CN113701982A

CN113701982A - Measurement and control method of heat storage heater for wind tunnel experiment

Info

Publication number: CN113701982A
Application number: CN202110987251.3A
Authority: CN
Inventors: 高占彪; 顾洪斌; 黄河激; 岳连捷
Original assignee: Institute of Mechanics of CAS
Current assignee: Institute of Mechanics of CAS
Priority date: 2021-08-26
Filing date: 2021-08-26
Publication date: 2021-11-26
Anticipated expiration: 2041-08-26
Also published as: CN113701982B

Abstract

The invention belongs to the technical field of aerospace ground test equipment, and discloses a measurement and control method of a heat storage heater for a wind tunnel experiment, aiming at the technical problem of low safety of test equipment in the prior art, which specifically comprises the following steps: starting; opening a smoke exhaust system and a sewage discharge system, closing a cold air inlet valve, and opening a working medium supply system; starting the gas supply process of an igniter of the gas burner, and judging whether the gas supply process reaches a preset pressure or not; switching on a power supply and judging whether the pressure of the igniter reaches a preset value or not; starting a main flame working process of the burner; judging whether the flame detector gives an alarm or not, and entering a corresponding step; judging whether the pressure of the igniter reaches a preset value or not, or entering a step of restarting the igniter; starting a heat accumulation burner to adjust working conditions; closing the smoke exhaust system and the sewage discharge system in sequence, and opening the cold air inlet valve; and (6) ending. The automatic operation of the heat storage heater can be realized, the reliability and the safety of the system are improved, and the possibility of accidental events is reduced.

Description

Measurement and control method of heat storage heater for wind tunnel experiment

Technical Field

The invention belongs to the technical field of aerospace ground test equipment, and particularly relates to a measurement and control method of a heat storage heater for a wind tunnel experiment.

Background

The pure air wind tunnel can provide relatively clean high enthalpy gas incoming flow, is indispensable equipment for ground test of the hypersonic aircraft, and is widely accepted internationally. However, due to the technical difficulty, the purified air tunnels developed at home and abroad are very few. The heat storage heater is one of the key devices, and how to realize the stable combustion of the heat storage heater with large ratio variable power is inevitably the technical difficulty of the design of the heat storage heater. The prior technical method is that a manual and remote control method is adopted, and a tester remotely operates the heat storage heater in a control room through a distributed control system. The method is simple and clear, and can enable a tester to adjust the working state of the heat accumulator in time. But the disadvantages are obvious:

1) the emergency response of manual regulation is not enough, the heat storage heater has a complex structure, the control part is dispersed, the number of related signals is large, the types are multiple, the manual regulation is difficult to correspond to the emergency situation, the randomness of the accidental event is increased, and the safety of the test equipment is reduced.

2) The transition depends on the professional quality of the tester, and the tester needs to be skilled in the aspects of the thermal storage heater.

3) The method has the advantages that the physical quality of testers is greatly tested, the preheating process generally lasts for more than 40 hours, the testers need to be highly concentrated in the preheating process to deal with sudden situations, and the energy and physical strength of the testers are greatly consumed.

Disclosure of Invention

Aiming at the technical problems that manual regulation in the prior art is difficult to correspond to emergency situations and the safety of test equipment is reduced, the invention aims to provide a measurement and control method of a heat storage heater for a wind tunnel experiment, which can realize automatic operation of the heat storage heater, provide technical guarantee for safe operation of the wind tunnel, improve the reliability and safety of a system and reduce the possibility of accidental events.

The technical scheme adopted by the invention is as follows:

a measurement and control method of a heat storage heater for a wind tunnel experiment is applied to a preheating stage of a heat storage type pure air wind tunnel, and specifically comprises the following steps:

s00: beginning: the test enters an automatic operation stage;

s10: opening a smoke exhaust system and a blowdown system, closing a cold air inlet valve, and sequentially opening an empty point way and a natural gas point way of a working medium supply system, and one valve for each branch of a natural gas main way and an air main way and one valve for each way of an oxygen supplementing way;

s20: sequentially opening a dead point valve and a natural gas circuit valve, and judging whether the respective pressures reach preset pressures;

s30: switching on a power supply and judging whether the pressure of the igniter reaches a preset value or not;

s40: synchronously opening the main air valve, the natural gas branches and the oxygen supplementing valve according to a preset program, and setting pressure parameters of the pressure regulating valves according to preset values;

s50: judging whether the flame detector gives an alarm or not, and entering a corresponding step;

s60: judging whether the pressure of the igniter reaches a preset value or not, or entering a step of restarting the igniter;

s70: changing and adjusting parameters of the pressure regulating valve according to a preset value or a preset curve so as to change the flow and further change the flame power; the heat accumulation temperature detection system judges whether the heat accumulator reaches the required temperature gradient;

s80: sequentially zeroing pressure regulating valves of all branches of the natural gas main path, the oxygen supplementing path and all branches of the air main path, sequentially closing two and one valves of all branches of the natural gas main path, the oxygen supplementing path and all branches of the air main path, a smoke exhaust system and a blowdown system, and opening a cold air inlet valve;

s90: and (4) ending: and (5) finishing the heat storage process and entering a waiting stage of a wind tunnel test.

