Flow instrument test-free air flow calibration method for VGT axial nozzle ring supercharger

Abstract

The invention discloses a flow instrument test-free air flow calibration method for a VGT axial nozzle ring supercharger, and particularly relates to the technical field of turbochargers, which comprises the following steps: preparing equipment, calculating required air flow requirements, obtaining a performance curve relation graph according to analog simulation analysis, forming a theoretical performance curve relation graph by analog calculation values, and calibrating the performance curve relation graph according to the theoretical performance curve relation graph. The method comprises the steps of gas source connection, displacement gauge installation and positioning, initial measurement of automatic program detection, test out-of-tolerance fine adjustment and repeated measurement of automatic program detection. According to the invention, the matching relation among the actuator control pressure, the actuator valve rod displacement, the VGT axial nozzle ring blade opening degree and the rocker arm rocker rotation angle is simulated and calculated, and the pneumatic test bench and the displacement sensor are utilized at the same time; the actual matching condition of the actuator valve rod displacement, the VGT axial nozzle ring blade opening degree and the rocker arm rocker rotation angle of a VGT structure supercharger product in the production process can be monitored on line, the air flow calibration technology free of flow instrument testing is achieved, and the design requirement is met.

Description

Technical Field

[0001] The present invention relates to the technical field of turbochargers, and more particularly to an air flow calibration method for a VGT axial nozzle ring supercharger without flowmeter testing. Background Art

[0002] Currently, in the aftermarket, the production of VGT axial nozzle ring turbochargers generally fails to control the air flow performance parameters of the nozzle ring, nor does it carry out special assembly calibration process development, resulting in poor consistency in the assembly quality of the finished product and failure to meet the usage requirements of aftermarket customers.

[0003] Conventional small-displacement VNT turbochargers correspond to rotating blade nozzle rings, and their air flow calibration requires the use of flow testers and special fixtures. The large-displacement VGT turbochargers corresponding to this project correspond to axial blade nozzle rings. The engine displacement they match is generally 6.7L-12.7L, and the application scenario is pickup truck models. The turbocharger is large in size and weight, and the air flow value required for calibration is also large. The conventional flow tester range cannot meet the air flow test conditions of this type of turbocharger; if conventional flow testers are continued to be used for air flow calibration, the flow tester and tooling fixtures that match the large-displacement turbocharger must be redesigned, and because this type of turbocharger is heavy and large in size, a corresponding material transfer fixture must also be designed.

[0004] At the same time, for the air flow calibration of this large-displacement VGT axial nozzle ring turbocharger, due to the lack of a flow table of suitable specifications, the air flow value after test assembly is not monitored, and the movement of the internal nozzle ring is controlled only by the actuator control pressure and the valve stem displacement, and the performance relationship among the actuator control pressure, the actuator valve stem displacement and the VGT axial nozzle ring blade opening is not matched. Therefore, in order to online monitor the actual coordination of the actuator valve stem displacement, the VGT axial nozzle ring blade opening and the rocker arm rocker rotation angle of the VGT structure supercharger products during the production process, and realize the air flow calibration process without flow meter testing, an air flow calibration method without flow meter testing of VGT axial nozzle ring supercharger is proposed. Summary of the invention

[0005] In order to overcome the above defects of the prior art, the present invention provides an air flow calibration method of a VGT axial nozzle ring supercharger without flowmeter testing, so as to solve the problems raised in the above background technology.

