CN111487872A - Multichannel coordination control method for large-volume airplane airtight strength test - Google Patents

Multichannel coordination control method for large-volume airplane airtight strength test Download PDF

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CN111487872A
CN111487872A CN202010454578.XA CN202010454578A CN111487872A CN 111487872 A CN111487872 A CN 111487872A CN 202010454578 A CN202010454578 A CN 202010454578A CN 111487872 A CN111487872 A CN 111487872A
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inflation
time
air
airtight
deflation
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燕晨耀
吝继锋
周季冰
李宏亮
高利娃
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AVIC Aircraft Strength Research Institute
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    • G05B—CONTROL OR REGULATING SYSTEMS IN GENERAL; FUNCTIONAL ELEMENTS OF SUCH SYSTEMS; MONITORING OR TESTING ARRANGEMENTS FOR SUCH SYSTEMS OR ELEMENTS
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Abstract

The embodiment of the invention discloses a multichannel coordinated control method for a large-volume airplane airtight strength test, which comprises the following steps: determining the gas flow state of the inflation/deflation valve according to the inflation/deflation working principle of the inflation platform and the inflation/deflation process of the airtight cabin; establishing a time mathematical model of the air-tight chamber inflation/deflation according to the determined gas flow state, and calculating the inflation time and the deflation time of the air-tight chamber, wherein the time mathematical model of the air-tight chamber inflation/deflation comprises a time mathematical model of the air-tight chamber inflation and a time mathematical model of the air-tight chamber deflation; determining the type and the number of the inflating tables and the time setting of the load spectrum according to the inflating time and the deflating time of the airtight cabin; and establishing a virtual control loop, and performing multi-channel coordination control on the airtight test strength test. The embodiment of the invention discloses a multi-channel coordination control method based on inflation/deflation time calculation, which improves the test efficiency and the control precision.

Description

Multichannel coordination control method for large-volume airplane airtight strength test
Technical Field
The application relates to the technical field of but not limited to airtight strength tests of large-volume airplane cabin structures, in particular to a multichannel coordinated control method for the airtight strength tests of large-volume airplanes.
Background
In the airtight strength test of the large-volume airplane, the size of the airplane is large, so the time required for inflation/deflation of the airtight strength test is long, the air flow distribution in the airtight cabin is uneven in the process of simultaneously inflating a plurality of inflation tables, and the test control precision is difficult to guarantee.
At present, the selection of the type and the number of the inflating tables required in the large-volume airplane airtight strength test and the time setting of the load spectrum in the test control system are mainly based on experience, and are not theoretically verified.
The invention establishes a mathematical model of the air inflation/deflation time of the air tightness strength test of the large-volume airplane structure by researching the air inflation/deflation working principle of the air inflation platform and the air inflation/deflation process of the air tight cabin, provides a control method based on the calculation of the air inflation/deflation time, gives a virtual control loop, and realizes the multi-channel coordination control of the air tightness strength test of the large-volume airplane, thereby improving the test efficiency and the control precision.
Disclosure of Invention
In order to solve the technical problem, the embodiment of the invention provides a multichannel coordination control method for an airtight strength test of a large-volume airplane, and provides a multichannel coordination control method based on charging/discharging time calculation in the airtight strength test of a large-volume airplane structure, so that the test efficiency and the control precision are improved.
The embodiment of the invention provides a multichannel coordinated control method for a large-volume airplane airtight strength test, which comprises the following steps:
determining the gas flow state of the inflation/deflation valve according to the inflation/deflation working principle of the inflation platform and the inflation/deflation process of the airtight cabin;
establishing a time mathematical model of the air-tight chamber inflation/deflation according to the determined gas flow state, and calculating the inflation time and the deflation time of the air-tight chamber, wherein the time mathematical model of the air-tight chamber inflation/deflation comprises a time mathematical model of the air-tight chamber inflation and a time mathematical model of the air-tight chamber deflation;
determining the type and the number of the inflating tables and the time setting of the load spectrum according to the inflating time and the deflating time of the airtight cabin;
and establishing a virtual control loop, and performing multi-channel coordination control on the airtight test strength test.