Further, the working medium supply system comprises a natural gas point path, an air point path, a natural gas main path, an air main path, an oxygen supplementing path, a cooling air path, a pressure sensor and a flame detector;

the front and the back of each pressure regulating valve of the natural gas point way, the air point way, the natural gas main way, the air main way, the oxygen supplementing way and the cooling air way are respectively provided with a stop valve which is a valve (a first switch valve) of each way and a valve (a second switch valve) of each way; a valve, two valves are pneumatic stop valves, set up the aim at of twice stop valves, prevent that one stop valve from becoming invalid, cause gas leakage.

The natural gas point way and the air point way are respectively connected with the igniter, and natural gas and air with constant flow are conveyed to the igniter through the natural gas point way and the air point way;

the natural gas main path, the air main path and the oxygen supplementing path are respectively connected with the main burner, the wide-range flow is adjusted through the natural gas main path and the air main path, and the oxygen supplementing path provides oxygen input for the heat storage heater under the ultra-high temperature working condition.

The cooling air path is connected with the combustor cooling channel; the total pressure of the igniter is measured through a pressure sensor, and the main flame of the burner is detected through a flame detector.

Furthermore, the natural gas point way and the air point way are arranged in the same structure and respectively comprise a gas transmission pipeline, a sensor, a pressure reducing valve, a throttling device and a check valve, wherein the sensor is arranged in front of a valve of the pipeline and measures the pressure of a gas source through the sensor; the pressure reducing valve is arranged between a valve and a two valve, the rear end of the two valves is connected with a throttling device, the tail end of the gas transmission pipeline close to the burner interface is connected with a check valve, and the downstream of the check valve is connected with an igniter of the burner; the natural gas main path and the air main path comprise a plurality of branches with different flow coefficients, and the branches are increased or decreased according to actual needs; each branch is provided with a regulating valve and is synchronously opened, the regulating valve and a downstream pressure sensor form a closed-loop control loop, and the regulating valves are adjusted in real time according to parameters given by a control system.

The regulating valves are synchronously opened, so that the advantage of the synchronous opening of the regulating valves is that large-flow air and natural gas can simultaneously enter the combustor to be rapidly combusted. The high-flow air is prevented from entering early and the temperature is too low; or the impact of the overlarge temperature difference on the heat accumulator under the conditions that the mass flow natural gas advances early to generate high-temperature flame and the like.

The oxygen supplementing path is specially arranged for the heat accumulator under the condition of ultra-high temperature, and the opening time and pressure are determined according to the requirement of the test working condition.

Further, in step S10, the smoke exhaust valve system and the blow-down valve are opened, the cold air intake valve is closed, and one valve is opened in each path of the working medium supply system in sequence, and the process is set as a sequentially executed process, which is irreversible, and is logically interlocked in front and back. This has the advantage that the exhaust system, the blow down valve, is preferably opened, followed by the air, natural gas valves in sequence. The heat storage tank is ensured to be in a normal pressure or even negative pressure environment, and the successful ignition of the burner is ensured.

Further, in step S80, the natural gas branch, the measurement and control branch valve, one valve for each branch, the smoke exhaust system, the blowdown valve, and the cold air intake valve are sequentially closed, and the process is set as a sequentially executed process, and is irreversible and logically interlocked.

Further, the step S20 is set as an air supply process of the igniter of the gas burner, the idle point 2 valve is firstly opened, the measurement and control system judges whether the pressure signal reaches a preset value P1 or not according to the pressure signal, and the operation is directly interrupted if the pressure signal does not reach the preset value P1; otherwise, continuing to open the natural gas point-path 2 valve, judging whether the natural gas point-path reaches a preset value P2 by the measurement and control system according to the pressure signal, if the natural gas point-path does not reach the preset value P2, directly interrupting the operation, and if not, entering the step S30.

Further, in the step S30, the spark plug is powered on, and the measurement and control system determines whether the ignition is successful according to the pressure signal P3, if so, the step S40 is performed, otherwise, the step S50 is performed.

Preferably, the pressure judgment of the empty point circuit, the natural gas circuit and the igniter is respectively provided with limited time t1, t2 and t3, which are respectively given according to the time of the pressure establishment of each circuit. The advantage of this is that it is determined quickly during the test run whether the operating conditions of the igniter are met, and if so, the igniter is ignited quickly, and if not, the gas supply is cut off as soon as possible. Avoid a large amount of combustible gas to get into in the heat accumulation jar, take place danger. In addition, the first opening of the empty point way and the second opening of the natural gas point way are also processes which are sequentially executed and logically interlocked. When the flow rate of the idle point is not reached, natural gas enters the igniter, and the flame temperature of the igniter is prevented from being too high. After the igniter is successfully ignited for t4 time, the spark plug is powered off.