[0006] To achieve the above object, the present invention provides the following technical solution: an air flow calibration method for a VGT axial nozzle ring supercharger without flowmeter testing, specifically comprising the following steps: Step 1: Equipment preparation and calculation of required air flow requirements, prepare pneumatic test bench E1, displacement sensor E2 and displacement sensor E3 for standby, identify the matching relationship between actuator control pressure, actuator valve stem displacement, VGT axial nozzle ring blade opening and rocker arm rocker rotation angle, and perform accurate calculation; Step 2: Obtain a performance curve relationship diagram based on simulation analysis, obtain the positions of the two mechanical dead points of the VGT nozzle ring motion system after actual assembly based on simulation analysis, identify the matching relationship between the rocker arm rocker rotation angle, actuator valve stem displacement and VGT axial nozzle ring blade opening at the two mechanical dead point positions, and simultaneously obtain a performance curve relationship diagram of the actuator control pressure, actuator valve stem displacement, rocker arm rocker rotation angle and VGT axial nozzle ring blade opening within the two mechanical dead point ranges based on simulation analysis; Step 3: The simulation calculation value forms a theoretical performance curve relationship diagram. The performance relationship curve diagram uses the actuator control pressure as the active driving variable. According to the actual working conditions of the supercharger on the vehicle, the mechanical structure variable position is matched with this pressure change. When the actuator control pressure changes, the corresponding actuator valve stem displacement, rocker arm rocker rotation angle and VGT axial nozzle ring blade opening are simulated and calculated synchronously. The above four simulated calculation values ​​form a theoretical pressure, angle, displacement and opening performance curve relationship diagram; Step 4: Connect the air source and install the displacement gauge. Connect the rubber air pipe of the pneumatic test bench E1 to the air nozzle of the actuator, and return the air source pressure of the pneumatic test bench E1 to zero. Position the probe of the displacement sensor E2 in contact with the valve stem end of the actuator, and return the displacement display value of the displacement sensor E2 to zero. Position the probe of the displacement sensor E3 in contact with the top of the blade of the VGT axial nozzle ring, and return the displacement display value of the displacement sensor E3 to zero. Step 5: Initial test of automatic program detection. After calling out the pre-programmed automatic test program in the pneumatic test bench E1 device, start the program to run automatically and conduct the test. The pneumatic test bench E1 is used to check the matching relationship between the actuator control pressure, actuator valve stem displacement, and VGT axial nozzle ring blade opening corresponding to each pressure point. After the pneumatic test bench E1 device automatically pressurizes the actuator to the pressure of the key detection point, the displacement sensor E2 feeds back the actuator valve stem displacement in real time, and the displacement sensor E3 feeds back the blade opening displacement of the VGT axial nozzle ring in real time. When all the four key detection points are detected, the program of the pneumatic test bench E1 device automatically identifies and determines whether the actuator valve stem displacement and the VGT axial nozzle ring blade opening under the pressure of the four key detection points are qualified. If qualified, proceed to the next step. Step 6: Test the out-of-tolerance fine-tuning. During the test, if the measured VGT axial nozzle ring opening value exceeds the standard opening displacement range, the actuator is fine-tuned so that the fine-tuned actuator pushes the blade opening of the VGT axial nozzle ring to the standard opening displacement range under the same pressure, so as to ensure that the blade opening of the "VGT axial nozzle ring" under various pressures can correspond to the respective correct air flow positions; Step 7: Retest the automatic detection of the program. After fine-tuning, re-enter step 5 and use the automatic test program for detection. When the re-test result passes, the product's VGT air flow position calibration is qualified; otherwise, repeat the previous step until it passes.

[0007] Preferably, the pneumatic test bench E1 in step one is used to provide actuator control pressure, automatically pressurize to the key detection point pressure, and automatically identify and determine whether the actuator valve stem displacement and the VGT axial nozzle ring blade opening are qualified. The displacement sensor E2 in step one is used to measure the valve stem displacement of the actuator, contact and position the probe of E2 with the valve stem end of the actuator, and reset the displacement display value to zero.

[0008] Preferably, in the step one, the accurate calculation is performed to make the VGT axial nozzle ring blade opening meet the air flow requirement required for the actual working condition and match it with the actual working condition. In the step one, the displacement sensor E3 is used to measure the blade opening displacement of the VGT axial nozzle ring, the probe of E3 is contacted and positioned with the top of the blade, and the displacement display value is reset to zero.

[0009] Preferably, the positions of the two mechanical stop points in step 2 are the FOHS blade fully open mechanical stop point and the FCHS blade fully closed mechanical stop point.

[0010] Preferably, the opening of the VGT axial nozzle ring blade in step three determines the actual air flow rate at the volute end of the turbocharger. The larger the opening, the more air passes through and the greater the flow rate, and vice versa.

[0011] Preferably, in step 4, a sealing test of the connection parts is added to ensure that no air leakage occurs during the test process to affect the test results.

