbines, aircraft engines, steamships and the like, and is important equipment for testing the water flow of the blades. At present, the related research of special test equipment starts late, and the specificity of the test equipment is strong, so that the calibration difficulty is high. At present, the method mainly adopts the mode that a measuring instrument singly traces the source and is matched with a standard sample test for calibration, but the magnitude of the used standard sample is from the testing equipment, the calibration process only examines the repeatability and stability index of the testing equipment, only meets the requirement of management standard, the accuracy of data cannot be judged, and effective tracing is not carried out in strict meaning.

Disclosure of Invention

Aiming at the defects in the prior art, the invention provides an online calibration method for the blade water flow testing equipment, which replaces the traditional meter with a mode of independent source tracing and standard sample test matching for calibration through a method of sub-parameter calibration and comprehensive evaluation, overcomes the defect that the repeatability and stability indexes of the testing equipment are only checked in the measurement value of the used standard sample and the calibration process, and effectively traces the source of the blade water flow testing equipment.

An online calibration method for blade water flow testing equipment specifically comprises the following steps:

the method comprises the following steps: test condition parameter calibration: the test condition parameters comprise pressure and temperature of water flow;

step two: field calibration of the control system;

step three: calibrating a data acquisition system;

step four: calibrating flow parameters;

step five: through the calibration of the parts in the four steps, the measurement uncertainty evaluation is carried out on the calibration result of each part.

The test condition parameter calibration device for performing test condition parameter calibration in the first step comprises a standard digital pressure gauge, a platinum resistance thermometer and an adjusting valve which are connected in series in the blade water flow testing equipment, wherein the platinum resistance thermometer, the standard digital pressure gauge and the adjusting valve are sequentially connected in series behind a pressure transmitter and in a main pipeline in front of a G1 valve and a G3 valve, and are close to the position of a water inlet of a blade tool; the standard digital pressure gauge is connected with the main pipeline through a tee joint, and the platinum resistance thermometer is also embedded into the main pipeline through the tee joint.

The specific method for calibrating the test condition parameters comprises the following steps: when the test condition parameters are calibrated, the high-pressure turbine blade water flow testing equipment is operated, the regulating valve in the test condition parameter calibration device is regulated, so that the indicating values of the platinum resistance thermometer and the standard digital pressure gauge meet the technical requirements, and finally, the standard digital pressure gauge and the platinum resistance thermometer are used as the measuring standards of pressure and temperature, and the pressure gauge and the thermometer measuring values of the high-pressure turbine blade water flow testing equipment are recorded.

The control system of the blade water flow testing equipment in the second step mainly comprises a control unit, a time relay and an electromagnetic valve, wherein the time relay is calibrated by adopting a stopwatch, the electromagnetic valve is calibrated on site by adopting an oscilloscope to test the response time of the electromagnetic valve, an input wiring port of the oscilloscope is connected in parallel to a control signal input port of the electromagnetic valve, the high-pressure blade water flow testing equipment runs, the time relay and the stopwatch are started simultaneously, when the time relay reaches a set value, the stopwatch is stopped, and the time recorded as the standard time of the time relay; after the electromagnetic valve acts, the oscilloscope records the response curve of the electromagnetic valve, and the opening and closing time of the electromagnetic valve is obtained by measuring the rising time and the falling time of the response curve.

The specific method for calibrating the data acquisition system in the third step is as follows: the multifunctional standard signal source and the pulse signal source are connected with the calibration adapter through cables, the calibration adapter is connected with the data acquisition module of the high-pressure turbine blade water flow testing equipment through cables, the pressure transmitter, the temperature transmitter and the flow sensor of the high-pressure turbine blade water flow testing equipment are respectively disconnected with the corresponding control circuits of the data acquisition system, then the multifunctional standard signal source and the pulse signal source are respectively accessed into the corresponding control circuits of the data acquisition system as the measurement standard, regulating multifunctional standard signal source and pulse signal source, simulating pressure transmitter, temperature transmitter and flow sensor to input standard electric signals, switching pressure, temperature and flow signals via calibration adapter, and respectively reading measured values on the pressure gauge, the thermometer and the flowmeter after passing through the data acquisition module.

When the flow parameter is calibrated in the fourth step, a mass flowmeter is used as a metering standard flowmeter and is connected in series with a main pipeline behind the test condition parameter calibration device in the first step and in front of a G1 valve and a G3 valve, and the position of the main pipeline is close to the water inlet of the blade tool; when the calibrated blade water flow test equipment runs, water flow firstly flows through the mass flow meter, then passes through the pipeline and then flows through the high-pressure turbine blade to be tested, the difference between the measurement result of the blade water flow test equipment and the measurement result of the mass flow meter is compared, and the flow parameter of the high-pressure turbine blade water flow test equipment is calibrated.