Further, the step S40 is configured as a main flame working process of the burner, and the main air branch and the natural gas branch are sequentially opened, and the main air branch and the natural gas path regulating valves are synchronously opened according to preset parameters given by the measurement and control system, and respectively determine whether the respective pressures reach preset values; the flame detector detects whether the heater is normally combusted intermittently, and the working time interval of the flame detector is t 5; if the detector does not alarm, continuing to S80; if the detector alarms, proceed directly to S50.

Further, the step S50 is that the measurement and control system directly reverses to the step S30 to determine whether the pressure of the igniter reaches the preset value P3, if the preset value is met, the system is kept without operation within the time t6, and waits for whether the alarm of the flame detector disappears, otherwise, the step S80 is performed, and the step S80 is performed; if no more alarm is given, the process proceeds to step S70. The advantage of setting the waiting time t6 is that in the case of a normal operation of the burner, it prevents erroneous judgments of the flame detector, which would cause unnecessary parking losses.

Further, the step S60 is an operation step taken when the pressure of the igniter is lower than a preset value after the regenerative burner operates normally, the pressure regulating valves of the main natural gas path and the main air path are sequentially set to 0, the valve 2 of the natural gas point is closed, the step S20 of opening the valve of the natural gas path is entered again, the time limit of restarting the igniter path is t7, and if the time is out, the step S80 of stopping the igniter fails to be entered directly.

Further, the step S00 is a test starting step, and the step S00 selects any one of a full manual mode, a semi-automatic mode, and a full automatic mode. The full manual mode is that a person can operate the system without any restriction; the semi-automatic mode is that the whole test flow is designed in advance, and the tester can only set parameters of each path of regulating valve under the prompting condition of the system; the full-automatic mode, that is, the whole test flow is designed in advance, and comprises parameter setting of each path of regulating valve. The advantage of such a design is that it is flexible and versatile, with a step-by-step progression. At the initial debugging stage of the heat storage heater, the worker can conveniently find out the performance of the heat storage heater; when the heat storage heater is in formal operation, the test process can be solidified, and the system safety and the operation stability of the heat storage heater are greatly improved.

The step S70 is set as the regenerative burner turn-on phase, and according to the step S00, the step S70 is classified as the semi-automatic mode or the full-automatic mode. In a semi-automatic mode, parameters of regulating valves such as branches of the air main path and the natural gas main path, the oxygen supplementing path and the like are set by workers only in an adjustable mode. Under the full-automatic mode, the change curve of the flow parameter or the flow along with the time is prefabricated, and the system runs in a full-automatic mode until the heat storage temperature detection system detects that the heat storage body meets the requirements in real time.

When the valves are opened or closed in sequence, the interval time is set as t1, each valve or actuating mechanism is transmitted to the measurement and control system through a feedback signal, and the signal is not used as the judgment basis for program execution. The advantage of setting up like this lies in, observes and controls system and staff can be clear know whether valve or actuating mechanism move in place, has avoided repeated setting judgment condition again, leads to the logic confusion, increases system operation unstability.

Furthermore, a measurement and control device of a heat storage heater for a wind tunnel experiment is adopted, the control device comprises a working medium supply system, a burner, a heat storage body, a heat storage temperature detection system, a cold air inlet valve, a smoke exhaust system and a sewage discharge system, the heat storage body is vertically arranged on a support frame of a heat storage well, the burner is arranged at the top of the heat storage body through flange connection, and each air supply channel of the working medium supply system is connected with a burner interface through a high-temperature hose; the heat storage temperature detection system is arranged in the heat storage body and is used for detecting the temperature; the cold air inlet valve, the smoke exhaust system and the sewage discharge system are arranged at the lower part of the heat storage body.

The invention has the beneficial effects that:

(1) the measurement and control method can select a full-manual mode, a semi-automatic mode and a full-automatic mode. The full-manual mode, the semi-automatic mode and the full-automatic semi-automatic mode are switched, and the debugging of workers is facilitated; under the semi-automatic mode, corresponding safety interlocking setting is carried out, so that the working personnel can conveniently search the performance of the heat storage heater; in a full-automatic mode, the test process can be solidified, and the system safety and the running stability of the heat storage heater are greatly improved.

(2) The measurement and control method is flexible, variable, gradually propelled, flexible and visual, greatly reduces development time required by system design, and improves wind tunnel test quality and efficiency.

(3) The measurement and control method has clear principle, simple structure, easy realization and extremely high application value.