[0012] Preferably, when testing in step five, the pneumatic test bench E1 equipment uses the pressure value as the active driving quantity to check the pressure at each pressure point. In step five, since there is no suitable angle detector to monitor the rotation angle of the rocker arm in real time during the actual test, and the relationship between the rotation angle of the rocker arm and the actuator control pressure, the actuator valve stem displacement and the VGT axial nozzle ring blade opening has been matched during the design simulation calculation, the rotation angle of the rocker arm and the rocker arm is not monitored during the actual test.

[0013] Preferably, the test positions in the automatic test program in step 5 are 4 key detection points extracted from the performance curve defined in the design stage, and the corresponding pressure points are: 1600mbar, 1800mbar, 2000mbar, and 2200mbar.

[0014] Preferably, the fine adjustment of the actuator position in step six is ​​performed by increasing or decreasing the pre-compression of the spring inside the actuator. In step six, the blade opening of the VGT axial nozzle ring is pushed to the standard opening displacement range to ensure that the blade opening of the VGT axial nozzle ring at various pressures can correspond to the respective correct air flow positions.

[0015] Preferably, in step six, the amplitude of the test tolerance fine adjustment is limited to prevent excessive adjustment from causing damage to the actuator and the VGT axial nozzle ring.

[0016] Technical effects and advantages of the present invention: 1. Through simulation analysis, the matching relationship between the actuator control pressure, actuator valve stem displacement, VGT axial nozzle ring blade opening and rocker arm rocker rotation angle is accurately identified, providing a scientific and accurate theoretical basis for actual production, ensuring that the design of the supercharger is highly matched with the actual working conditions. By using the existing pneumatic test bench E1 and displacement sensors E2 and E3, the air flow calibration process without flow meter testing is realized, breaking the limitation of traditional reliance on specific flow testers, reducing equipment costs and test complexity, and eliminating the need to upgrade the flow bench, reducing equipment investment and redesign of tooling fixtures, and improving production efficiency. At the same time, the automatic test program can quickly and accurately detect key parameters, saving test time; 2. By combining simulation calculation with actual testing, it is ensured that the blade opening of the VGT axial nozzle ring meets the air flow requirements required by actual working conditions. During the test, real-time feedback on the actuator stem displacement and blade opening displacement, as well as automatic recognition and judgment by the program, ensure the accuracy and reliability of the test results. When the test is out of tolerance, the blade opening can be adjusted to the standard range by fine-tuning the actuator position. This fine-tuning method is achieved by increasing or decreasing the pre-compression of the spring inside the actuator. It is simple and flexible to operate, and can effectively solve quality problems in actual production. It limits the amplitude of fine-tuning of test out-of-tolerance to prevent damage to the actuator and VGT axial nozzle ring due to excessive adjustment, thereby improving the safety and stability of the equipment; 3. In summary, through the mutual influence of the above-mentioned multiple effects, an air flow calibration method for a VGT axial nozzle ring supercharger without flow meter test has many significant beneficial effects. In terms of technological innovation, the multi-parameter matching relationship is accurately determined through simulation, and the innovative process uses existing equipment to achieve flow meter-free test calibration, reducing costs and complexity; in practical applications, it is efficient and convenient, and there is no need to upgrade the flow table to save time and investment; it is accurate and reliable, combining simulation calculation with actual detection to ensure accurate results; it can flexibly adjust the out-of-tolerance situation, is simple to operate and ensures equipment safety; adding sealing detection improves test accuracy and reliability, and provides a powerful and practical solution for the production and quality control of large-displacement VGT axial nozzle ring turbochargers. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 It is a schematic diagram of the method flow structure of the present invention.