Optionally, in the above method for multi-channel coordinated control of the large-volume aircraft airtightness strength test, an inflation valve of the inflation station is a proportional valve, and before the establishing of the multiple virtual control loops, the method further includes:
and calculating the sectional area of the inflation valve according to the real-time change of the sectional area of the proportional valve, and revising the calculation result of the inflation time.
Optionally, in the method for multi-channel coordinated control of the air tightness strength test of the large-volume aircraft as described above, the determining the gas flow state of the inflation/deflation valve includes:
when the airtight cabin is inflated, the pressure of the air source is set to be 8 atmospheric pressures, and the molecular free path of the inflation gas is as follows:
Figure BDA0002508868690000021
when the airtight cabin deflates, the pressure in the airtight cabin is not less than the atmospheric pressure, and the molecular free path of the deflated gas is as follows:
Figure BDA0002508868690000022
wherein the content of the first and second substances,
Figure BDA0002508868690000023
Figure BDA0002508868690000024
the mean free path of air at 20 ℃, and p is the gas pressure;
and determining that the gas flow state in the gas-tight cabin charging/discharging process is a viscous flow state according to the molecular free path of the inflation gas and the molecular free path of the discharging gas.
Optionally, in the method for multi-channel coordinated control of the airtight strength test of the large-volume aircraft as described above, the establishing a mathematical model of the time for inflating/deflating the airtight chamber and calculating the inflation time and deflation time of the airtight chamber includes:
according to the air-tight cabin inflation/deflation working principle, the air-tight cabin is arranged to be inflated/deflated through n inflation tables;
when the gas flowing state is viscous flow state and the airtight cabin is inflated, the flow rate of the gas flowing through the inflation inlet is as follows:
Figure BDA0002508868690000031
wherein A is the total sectional area of the air charging port of the airtight cabin, and P is1Is the pressure of the gas source, P2The pressure in the airtight cabin, R is a heat insulation index, R is a gas constant, M is a gas molar mass, and T is a gas temperature;
the time mathematical model for the air inflation of the airtight cabin is established as follows:
Figure BDA0002508868690000032
the time mathematical model for the air release of the airtight cabin is established as follows:
Figure BDA0002508868690000033
wherein V is the volume of the airtight cabin, and Q is the flow rate of gas flowing through the inflation inlet; the pressure inside the capsule is increased from P during the process of filling/deflating the capsule2Change to P3；
And calculating the inflation time and the deflation time of the airtight chamber according to the established time mathematical model of the inflation/deflation of the airtight chamber.
Optionally, in the above method for multi-channel coordinated control of an airtight strength test of a large-volume aircraft, when an inflation valve of the inflation station is a proportional valve, the calculating a cross-sectional area of the inflation valve and re-correcting a calculation result of an inflation time includes:
calculating and controlling the output system voltage as follows: v ═ P (PC-P)2)/FS*P*K；
Wherein V is the control system valve output voltage, and PC is the control systemUnified instruction, P2The pressure intensity in the airtight cabin is FS, the full range of the air pressure sensor is P, the control parameter is P, and the constant is K;
calculating the sectional area of the inflation valve as follows:
Figure BDA0002508868690000034
wherein A is0For the maximum sectional area of the inflation valve, the time for inflating the airtight chamber is corrected as follows: the time mathematical model of the air-tight chamber inflation combines the constraint condition of the cross section area A of the inflation valve.
Optionally, in the method for multi-channel coordinated control of the airtight strength test of the large-volume aircraft as described above, the determining the type and number of the inflation stations and the time setting of the load spectrum includes:
respectively comparing the calculated inflation time and deflation time with the test load spectrum setting time in the control system to judge whether the time setting of the load spectrum is reasonable or not;
and when the calculated inflation time and deflation time are greater than the setting time of the test load spectrum, increasing the number of the inflation tables, the model number of the inflation tables or the time setting of the load spectrum.
Optionally, in the multi-channel coordination control method for the airtightness strength test of the large-volume aircraft, a plurality of air pressure sensors are arranged in the airtight chamber for the test;
and the plurality of air pressure sensors are used for measuring the air pressure at different positions in the airtight cabin in the process of inflating/deflating the airtight cabin and outputting feedback values.