Drawings

FIG. 1 is a schematic view of the operation of a regenerative heater according to the present invention;

FIG. 2 is a step diagram of a measurement and control method of a thermal storage heater for a wind tunnel test according to the present invention;

FIG. 3 is a schematic diagram of a working medium supply system according to the present invention;

FIG. 4 is a graph of experimental data for an example of the present invention;

wherein, 1, a working medium supply system; 2. a burner; 3. a heat storage body; 4. a thermal storage temperature detection system; 5. a cold air intake valve; 6. a smoke exhaust system; 601. a smoke exhaust valve; 602. a fan; 603. a differential pressure sensor; 7. a blowdown system; 8. a flame detector;

00. an igniter; 01. a flame detector; 17. a pressure sensor;

11. a sensor a; 12. a sensor c; 13. a sensor k; 14. a sensor b; 15. a sensor i; 16. a sensor d;

21. a valve a; 22. a valve c; 23. a valve f; 24. a valve b; 25. a valve e; 26. a valve d;

31. a pressure reducing valve a; 32. a pressure reducing valve b;

41. a pressure regulating valve c; 42. a pressure regulating valve d; 43. a pressure regulating valve h; 44. a pressure regulating valve g; 45. a pressure regulating valve e; 46. a pressure regulating valve f;

51. a sensor e; 52. a sensor f; 53. a sensor j; 54. a sensor g; 55. a sensor h; 56. a sensor l;

61. a valve a; 62. a valve c; 63. a valve d; 64. a valve g; 65. a valve b; 66. a valve f; 67. a second valve e; 68. a valve f;

71. a throttling device a; 72. a throttling device c; 73. a throttling device d; 74. a throttling device h; 75. a throttling device b; 76. a throttling device g; 77. a throttling device e; 78. a throttle device f;

81. a check valve c; 82. a check valve a; 83. a check valve b; 84. a check valve e; 85. a check valve d;

91. an on-off valve b; 92. and (c) opening and closing the valve.

Detailed Description

Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings.

According to the requirements of wind tunnel tests, the heat storage heater needs to provide high-temperature and high-pressure airflow with the temperature of 1200K-1600K, and alumina is selected as a porous heat storage ceramic material for realizing the technical requirements, wherein the accumulation volume is 0.8 meter in diameter and 5 meters in height. Due to the cold and heat shock resistant nature of alumina, it is required that the temperature rise per hour not exceed 80 ℃. The operation of the burner 2 of the example was atmospheric combustion, i.e., the combustion pressure was 0.1 MPa. The power of the combustor 2 is about 600kW, and the flow and pressure of each path of the working medium supply system are arranged as follows:

the following is specifically illustrated with reference to the examples:

example 1

As shown in fig. 2, a measurement and control method for a heat storage heater for a wind tunnel experiment is characterized in that the measurement and control method is applied to a preheating stage of a heat storage type pure air wind tunnel, and specifically comprises the following steps:

s00: starting; the test enters an automatic operation stage;

s10: opening a smoke exhaust system and a blow-down valve, closing a cold air inlet valve, and sequentially opening one valve in each path of a working medium supply system;

s30: electrifying the spark plug and judging whether the pressure of the igniter reaches a preset value;

s40: synchronously opening each branch of the air main, the natural gas and the oxygen according to a preset program, and setting the pressure of each pressure regulating valve according to a preset value;

s80: sequentially zeroing a natural gas branch and an air branch pressure regulating valve, sequentially closing a second valve and a first valve of each branch, a smoke exhaust system and a blow-down valve, and opening a cold air inlet valve;

In another embodiment of the present invention, as shown in fig. 2, the step S00 is a test starting step, and the step may select a full manual mode, a semi-automatic mode, and a full automatic mode; the step S70 is selected according to the step S00. The system can be operated in a full manual mode, namely, under the condition that testers can not be restricted; the semi-automatic mode, namely the whole test flow is designed in advance, and the tester can only set parameters of each path of regulating valve under the condition of system prompt when the tester enters the step S70; the full-automatic mode, that is, the whole test flow is designed in advance, and comprises parameter setting of each path of regulating valve. The advantage of such a design is that it is flexible and versatile, with a step-by-step progression. In the initial debugging stage of the heat storage heater, the performance of the heat storage heater is convenient for a tester to grope; when the heat storage heater is in formal operation, the test process can be solidified, and the system safety and the operation stability of the heat storage heater are greatly improved.

In another embodiment of the present invention, as shown in fig. 2, the step S10 of opening the smoke exhaust valve system, the blow-down valve, closing the cool air intake valve, and opening one valve for each channel of the working medium supply system in sequence is a sequentially executed process, which is irreversible and logically interlocked. This has the advantage that in the smoke evacuation system, the blow-down valve is preferably opened, followed by the sequential opening of the empty point, natural gas point and the valve. The heat accumulation tank is ensured to be in a normal pressure or even negative pressure environment, and the successful ignition of the combustor 2 is ensured.

Furthermore, when a plurality of valves are opened or closed in sequence, the interval time is set to be 0.2s according to the opening and closing attributes of the system valves, each valve or actuating mechanism of the invention has a feedback signal to be transmitted to the measurement and control system, but the signals are not used as the judgment basis for program execution. The advantage of setting up like this lies in, observes and controls system and staff can be clear know whether valve or actuating mechanism move in place, has avoided repeated setting judgment condition again, leads to the logic confusion, increases system operation unstability.