The mass flow meter should ensure an accuracy level of 0.1 order within its range.

The invention has the beneficial effects that: the calibration device is arranged, the mode that a conventional quantity device is singly traced and matched with a standard sample test is replaced for calibration, the defects that the quantity values of the standard samples are all obtained from the testing equipment, and only the repeatability and stability indexes of the testing equipment are checked in the calibration process are overcome, systematic and effective tracing is carried out on the blade water flow testing equipment, and the calibration problem of the blade water flow testing equipment is solved.

Drawings

FIG. 1 is a schematic view of the working principle of a water flow rate testing device for blades;

FIG. 2 is a schematic view of a device for calibrating parameters of test conditions according to the present invention;

FIG. 3 is a schematic diagram showing the connection of a standard digital pressure gauge in the test condition parameter calibration device according to the present invention;

FIG. 4 is a calibration schematic of the calibration step of the data acquisition system of the present invention;

FIG. 5 is a schematic diagram of the connections of a mass flow meter during calibration of flow parameters in the present invention;

wherein the content of the first and second substances,

1-platinum resistance thermometer, 2-standard digital pressure gauge, 3-regulating valve and 4-mass flowmeter.

Detailed Description

For better understanding of the present invention, the technical solutions and effects of the present invention will be described in detail by the following embodiments with reference to the accompanying drawings.

An online calibration method for blade water flow testing equipment specifically comprises the following steps:

the working principle of the blade water flow testing equipment is shown in figure 1, when the water flow test is carried out, the water flow test equipment firstly provides the tested part, namely the high-pressure turbine blade, with pressure and temperature test conditions meeting the process requirements, after the fluid in the pipeline is stable, the test time is controlled through a time relay and an electromagnetic valve, the collection is carried out, and the water flow passing through the high-vortex blade in fixed time is measured through a flowmeter and a data acquisition system. According to the working principle of the high-pressure turbine blade water flow testing equipment, the flow test result measured by the testing equipment is directly related to the test pressure, the test temperature, the test time and the flowmeter for collecting water flow, so that a sub-parameter calibration mode is adopted for calibration test during calibration, and a comprehensive evaluation mode of measurement uncertainty evaluation is combined to realize online calibration.

The method comprises the following steps: test condition parameter calibration

The test condition parameters included pressure and temperature of the water flow.

The pressure parameter is a key parameter in the flow test, the pipeline, the position and the height of the flow test equipment for measuring the pressure parameter have large influence, and the selection of the pressure sampling point position is the premise of ensuring the accuracy of the pressure measurement in the calibration of the test condition parameter. The calibration device for the test pressure can ensure that the pressure production position of the pressure calibration device is close to the fluid inlet position of a part to be tested (a high-pressure turbine blade), and the influence of height difference and flow channel change on the measurement result is avoided as much as possible. The connection of the calibration device and the water flow testing equipment of the calibrated blade has the core problems that the design and manufacture of the connection device with the minimum influence on the flow environment are needed, and the universality of the device is ensured.

As shown in fig. 2, the test condition parameter calibration device for performing the test condition parameter calibration in the first step includes a standard digital pressure gauge 2, a platinum resistance thermometer 1 and a regulating valve 3 connected in series in the vane water flow rate test equipment, wherein the platinum resistance thermometer 1, the standard digital pressure gauge 2 and the regulating valve 3 are sequentially connected in series in a main pipeline behind the pressure transmitter and in front of the G1 valve and the G3 valve, and are close to the water inlet position of the vane tool. As shown in fig. 3, the standard digital pressure gauge 2 is connected to the main pipe by a tee joint, and the platinum resistance thermometer 1 is also inserted into the main pipe by a tee joint. The test condition parameter calibration device has the functions of pressure measurement and temperature measurement, and adopts a standard digital pressure gauge 2 and a platinum resistance thermometer 1 as the measurement standards of pressure and temperature.