Optionally, in the above method for multi-channel coordinated control of an airtight strength test of a large-volume aircraft, the establishing of a virtual control loop to perform multi-channel coordinated control on the airtight strength test includes:
and establishing multiple virtual control loops of the air pressure sensor and the plurality of air inflation platforms, and taking the maximum value fed back by all the air pressure sensors as an input value called by each virtual control loop.
The multichannel coordination control method for the large-volume airplane airtight strength test provided by the embodiment of the invention comprises the steps of firstly analyzing the inflation/deflation working principle of the inflation platform and the inflation/deflation process of the airtight cabin, and judging the gas flow state of the inflation/deflation valve; establishing a mathematical model of the air-tight cabin inflation/deflation time to realize the calculation of the air-tight cabin inflation time and the air-tight cabin deflation time; aiming at the fact that an inflation valve of an inflation table used in the test is a proportional valve, considering real-time change of the sectional area of the proportional valve, calculating the sectional area of the inflation valve and revising the inflation time calculation result; combining the calculation of the inflation/deflation time, providing a basis for the selection of the model and the number of the inflation tables and the time setting of the load spectrum in the test control system; in the test control system, a virtual control loop calculated based on the air charging/discharging time is established, and multi-channel coordination control of the air-tight test is realized. The technical scheme of the embodiment of the invention provides a calculation scheme of the air inflation/deflation time of the large-volume airplane airtight strength test; the method provides a selection scheme of the type and the number of the inflating tables in the large-volume airplane airtight strength test and a scheme of time setting of a load spectrum in a test control system; and a virtual control loop based on charging/discharging time calculation is established, so that multichannel coordinated control of the large-volume airplane airtight strength test is realized, and the test control precision and the test efficiency are improved.
Drawings
The accompanying drawings are included to provide a further understanding of the invention and are incorporated in and constitute a part of this specification, illustrate embodiments of the invention and together with the example serve to explain the principles of the invention and not to limit the invention.
FIG. 1 is a flow chart of a multichannel coordinated control method for a large-volume aircraft airtightness strength test according to an embodiment of the present invention;
FIG. 2 is a schematic structural diagram of a gas tightness testing system for executing the multi-channel coordination control method provided by the embodiment of the invention;
FIG. 3 is a schematic view of the inflation principle for performing the air tightness strength test in the embodiment of the present invention;
FIG. 4 is a schematic diagram illustrating the operation of the air-tight chamber inflation/deflation process in accordance with an embodiment of the present invention;
FIG. 5 is a schematic view illustrating the control principle of the air-tightness strength test in the embodiment of the present invention;
fig. 6 is a schematic diagram of a screening algorithm used for a maximum feedback value in an embodiment of the present invention.
Detailed Description
In order to make the objects, technical solutions and advantages of the present invention more apparent, embodiments of the present invention will be described in detail below with reference to the accompanying drawings. It should be noted that the embodiments and features of the embodiments in the present application may be arbitrarily combined with each other without conflict.
The embodiment of the invention establishes a mathematical model of the air inflation/deflation time of the air tightness strength test of the large-volume airplane structure by researching the air inflation/deflation working principle of the air inflation platform and the air inflation/deflation process of the air tight cabin, provides a control method based on the calculation of the air inflation/deflation time, provides a virtual control loop, and realizes the multi-channel coordination control of the air tightness strength test of the large-volume airplane, thereby improving the test efficiency and the control precision.
The following specific embodiments of the present invention may be combined, and the same or similar concepts or processes may not be described in detail in some embodiments.
Fig. 1 is a flowchart of a multichannel coordinated control method for a large-volume aircraft airtightness strength test according to an embodiment of the present invention. The multichannel coordinated control method for the large-volume aircraft airtightness strength test provided by the embodiment can comprise the following steps:
step 1, determining the gas flow state of an inflation/deflation valve according to the inflation/deflation working principle of an inflation platform and the inflation/deflation process of an airtight cabin;
step 2, establishing a time mathematical model of the air-tight chamber inflation/deflation according to the determined gas flow state, and calculating the inflation time and the deflation time of the air-tight chamber, wherein the time mathematical model of the air-tight chamber inflation/deflation comprises a time mathematical model of the air-tight chamber inflation and a time mathematical model of the air-tight chamber deflation;
step 3, determining the type and the number of the inflating tables and the time setting of the load spectrum according to the inflating time and the deflating time of the airtight cabin;
and 4, establishing a virtual control loop, and performing multi-channel coordination control on the airtight test strength test.