In another embodiment of the present invention, as shown in fig. 2, in step S20, for the gas supply process of the igniter of the burner 2, firstly, the idle point valve is opened, and the measurement and control system determines whether the pressure signal reaches a preset value of 3.45MPa, if the pressure signal does not reach the preset value, the operation is directly interrupted; otherwise, the natural gas point-to-point valve is continuously opened, the measurement and control system judges whether the empty point-to-point valve reaches the preset value of 1.40MPa according to the pressure signal, if the pressure signal does not reach the preset value, the operation is directly interrupted, and if the pressure signal does not reach the preset value, the step S30 is executed.

In another embodiment of the present invention, as shown in fig. 2, in step S30, the spark plug is powered on, and the measurement and control system determines whether the ignition is successful according to the pressure value 1.3MPa, if so, the step S40 is performed, otherwise, the step S50 is performed.

Preferably, the pressure judgment of the empty point path, the natural gas path and the igniter sets the limited time of 1s, 0.8s and 1.5s respectively, and the limited time is given according to the time of pressure establishment of each path. The advantage of this is that it is determined quickly during the test run whether the operating conditions of the igniter are met, and if so, the igniter is ignited quickly, and if not, the gas supply is cut off as soon as possible. Avoid a large amount of combustible gas to get into in the heat accumulation jar, take place danger. In addition, the first opening of the empty point way and the second opening of the natural gas point way are also processes which are sequentially executed and logically interlocked. When the flow rate of the idle point is not reached, natural gas enters the igniter, and the flame temperature of the igniter is prevented from being too high. And after the igniter is successfully ignited for 5s, the spark plug is powered off.

In another embodiment of the present invention, as shown in fig. 2, the step S40 is a main flame operation process of the burner 2. Firstly, opening two valves of each branch of the main air circuit and each branch of the natural gas circuit in sequence, synchronously opening adjusting valves of each branch of the main air circuit and each branch of the natural gas circuit according to preset parameters given by a measurement and control system, and respectively judging whether the pressure of each branch reaches a preset value. The flame detector detects whether the heater is normally burnt or not intermittently, and the working time interval of the flame detector is 5 s. If the detector does not alarm, continuing to S80; if the detector alarms, proceed directly to S50.

In another embodiment of the present invention, as shown in fig. 2, the step S50 is to directly reverse the measurement and control system to the step S30 to determine whether the pressure of the igniter reaches the preset value of 1.3MPa, if the pressure of the igniter meets 1.3MPa, the system is not operated within 20S, and waits for whether the alarm of the flame detector disappears, otherwise, the process only goes to the step S80, and then goes to the parking step; if no more alarm is given, the process proceeds to step S70. The advantage of setting the waiting time 20s is that in the case of a normal operation of the burner 2, erroneous judgments of the flame detector are prevented, causing unnecessary parking losses.

In still another embodiment of the present invention, as shown in fig. 2, in step S60, after the regenerative burner 2 is working normally, the igniter pressure is lower than the preset value. And sequentially setting the pressure regulating valves of the branches of the natural gas main line and the empty main line to be 0, and closing the natural gas point valve. And S20, the step of opening the natural gas circuit valve is carried out again, the time for restarting the igniter circuit is limited to 8S, if the time is over, the igniter is failed to restart, and the step of stopping the vehicle directly enters S80.

In another embodiment of the present invention, as shown in fig. 2, the step S70 is a duty-adjusted stage of the regenerative combustor 2. When the step S00 is set to be in the semi-automatic mode, a tester can only change the parameter setting of each pressure regulating valve; when the step S00 is set to the full-automatic mode, the flow parameter or the change curve of the flow with time is set to be prefabricated, and the thermal storage heater is operated fully automatically until the thermal storage temperature detection system detects that the thermal storage body meets the requirement in real time.

In another embodiment of the present invention, as shown in fig. 2, in step S80, the pressure regulating valves of the branches of the natural gas point way and the air point way, the valves of the branches, the smoke exhaust system and the blow-down valve, and the cold air intake valve are closed in sequence. This is a sequentially executed process, irreversible, and logically interlocked.

And step S90, finishing the heat storage process and entering a wind tunnel test waiting stage.

Furthermore, the regulating valves are opened synchronously, so that the advantage of this is that large flow of air and natural gas enters the combustor 2 at the same time for rapid combustion. The high-flow air is prevented from entering early and the temperature is too low; or the impact of the overlarge temperature difference on the heat accumulator under the conditions that the mass flow natural gas advances early to generate high-temperature flame and the like.

Furthermore, the oxygen path is specially arranged under the ultra-high temperature working condition of the heat storage heater, and the opening time and the pressure are determined according to the test requirements.

Furthermore, each branch of the air main path, the natural gas path regulating valve and the downstream pressure sensor form a closed-loop control loop, and the regulating valve is adjusted in real time according to parameters given by the measurement and control system.