The test pressure of the high-pressure turbine blade water flow test equipment is measured by a pressure transmitter in the test equipment, the test temperature is measured by a temperature transmitter of a thermometer, and the test pressure is calculated by a data acquisition system and displayed by a pressure meter and the thermometer. When the test condition parameters are calibrated, the high-pressure turbine blade water flow testing equipment is operated, the regulating valve 3 in the test condition parameter calibration device is regulated, the indicating values of the platinum resistance thermometer 1 and the standard digital pressure gauge 2 meet the technical requirements, finally, the standard digital pressure gauge 2 and the platinum resistance thermometer 1 are used as the measuring standards of pressure and temperature, the measuring values of the pressure gauge and the temperature gauge of the high-pressure turbine blade water flow testing equipment are recorded, and the difference between the measuring values and the measuring standard values of the standard digital pressure gauge 2 and the platinum resistance thermometer 1 is the indicating value error of the calibration result. The test condition parameter calibration device calibrates the pressure and temperature parameters of the whole system, and avoids the adverse effects on the high-pressure turbine blade water flow test equipment caused by respectively and independently calibrating the pressure transmitter, the temperature transmitter, the pressure gauge and the thermometer.

Step two: in-situ calibration of control system

The control system of the blade water flow testing equipment mainly comprises a control unit, a time relay and an electromagnetic valve, wherein the time relay is used for timing, and the electromagnetic valve is controlled to be switched on and off through the control unit. The control system mainly ensures the accuracy of the test by controlling the test time, and the factor influencing the flow test result is the response time of the time relay and the electromagnetic valve. The calibration of the time relay is carried out by adopting a stopwatch, the field calibration of the electromagnetic valve is carried out by adopting an oscilloscope to test the response time of the electromagnetic valve, an input wiring port of the oscilloscope is connected in parallel with a control signal input port of the electromagnetic valve, the high-pressure turbine blade water flow test equipment runs, the time relay and the stopwatch are started simultaneously, when the time relay reaches a set value, the stopwatch is stopped, and the time recorded by the stopwatch is the standard time of the time relay. After the electromagnetic valve acts, the oscilloscope records the response curve of the electromagnetic valve, and the opening and closing time of the electromagnetic valve is obtained by measuring the rising time and the falling time of the response curve.

Step three: data acquisition system calibration

Connecting a multifunctional standard signal source and a pulse signal source with a calibration adapter through cables, connecting the calibration adapter with a data acquisition module of high-pressure turbine blade water flow testing equipment through cables, as shown in figure 4, combining JJF1048-1995 data acquisition system calibration standard, disconnecting a pressure transmitter, a temperature transmitter and a flow sensor of the high-pressure turbine blade water flow testing equipment from corresponding control lines of a data acquisition system respectively, then connecting the multifunctional standard signal source and the pulse signal source as metering standards into corresponding control lines of the data acquisition system respectively, adjusting the multifunctional standard signal source and the pulse signal source, simulating the input of standard electric signals of the pressure transmitter, the temperature transmitter and the flow sensor, switching the pressure, the temperature and the flow signals through the calibration adapter, and respectively switching the pressure, the temperature and the flow signals through the data acquisition module on a pressure gauge, a pulse signal source and a flow sensor, And reading the measured value on the thermometer and the flowmeter, wherein the difference between the measured value and the multifunctional standard signal source and the pulse signal source is the indicating value error of the calibration result.

Step four: flow parameter calibration

According to the characteristics of the high-pressure turbine blade water flow testing equipment, the mass flowmeter 4 is used as a metering standard flowmeter during flow parameter calibration, the mass flowmeter 4 is connected in series in a main pipeline after the test condition parameter calibration device in the step one and before the G1 valve and the G3 valve, and the water inlet position of the blade tool is close to that of the main pipeline, namely the test condition parameter calibration device and the mass flowmeter 4 are connected in series in sequence. The mass flow meter 4 should ensure a 0.1 level accuracy level within its range, and it has no special requirements for the medium, the straight pipe section and the installation position. The mass flow meter 4 is used as a metering standard flow meter, and the working state of the blade water flow testing equipment is not influenced in the calibration process. As shown in fig. 5, the connection between the standard flowmeter and the blade water flow rate test device is realized by setting an extension pipeline at the interface between the blade water flow rate test device and the measured high-pressure turbine blade, and connecting the mass flowmeter 4 into the extension pipeline. When the calibrated blade water flow test equipment runs, water flow firstly flows through the mass flow meter 4 and then passes through the pipeline, then flows through the high-pressure turbine blade to be tested, the difference between the measurement result of the blade water flow test equipment and the measurement result of the mass flow meter 4 is compared, and the flow parameter of the high-pressure turbine blade water flow test equipment is calibrated.

Step five: assessment of measurement uncertainty

And through the part calibration of the four steps, the measurement uncertainty of the calibration result of each part is evaluated to obtain the standard uncertainty of each part, and the standard uncertainty is synthesized to obtain the integral expansion uncertainty of the engine flow testing equipment.