Optionally, in the air tightness strength test of the large-volume aircraft according to the embodiment of the present invention, if the inflation valve of the inflation platform is a proportional valve, before step 3 is executed, the influence of the real-time change of the cross-sectional area of the proportional valve on the inflation time needs to be considered, so that the method may further include the following steps:
and 2a, calculating the sectional area of the inflation valve according to the real-time change of the sectional area of the proportional valve, and revising the calculation result of the inflation time.
Accordingly, the inflation time used as the judgment basis in step 3 in the embodiment of the present invention should be the inflation time corrected in step 2 a.
The multichannel coordination control method for the large-volume airplane airtight strength test provided by the embodiment of the invention comprises the steps of firstly analyzing the inflation/deflation working principle of the inflation platform and the inflation/deflation process of the airtight cabin, and judging the gas flow state of the inflation/deflation valve; establishing a mathematical model of the air-tight cabin inflation/deflation time to realize the calculation of the air-tight cabin inflation time and the air-tight cabin deflation time; aiming at the fact that an inflation valve of an inflation table used in the test is a proportional valve, considering real-time change of the sectional area of the proportional valve, calculating the sectional area of the inflation valve and revising the inflation time calculation result; combining the calculation of the inflation/deflation time, providing a basis for the selection of the model and the number of the inflation tables and the time setting of the load spectrum in the test control system; in the test control system, a virtual control loop calculated based on the air charging/discharging time is established, and multi-channel coordination control of the air-tight test is realized. The technical scheme of the embodiment of the invention provides a calculation scheme of the air inflation/deflation time of the large-volume airplane airtight strength test; the method provides a selection scheme of the type and the number of the inflating tables in the large-volume airplane airtight strength test and a scheme of time setting of a load spectrum in a test control system; and a virtual control loop based on charging/discharging time calculation is established, so that multichannel coordinated control of the large-volume airplane airtight strength test is realized, and the test control precision and the test efficiency are improved.
Fig. 2 is a schematic structural diagram of a gas tightness testing system for executing the multi-channel coordination control method according to the embodiment of the present invention. The airtightness testing system comprises: the gas-filling station comprises a gas-tight cabin, an inflating platform used for inflating the gas-tight cabin, a control system used for controlling the inflating platform and an air compression station used for providing an air source for the inflating platform. As shown in fig. 3, a schematic view of an inflation principle for performing an airtight strength test in an embodiment of the present invention is shown, where the control system in fig. 3 provides a control signal to the pressurization controller, so that the pressurization controller controls the pressurization table to inflate a test piece, where the test piece is an airtight chamber, and the air pressure sensor is located in the airtight chamber and is used to measure the air pressure at a corresponding position in the airtight chamber during the process of inflating/deflating the airtight chamber and output a feedback value. The following describes in detail an implementation manner of the above steps in the multichannel coordinated control method for the large-volume aircraft airtightness strength test according to the embodiment of the present invention with reference to the accompanying drawings.
(1) First, the charge/discharge gas flow state is judged.
In the step, the mean free path of the air at a constant temperature is inversely proportional to the pressure, and the mean free path of the air at 20 ℃ is as follows:
Figure BDA0002508868690000071
in the above-mentioned formula (1),
Figure BDA0002508868690000072
the mean free path of air at 20 ℃ is given in units of: meter (m), p is the gas pressure in pascals (Pa).
When the airtight cabin is inflated, the pressure of the air source is set to be 8 atmospheric pressures, and the molecular free path of the inflation gas is as follows:
Figure BDA0002508868690000073
when the airtight cabin deflates, the pressure in the airtight cabin is not less than the atmospheric pressure, and the molecular free path of the deflated gas is as follows:
Figure BDA0002508868690000074
according to the fact that the value of the mean free path during inflation and deflation is far smaller than the diameter of a valve hole of any inflation valve, the gas flowing state during inflation/deflation of the airtight chamber is a viscous flow state.