On the basis of the above embodiment 1, a further embodiment of the present invention, as shown in fig. 3, includes a natural gas point line and an air point line for the igniter 00; the main natural gas path and the main air path (air path for short) for the main burner 2, which can be used for wide-range flow regulation, are used for cooling air paths (air cooling for short) for cooling the burner body, and are used for oxygen supply paths (oxygen paths for short) under the ultra-high temperature working condition. The device also comprises a pressure sensor 17 for measuring the total pressure of the igniter, a flame detector 01 for detecting the main flame of the burner 2, and a PLC-based control system.

The natural gas point way and the air point way of the embodiment have the same structure.

The natural gas point circuit comprises a gas pipeline for conveying working media, a sensor a11 for measuring the pressure of a gas source is arranged in front of a valve a21, a pressure reducing valve a31 is arranged between the valve a21 and the valve a61, the rear end of the valve a61 is connected with a throttling device a71, the tail end of the gas pipeline, which is close to a connector of the combustor 2, is respectively connected with a check valve a82, and the downstream of the check valve a82 is connected with the combustor 2.

The air point way comprises an air pipeline for conveying working media, a sensor b14 for measuring air source pressure is arranged in front of a valve b24, a pressure reducing valve b32 is arranged between two stop valves, the rear end of the valve b65 is connected with a throttling device b75, the tail end of the air pipeline is close to the interface of the combustor 2 and is connected with a check valve b83, and the downstream of the check valve b83 is connected with the combustor 2.

In another embodiment of the present invention, as shown in fig. 3, the igniter according to this embodiment is a fixed power igniter, and the natural gas point and the empty point only need to output media with fixed flow and pressure, so the natural gas point and the empty point are designed as fixed value pressure reducing valves, and the computer control system controls the switch of the switch valve to turn on and off the output of the media. The advantages of this are that the control loop is reduced, the structure is simplified, the reliability of the system is improved and the cost is reduced.

In another embodiment of the present invention, as shown in fig. 3, the main natural gas path in this embodiment includes two branches with different flow coefficients, the main natural gas path includes a pipeline for conveying working media, a sensor c12 for measuring gas source pressure is disposed in front of a valve c22, the first branch and the second branch are connected in parallel, and 2 branch pipelines are disposed behind a valve c 22;

the first branch comprises a pressure regulating valve c41, a sensor e51, a valve c62 and a throttling device c72, a sensor e51 for measuring pressure behind the valve is installed at the downstream of the pressure regulating valve c41 for regulating medium pressure, and the throttling device c72 is connected behind the valve c 62;

the second branch comprises a pressure regulating valve d42, a sensor f52, a valve d63 and a throttling device d73, wherein a sensor f52 for measuring pressure behind the valve is installed at the downstream of the pressure regulating valve d42 for regulating medium pressure, and the throttling device d73 is connected behind the valve d 63.

The first branch and the second branch are merged into a pipeline after the throttling device c72 and the throttling device d73, the tail end of the pipeline is close to the interface of the burner 2 and is connected with a check valve c81, and the downstream of the check valve c81 is connected with the burner 2.

As shown in fig. 3, the main air path of this embodiment mainly includes multiple branches with different flow coefficients, the main air path includes an air transmission pipeline for transmitting working medium, a sensor d16 for measuring air source pressure is disposed in front of a valve d26, and a valve d26 is divided into 2 branch pipelines;

the first path comprises a pressure regulating valve e45 for regulating medium pressure, a sensor g54 for measuring pressure behind the pressure regulating valve e45 is respectively arranged at the downstream of the pressure regulating valve e45, and a throttling device e77 is connected behind the valve e 67;

the second path comprises a pressure regulating valve f46 for regulating medium pressure, a sensor h55 for measuring pressure behind the pressure regulating valve f46 is installed at the downstream of the pressure regulating valve f68, and a throttling device f78 is connected behind the valve f 68;

the first path and the second path are merged into a pipeline after the throttling device e77 and the throttling device f78, the tail end of the gas pipeline is close to the interface of the burner 2 and is connected with a check valve d85, and the downstream of the check valve d85 is connected with the burner 2.

Furthermore, the secondary natural gas circuit and the secondary air circuit are a combination of a plurality of branches with different flow coefficients, and the branches can be increased or decreased according to actual needs. The advantage of doing so is that the number of branches can be flexibly adjusted, enabling a wide range of flow regulation functions.

In another embodiment of the present invention, as shown in fig. 3, the oxygen gas line of the present invention includes a gas line for delivering working fluid, a sensor i15 for measuring the pressure of the gas source is disposed in front of a valve e25, a pressure regulating valve g44 is disposed between two switching valves consisting of a valve e25 and a valve f66, a sensor j53 for measuring the pressure after the valve g 3538 is installed downstream of the pressure regulating valve g44, a throttling device g76 is connected behind the valve f66, a check valve e84 is connected at the end of the gas line near the interface of the burner 2, and a check valve e84 is connected with the main air line through a tee joint.