[0018] Figure 2 The graph is a relationship graph of the actuator control pressure, actuator valve stem displacement, rocker arm rocker rotation angle and VGT axial nozzle ring blade opening in the embodiment of the present invention. Structural diagram. DETAILED DESCRIPTION

[0019] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0020] Example: An air flow calibration method for a VGT axial nozzle ring supercharger without flowmeter testing specifically comprises the following steps: Step 1: Equipment preparation and calculation of required air flow requirements, prepare pneumatic test bench E1, displacement sensor E2 and displacement sensor E3 for standby, identify the matching relationship between actuator control pressure, actuator valve stem displacement, VGT axial nozzle ring blade opening and rocker arm rocker rotation angle, and perform accurate calculation; In the step 1, the pneumatic test bench E1 is used to provide the actuator control pressure, and automatically pressurizes the pressure to the key detection point, and automatically identifies and determines whether the actuator valve stem displacement and the VGT axial nozzle ring blade opening are qualified. In the step 1, the displacement sensor E2 is used to measure the actuator valve stem displacement, contact and position the probe of E2 with the valve stem end of the actuator, and reset the displacement display value to zero; In the step 1, the displacement sensor E3 is used to measure the displacement of the blade opening of the VGT axial nozzle ring, and the probe of E3 is contacted and positioned with the top of the blade, and the displacement display value is reset to zero; Step 2: Obtain a performance curve relationship diagram based on simulation analysis, obtain the positions of the two mechanical dead points of the VGT nozzle ring motion system after actual assembly based on simulation analysis, identify the matching relationship between the rocker arm rocker rotation angle, actuator valve stem displacement and VGT axial nozzle ring blade opening at the two mechanical dead point positions, and simultaneously obtain a performance curve relationship diagram of the actuator control pressure, actuator valve stem displacement, rocker arm rocker rotation angle and VGT axial nozzle ring blade opening within the two mechanical dead point ranges based on simulation analysis; The positions of the two mechanical stop points in step 2 are the FOHS blade fully open mechanical stop point and the FCHS blade fully closed mechanical stop point; Step 3: The simulation calculation value forms a theoretical performance curve relationship diagram. The performance relationship curve diagram uses the actuator control pressure as the active driving variable. According to the actual working conditions of the supercharger on the vehicle, the mechanical structure variable position is matched with this pressure change. When the actuator control pressure changes, the corresponding actuator valve stem displacement, rocker arm rocker rotation angle and VGT axial nozzle ring blade opening are simulated and calculated synchronously. The above four simulated calculation values ​​form a theoretical pressure, angle, displacement and opening performance curve relationship diagram; The opening of the VGT axial nozzle ring blade in step 3 determines the actual air flow rate at the volute end of the turbocharger. The larger the opening, the more air passes through, and the greater the flow rate, and vice versa. Step 4: Connect the air source and install the displacement gauge. Connect the rubber air pipe of the pneumatic test bench E1 to the air nozzle of the actuator, and return the air source pressure of the pneumatic test bench E1 to zero. Position the probe of the displacement sensor E2 in contact with the valve stem end of the actuator, and return the displacement display value of the displacement sensor E2 to zero. Position the probe of the displacement sensor E3 in contact with the top of the blade of the VGT axial nozzle ring, and return the displacement display value of the displacement sensor E3 to zero. In step 4, a sealing test of the connection part is added to ensure that there is no leakage during the test that affects the test results; Step 5: Initial test of automatic program detection. After calling out the pre-programmed automatic test program in the pneumatic test bench E1 device, start the program to run automatically and conduct the test. The pneumatic test bench E1 is used to check the matching relationship between the actuator control pressure, actuator valve stem displacement, and VGT axial nozzle ring blade opening corresponding to each pressure point. After the pneumatic test bench E1 device automatically pressurizes the actuator to the pressure of the key detection point, the displacement sensor E2 feeds back the actuator valve stem displacement in real time, and the displacement sensor E3 feeds back the blade opening displacement of the VGT axial nozzle ring in real time. When all the four key detection points are detected, the program of the pneumatic test bench E1 device automatically identifies and determines whether the actuator valve stem displacement and the VGT axial nozzle ring blade opening under the pressure of the four key detection points are qualified. If qualified, proceed to the next step. When testing in step 5, the pneumatic test bench E1 device uses the pressure value as the active driving quantity to check the pressure at each pressure point. In step 5, there is no suitable angle detector for real-time monitoring of the rocker arm rotation angle during actual testing, and the rocker arm rotation angle has been matched with the actuator control pressure, the actuator valve stem displacement and the VGT axial nozzle ring blade opening during the design simulation calculation. The rocker arm rotation angle is not monitored during actual testing. The test position in the automatic test program in step 5 is 4 key detection points extracted from the performance curve defined in the design stage, and the corresponding pressure points are: 1600mbar, 1800mbar, 2000mbar, and 2200mbar respectively; Step 6: Test the out-of-tolerance fine-tuning. During the test, if the measured VGT axial nozzle ring opening value exceeds the standard opening displacement range, the actuator is fine-tuned so that the fine-tuned actuator pushes the blade opening of the VGT axial nozzle ring to the standard opening displacement range under the same pressure, so as to ensure that the blade opening of the "VGT axial nozzle ring" under various pressures can correspond to the respective correct air flow positions; The fine adjustment of the actuator position in step 6 is performed by increasing or decreasing the pre-compression amount of the spring inside the actuator. In step 6, the blade opening of the VGT axial nozzle ring is pushed to the standard opening displacement range to ensure that the blade opening of the VGT axial nozzle ring under various pressures can correspond to the respective correct air flow positions. In step 6, the amplitude of the test out-of-tolerance fine adjustment is limited to prevent damage to the actuator and the VGT axial nozzle ring caused by excessive adjustment; Step 7: Retest the automatic detection of the program. After fine-tuning, re-enter step 5 and use the automatic test program for detection. When the re-test result passes, the product's VGT air flow position calibration is qualified; otherwise, repeat the previous step until it passes.