(2) And establishing a time mathematical model of the air-tight chamber inflation/deflation, and calculating the inflation time and the deflation time of the air-tight chamber.
Fig. 4 is a schematic diagram illustrating the operation of the air-tight chamber inflation/deflation process in the embodiment of the present invention. Assuming that the airtight cabin is inflated/deflated through n inflation platforms, the sectional area of each inflation port is A1，A2，A3，…，AnThen, the total sectional area of the inflation inlet of the airtight cabin is as follows:
A＝A1+A2+A3+…+An； (4)
among the parameters involved in the embodiments of the present invention, P0At atmospheric pressure of P1The pressure of the air source is shown, V is the volume of the airtight cabin, and Q is the flow rate of the air flowing through the inflation inlet. The pressure inside the capsule is increased from P during the process of filling/deflating the capsule2Change to P3. At a certain time t, the pressure in the capsule V is P2After dt times the pressure change in the capsule V is VdP2The gas flow rate from the gas charging port into the capsule container was Qdt, from which it was obtained:
VdP2＝Qdt； (5)
Figure BDA0002508868690000081
when the gas flowing state is viscous flow state and the airtight cabin is inflated, the flow rate of the gas flowing through the inflation inlet is as follows:
Figure BDA0002508868690000082
wherein A is the total cross-sectional area of the air charging port of the air-tight cabin and the unit is cubic meter (m)3)，P1Is the pressure of gas source and has the unit of Pa, P2Is the pressure in the airtight chamber, and has the unit of Pa, R is the adiabatic index, R is the gas constant of 8.3143J/[ K.mol ]]M is qiThe unit of the molar mass is: kg/mol, T is the gas temperature and the unit is K; the unit of the flow rate Q of the gas flowing through the charging port is Pa.m3/s。
By substituting formula (7) for formula (6), it is possible to obtain:
Figure BDA0002508868690000083
integrating the two sides of equation (8) to obtain:
Figure BDA0002508868690000091
the airtight chamber is in an initial state P2And the end of capsule state P3Substituting the formula into the formula, the time mathematical model for inflating the airtight cabin can be obtained as follows:
Figure BDA0002508868690000092
the time of inflation of the capsule can be calculated from the mathematical model of the time of inflation of the capsule of equation (10).
Similarly, a mathematical model of the time of the capsule deflation can be obtained as:
Figure BDA0002508868690000093
equation (11) cannot be integrated and the deflation time can be solved by Matlab programming using the principles of discrete processing and approximate summation.
(3) And correcting the calculation result of the inflation time.
If the inflation valve of the inflation platform used in the airtight strength test is a proportional valve, the inflation time calculation formula (10) also needs to take the real-time change of the sectional area of the proportional valve into account, and the implementation mode of revising the inflation time is as follows:
firstly, calculating and controlling the output system voltage as follows:
V＝(PC-P2)/FS*P*K； (12)
wherein V is a control systemThe output voltage of the system valve is volt (V), and PC is the current command (kPa), P of the control system2The pressure in the airtight chamber (kPa), FS is the full-scale range (kPa) of the air pressure sensor, P is a control parameter, and K is a constant.
Then calculating the sectional area of the inflation valve as follows:
Figure BDA0002508868690000101
in the formula (13), A0For the maximum sectional area of the inflation valve, the time for inflating the airtight chamber is corrected as follows: the time mathematical model of the air-tight chamber inflation combines the constraint condition of the cross section area A of the inflation valve. That is, by substituting equation (13) into equation (10), the corrected airtight chamber inflation time can be calculated.
(4) The model and number of the inflatable stations, and the time setting of the load spectrum are determined.