Furthermore, the oxygen path and the air main path are connected before entering the combustor 2, so that the mixing process is prolonged, the mixing is more uniform, and the combustion efficiency is improved.

In another embodiment of the present invention, as shown in fig. 3, the air cooling circuit of the present invention includes an air pipe for delivering working medium, a sensor k13 for measuring the pressure of the air source is disposed in front of a valve f23, a pressure regulating valve h43 is disposed between two switching valves consisting of a valve f23 and a valve g64, a sensor l56 for measuring the pressure after the valve is installed downstream of the pressure regulating valve h43, a throttling device h74 is connected behind the valve g64, the air pipe is directly connected to the inlet of the cooling channel of the combustor 2, the outlet of the cooling channel of the combustor 2 is connected to a switching valve a69 through a pipeline, and the switching valve a69 is discharged to the outside through a pipeline.

On the basis of the embodiment 1, as shown in fig. 3, in another embodiment of the present invention, the air cooling path of the present invention is divided into two paths at the outlet of the cooling channel of the burner 2 by a three-way pipe, and one path is connected with a valve c92 to open to the outside; the other path is connected between the air main path check valve d85 and the burner 2 after passing through a check valve b 91. The air cooling circuit can provide a large flow of air for cooling the burner again by the above structure. The air conditioner has the advantages that large-flow air is provided for the air main path, the air of the air cooling path is recycled, and energy is saved; effectively reduces the air main path branches, simplifies the structure, improves the system reliability and reduces the cost.

On the basis of the above embodiment, as shown in fig. 1, a control device of a heat storage heater for a wind tunnel experiment is used in the preheating stage of a heat storage type pure air wind tunnel, and the heat storage heater control system includes a working medium supply system 1 (shown in fig. 1), a burner 2, a heat storage body 3, a heat storage temperature detection system 4, a cold air intake valve 5, a smoke exhaust system 6, a pollution discharge system 7, a flame detector 8 for detecting the main flame of the burner 2, and a computer control system based on a PLC.

Heat accumulation body 3 vertically lay on the regenerator well support frame, hold hot combustor 2 and install at heat accumulation body top through flange joint, working medium supply system 1 is located 2 not distant places of combustor, various air feed sweetgum fruits are through high temperature hose and 2 interface connections of combustor.

In the heat storage temperature detection system 4, the central line of the heat storage body is a cylindrical axis, and the heat storage body consists of a plurality of thermocouples which are arranged in a circular scattering manner from inside to outside and from bottom to top (as shown in figure 1), and the thermocouples are connected to a remote acquisition module of the PLC control system through thermocouple compensation wires and through adapter flanges.

The opening of the lower end of the heat storage body is connected with a temperature-resistant stainless steel pipeline through a flange, the cold air inlet valve 5 and the smoke exhaust valve system 6 are arranged at 90 degrees and are connected with the cold air inlet valve 5 and the smoke exhaust valve system through a tee joint, the cold air inlet valve 5 is close to the opening of the heat storage body, and the distance between the interface of the smoke exhaust system 6 and the interface of the cold air inlet valve 5 is about 0.5 m. The tail end of the temperature-resistant stainless steel pipeline is vertically connected with a sewage system 7.

The smoke exhaust system comprises a smoke exhaust valve 601 connected with a temperature-resistant stainless steel pipeline, a fan 602 is connected at the downstream, and a normal-pressure smoke exhaust pipeline connected at the downstream of the fan 602 is communicated with outdoor atmosphere. The smoke exhaust system further comprises a differential pressure sensor 603 installed on the heat storage body, and the range is 0-40 bar. One end of a measuring head of the differential pressure sensor 603 is positioned at the position of the heat accumulation body close to the gas burner, and the other end of the measuring head is positioned at the joint of the heat accumulation body and the stainless steel pipe. During heat storage, the negative pressure environment of the heat storage body is smoothly established; during the wind tunnel test, avoided cold air directly to discharge from smoke exhaust system, the wind tunnel test failure that can't build pressure and lead to.

Fig. 4 is a graph of heating data from a single test of the present invention, showing that the temperature rise during heating is smooth and continuous. The function of stepless regulation of flow in the measuring range is realized. The accurate measurement and control of typical working conditions and the ability of reheating after the wind tunnel test are realized, and the test efficiency is greatly improved. The invention has clear principle, simple structure, easy realization and extremely high application value.

The above description is not meant to be limiting, it being noted that: it will be apparent to those skilled in the art that various changes, modifications, additions and substitutions can be made without departing from the true scope of the invention, and these improvements and modifications should also be construed as within the scope of the invention.