[0021] Finally, it should be noted that the drawings of the embodiments disclosed in the present invention only involve structures related to the embodiments disclosed in the present invention, and other structures can refer to common designs. In the absence of conflicts, the same embodiment and different embodiments of the present invention can be combined with each other; Finally: The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A method for calibrating air flow rate of a VGT axial nozzle ring supercharger without flow meter test, characterized in that: The specific steps include: Step 1: Equipment preparation and calculation of required air flow requirements, prepare pneumatic test bench E1, displacement sensor E2 and displacement sensor E3 for standby, identify the matching relationship between actuator control pressure, actuator valve stem displacement, VGT axial nozzle ring blade opening and rocker arm rocker rotation angle, and perform accurate calculation; Step 2: Obtain a performance curve relationship diagram based on simulation analysis, obtain the positions of the two mechanical dead points of the VGT nozzle ring motion system after actual assembly based on simulation analysis, identify the matching relationship between the rocker arm rocker rotation angle, actuator valve stem displacement and VGT axial nozzle ring blade opening at the two mechanical dead point positions, and simultaneously obtain a performance curve relationship diagram of the actuator control pressure, actuator valve stem displacement, rocker arm rocker rotation angle and VGT axial nozzle ring blade opening within the two mechanical dead point ranges based on simulation analysis; Step 3: The simulation calculation value forms a theoretical performance curve relationship diagram. The performance relationship curve diagram uses the actuator control pressure as the active driving variable. According to the actual working conditions of the supercharger on the vehicle, the mechanical structure variable position is matched with this pressure change. When the actuator control pressure changes, the corresponding actuator valve stem displacement, rocker arm rocker rotation angle and VGT axial nozzle ring blade opening are simulated and calculated synchronously. The above four simulated calculation values ​​form a theoretical pressure, angle, displacement and opening performance curve relationship diagram; Step 4: Connect the air source and install the displacement gauge. Connect the rubber air pipe of the pneumatic test bench E1 to the air nozzle of the actuator, and return the air source pressure of the pneumatic test bench E1 to zero. Position the probe of the displacement sensor E2 in contact with the valve stem end of the actuator, and return the displacement display value of the displacement sensor E2 to zero. Position the probe of the displacement sensor E3 in contact with the top of the blade of the VGT axial nozzle ring, and return the displacement display value of the displacement sensor E3 to zero. Step 5: Initial test of automatic program detection. After calling out the pre-programmed automatic test program in the pneumatic test bench E1 device, start the program to run automatically and conduct the test. The pneumatic test bench E1 is used to check the matching relationship between the actuator control pressure, actuator valve stem displacement, and VGT axial nozzle ring blade opening corresponding to each pressure point. After the pneumatic test bench E1 device automatically pressurizes the actuator to the pressure of the key detection point, the displacement sensor E2 feeds back the actuator valve stem displacement in real time, and the displacement sensor E3 feeds back the blade opening displacement of the VGT axial nozzle ring in real time. When all the four key detection points are detected, the program of the pneumatic test bench E1 device automatically identifies and determines whether the actuator valve stem displacement and the VGT axial nozzle ring blade opening under the pressure of the four key detection points are qualified. If qualified, proceed to the next step. Step 6: Test the out-of-tolerance fine-tuning. During the test, if the measured VGT axial nozzle ring opening value exceeds the standard opening displacement range, the actuator will be fine-tuned so that the fine-tuned actuator can push the blade opening of the VGT axial nozzle ring to the standard opening displacement range under the same pressure, so as to ensure that the blade opening of the "VGT axial nozzle ring" under various pressures can correspond to the correct air flow position. Step 7: Retest the automatic detection of the program. After fine-tuning, re-enter step 5 and use the automatic test program for detection. When the re-test result passes, the product's VGT air flow position calibration is qualified; otherwise, repeat the previous step until it passes.