In the embodiment of the invention, the calculated air charging/discharging time is respectively compared with the setting time of the test load spectrum in the air tightness test control system, and whether the time setting of the load spectrum is reasonable or not is judged; if the calculated inflation/deflation time is longer than the setting time of the load spectrum, the time setting of the load spectrum is unreasonable, and the system performance of the airtight strength test can be improved by increasing the number of the inflation tables, increasing the models of the inflation tables or increasing the time setting of the load spectrum.
(5) And establishing a virtual control loop to realize multi-channel coordination control on the airtight test strength test.
As shown in fig. 2 and 4, in the capsule according to the embodiment of the present invention, a plurality of air pressure sensors are provided; these pressure sensors are used to measure the pressure at different locations within the capsule during the capsule inflation/deflation process and to output feedback values. In addition, multiple virtual control loops of the air pressure sensor and a plurality of air inflation stations can be established through the air pressure sensors, and the maximum value fed back by all the air pressure sensors is used as an input value called by each virtual control loop.
In the embodiment of the invention, in order to ensure that servo control signals of a plurality of air inflation tables are consistent and avoid the problem that the air inflation tables are not synchronous in action in an airtight test, only one value can be screened out from feedback values of a plurality of paths of air pressure sensors to participate in closed loop control, a virtual channel is established in a test control system, and the input of the plurality of virtual channels calls the same air pressure feedback value in the process of test air inflation/deflation, as shown in fig. 5, the method is a schematic control principle diagram of the airtight strength test in the embodiment of the invention. The same feedback value called by the virtual input is the maximum value among all the feedback of the air pressure sensors, and the maximum feedback value screening can be performed by means of a digital output editor of the air tightness test control system, as shown in fig. 6, which is a schematic diagram of a screening algorithm adopted by the maximum feedback value in the embodiment of the invention.
Although the embodiments of the present invention have been described above, the above description is only for the convenience of understanding the present invention, and is not intended to limit the present invention. It will be understood by those skilled in the art that various changes in form and details may be made therein without departing from the spirit and scope of the invention as defined by the appended claims.

Claims (8)

1. A multichannel coordinated control method for a large-volume airplane airtight strength test is characterized by comprising the following steps:
determining the gas flow state of the inflation/deflation valve according to the inflation/deflation working principle of the inflation platform and the inflation/deflation process of the airtight cabin;
establishing a time mathematical model of the air-tight chamber inflation/deflation according to the determined gas flow state, and calculating the inflation time and the deflation time of the air-tight chamber, wherein the time mathematical model of the air-tight chamber inflation/deflation comprises a time mathematical model of the air-tight chamber inflation and a time mathematical model of the air-tight chamber deflation;
determining the type and the number of the inflating tables and the time setting of the load spectrum according to the inflating time and the deflating time of the airtight cabin;
and establishing a virtual control loop, and performing multi-channel coordination control on the airtight test strength test.
2. The method for multi-channel coordinated control of the airtightness strength test of the large-volume aircraft according to claim 1, wherein the inflation valve of the inflation platform is a proportional valve, and before the establishment of the multiple virtual control loops, the method further comprises:
and calculating the sectional area of the inflation valve according to the real-time change of the sectional area of the proportional valve, and revising the calculation result of the inflation time.
3. The multi-channel coordinated control method for the air tightness strength test of the large-volume airplane according to claim 2, wherein the determining the gas flow state of the air inflation/deflation valve comprises the following steps:
when the airtight cabin is inflated, the pressure of the air source is set to be 8 atmospheric pressures, and the molecular free path of the inflation gas is as follows:
Figure FDA0002508868680000011
when the airtight cabin deflates, the pressure in the airtight cabin is not less than the atmospheric pressure, and the molecular free path of the deflated gas is as follows:
Figure FDA0002508868680000012
wherein the content of the first and second substances,
Figure FDA0002508868680000013
Figure FDA0002508868680000014
the mean free path of air at 20 ℃, and p is the gas pressure;
and determining that the gas flow state in the gas-tight cabin charging/discharging process is a viscous flow state according to the molecular free path of the inflation gas and the molecular free path of the discharging gas.
4. The method for multi-channel coordinated control of airtight strength test of large volume aircraft according to claim 3, wherein said establishing a time mathematical model of the airtight chamber inflation/deflation and calculating the time of inflation and deflation of the airtight chamber comprises:
according to the air-tight cabin inflation/deflation working principle, the air-tight cabin is arranged to be inflated/deflated through n inflation tables;
when the gas flowing state is viscous flow state and the airtight cabin is inflated, the flow rate of the gas flowing through the inflation inlet is as follows:
Figure FDA0002508868680000021
wherein A is the total sectional area of the air charging port of the airtight cabin, and P is1Is the pressure of the gas source, P2The pressure in the airtight cabin, R is a heat insulation index, R is a gas constant, M is a gas molar mass, and T is a gas temperature;
the time mathematical model for the air inflation of the airtight cabin is established as follows:
Figure FDA0002508868680000022
the time mathematical model for the air release of the airtight cabin is established as follows:
Figure FDA0002508868680000023
wherein V is the volume of the airtight cabin, and Q is the flow rate of gas flowing through the inflation inlet; the pressure inside the capsule is increased from P during the process of filling/deflating the capsule2Change to P3；
And calculating the inflation time and the deflation time of the airtight chamber according to the established time mathematical model of the inflation/deflation of the airtight chamber.
5. The multichannel coordinated control method for the airtight strength test of the large-volume aircraft according to claim 4, wherein when the inflation valve of the inflation platform is a proportional valve, the calculation of the cross-sectional area of the inflation valve and the re-correction of the calculation result of the inflation time comprise:
calculating and controlling the output system voltage as follows: v ═ P (PC-P)2)/FS*P*K；
Wherein V is the control system valve output voltage, PC is the control system current command, P2The pressure intensity in the airtight cabin is FS, the full range of the air pressure sensor is P, the control parameter is P, and the constant is K;
calculating the sectional area of the inflation valve as follows:
Figure FDA0002508868680000031
wherein A is0For the maximum sectional area of the inflation valve, the time for inflating the airtight chamber is corrected as follows: the time mathematical model of the air-tight chamber inflation combines the constraint condition of the cross section area A of the inflation valve.
6. The multi-channel coordinated control method for the airtightness strength test of the large-volume aircraft according to claim 5, wherein the determining of the type and number of the inflating tables and the time setting of the load spectrum comprises:
respectively comparing the calculated inflation time and deflation time with the test load spectrum setting time in the control system to judge whether the time setting of the load spectrum is reasonable or not;
and when the calculated inflation time and deflation time are greater than the setting time of the test load spectrum, increasing the number of the inflation tables, the model number of the inflation tables or the time setting of the load spectrum.
7. The multi-channel coordination control method for the air tightness strength test of the large-volume airplane according to any one of the claims 1 to 6, characterized in that a plurality of air pressure sensors are arranged in an air chamber for the test;
and the plurality of air pressure sensors are used for measuring the air pressure at different positions in the airtight cabin in the process of inflating/deflating the airtight cabin and outputting feedback values.
8. The multi-channel coordinated control method for the airtight strength test of the large-volume aircraft as claimed in claim 7, wherein the establishing of the virtual control loop for the multi-channel coordinated control of the airtight strength test comprises:
and establishing multiple virtual control loops of the air pressure sensor and the plurality of air inflation platforms, and taking the maximum value fed back by all the air pressure sensors as an input value called by each virtual control loop.
CN202010454578.XA 2020-05-26 2020-05-26 Multichannel coordination control method for large-volume airplane airtight strength test Pending CN111487872A (en)

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Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN112696374A (en) * 2020-11-16 2021-04-23 南京航空航天大学 Air pressure simulation system of aircraft engine surge signal and control method thereof
CN115061519A (en) * 2022-06-28 2022-09-16 中国飞机强度研究所 High-precision control system and method for multi-thermal-field simulation for testing strength of aerospace plane

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
吝继锋等: "气密舱充放气时间计算方法研究", 《测控技术》 *

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN112696374A (en) * 2020-11-16 2021-04-23 南京航空航天大学 Air pressure simulation system of aircraft engine surge signal and control method thereof
CN115061519A (en) * 2022-06-28 2022-09-16 中国飞机强度研究所 High-precision control system and method for multi-thermal-field simulation for testing strength of aerospace plane

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