2. The air flow calibration method of the VGT axial nozzle ring supercharger without flowmeter test according to claim 1, characterized in that: In the step 1, the pneumatic test bench E1 is used to provide the actuator control pressure, and automatically pressurize it to the key detection point pressure, and automatically identify and determine whether the actuator valve stem displacement and the VGT axial nozzle ring blade opening are qualified. In the step 1, the displacement sensor E2 is used to measure the valve stem displacement of the actuator, contact and position the probe of E2 with the valve stem end of the actuator, and reset the displacement display value to zero.

3. The air flow calibration method of the VGT axial nozzle ring supercharger without flowmeter test according to claim 1, characterized in that: In the step one, the displacement sensor E3 is used to measure the displacement of the blade opening of the VGT axial nozzle ring, and the probe of E3 is contacted and positioned with the top of the blade, and the displacement display value is reset to zero.

4. The air flow calibration method of the VGT axial nozzle ring supercharger without flow meter test according to claim 1, characterized in that: The positions of the two mechanical stop points in step 2 are the FOHS blade fully open mechanical stop point and the FCHS blade fully closed mechanical stop point.

5. The air flow calibration method of the VGT axial nozzle ring supercharger without flowmeter test according to claim 1, characterized in that: The opening of the VGT axial nozzle ring blade in step three determines the actual air flow rate at the volute end of the turbocharger. The larger the opening, the more air passes through and the greater the flow rate, and vice versa.

6. The air flow calibration method of the VGT axial nozzle ring supercharger without flow meter test according to claim 1, characterized in that: In step 4, a sealing test of the connection parts is added to ensure that no air leakage occurs during the test and affects the test results.

7. The air flow calibration method of the VGT axial nozzle ring supercharger without flow meter test according to claim 1, characterized in that: When testing in step five, the pneumatic test bench E1 equipment uses pressure value as the active driving quantity to check the pressure at each pressure point. In step five, there is no suitable angle detector for real-time monitoring of the rocker arm rotation angle during actual testing, and the rocker arm rotation angle has been matched with the actuator control pressure, the actuator valve stem displacement and the VGT axial nozzle ring blade opening during the design simulation calculation. The rocker arm rotation angle is not monitored during actual testing.

8. The air flow calibration method of the VGT axial nozzle ring supercharger without flow meter test according to claim 1, characterized in that: The test positions in the automatic test program in step 5 are 4 key detection points extracted from the performance curve defined in the design stage, and the corresponding pressure points are: 1600mbar, 1800mbar, 2000mbar, and 2200mbar.

9. The air flow calibration method of the VGT axial nozzle ring supercharger without flowmeter test according to claim 1, characterized in that: The fine adjustment of the actuator position in step six is ​​carried out by increasing or decreasing the pre-compression of the spring inside the actuator. In step six, the blade opening of the VGT axial nozzle ring is pushed to the standard opening displacement range to ensure that the blade opening of the VGT axial nozzle ring at various pressures can correspond to the respective correct air flow positions.

10. The air flow calibration method of the VGT axial nozzle ring supercharger without flow meter test according to claim 1, characterized in that: In step six, the amplitude of the test tolerance fine adjustment is limited to prevent excessive adjustment from causing damage to the actuator and the VGT axial nozzle ring.

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