Claims

1. A measurement and control method of a heat accumulation heater for a wind tunnel experiment is characterized by being applied to a preheating stage of a heat accumulation type pure air wind tunnel and comprising a working medium supply system, wherein a stop valve is respectively arranged at the front and the rear of each pressure regulating valve of the working medium supply system, and the stop valves are respectively a valve and a two valve; the method specifically comprises the following steps:

s00: beginning: the test enters an automatic operation stage;

s10: opening a smoke exhaust system and a blowdown system, closing a cold air inlet valve, and sequentially opening one valve of each branch of an empty point way, a natural gas main way and an air main way of a working medium supply system and one valve of each way of an oxygen supplementing way;

s20: sequentially opening an empty point path valve and a natural gas path valve, and judging whether the respective pressures reach preset pressures;

s80: sequentially zeroing pressure regulating valves of all branches of the natural gas main path, the oxygen supplementing path and all branches of the air main path, sequentially closing two valves and one valve of all branches, a smoke exhaust system and a blowdown system, and opening a cold air inlet valve;

2. The measurement and control method of the heat storage heater for the wind tunnel experiment according to claim 1, wherein the working medium supply system comprises a natural gas point path, an air point path, a natural gas main path, an air main path, an oxygen supplementing path, a cooling air path, a pressure sensor and a flame detector;

the front and the back of each pressure regulating valve of the natural gas point way, the air point way, the natural gas main way, the air main way, the oxygen supplementing way and the cooling air way are respectively provided with a stop valve which is a valve and a two valve;

the natural gas main path, the air main path and the oxygen supplementing path are respectively connected with the main burner, the wide-range flow is regulated through the natural gas main path and the air main path, and oxygen input is provided for the ultra-high temperature working condition of the heat storage heater through the oxygen supplementing path;

3. The measurement and control method of the heat storage heater for the wind tunnel experiment as claimed in claim 2, wherein the natural gas point path and the air point path are the same in structure and comprise a gas transmission pipeline, a sensor, a pressure reducing valve, a throttling device and a check valve, and the cooling air pipeline is connected with a cooling channel of the combustor; the sensor is arranged in front of the first valve of the pipeline, and the pressure of the air source is measured by the sensor; the pressure reducing valve is arranged between a valve and a two valve, the rear end of the two valves is connected with a throttling device, the tail end of the gas transmission pipeline close to the burner interface is connected with a check valve, and the downstream of the check valve is connected with an igniter of the burner; the natural gas main path and the air main path comprise a plurality of branches with different flow coefficients, and the branches are increased or decreased according to actual needs; each branch is provided with a regulating valve and is synchronously opened, the regulating valve and a downstream pressure sensor form a closed-loop control loop, and the regulating valve is adjusted in real time according to parameters given by the measurement and control system.

4. The method for measuring and controlling the heat storage heater for the wind tunnel experiment as claimed in claim 1, wherein the step S20 is set as an igniter air supply process, an idle point valve is firstly opened, a control system judges whether a preset value P1 is reached according to a pressure signal of the control system, and the operation is directly interrupted if the preset value is not reached; otherwise, the natural gas point-path valve is continuously opened, the measurement and control system judges whether the natural gas point-path reaches a preset value P2 according to the pressure signal, if the pressure signal does not reach the preset value, the operation is directly interrupted, and if the pressure signal does not reach the preset value, the step S30 is executed.

5. The method as claimed in claim 1, wherein the step S30 is performed by powering on a spark plug, the measurement and control system determines whether the ignition is successful according to a pressure signal P3, if so, the step S40 is performed, otherwise, the step S50 is performed.

6. The method according to claim 1, wherein the step S40 is configured as a main flame working process of the burner, and the method comprises the steps of opening valves of each branch of the main air passage and each branch of the natural gas passage in sequence, synchronously opening each branch of the main air passage and the natural gas passage regulating valve according to preset parameters given by the measurement and control system, and respectively judging whether the respective pressure reaches a preset value; the flame detector detects whether the heater is normally combusted intermittently, and the working time interval of the flame detector is t 5; if the detector does not alarm, continuing to S80; if the detector alarms, proceed directly to S50.

7. The method for measuring and controlling the heat storage heater for the wind tunnel experiment as claimed in claim 1, wherein the step S50 is that the measurement and control system directly reverses to the step S30 to determine whether the pressure of the igniter reaches the preset value P3, if the preset value is met, the system is kept without operation within the time t6, and waits until the alarm of the flame detector disappears, otherwise, the method goes to the step S80 and goes to the step of stopping; if no more alarm is given, the process proceeds to step S70.

8. The method for measuring and controlling the heat storage heater for the wind tunnel experiment as claimed in claim 1, wherein the step S60 is an operation step taken when the pressure of the igniter is lower than a preset value after the heat storage burner normally works, the pressure regulating valves of the natural gas main path and the air main path are sequentially set to 0, the natural gas point valve is closed, the step S20 of opening the natural gas path valve is re-entered, the time limit for restarting the igniter is t7, and if the time limit is over, the igniter fails to restart, and the step S80 of stopping is directly entered.

9. The method for measuring and controlling the regenerative heater for the wind tunnel experiment according to claim 1, wherein the step S00 is a test starting step, the step S70 is set as a working condition adjusting stage of the regenerative burner, and the step S70 selects any one of a full manual mode, a semi-automatic mode or a full automatic mode according to the step S00; when the valves are opened or closed in sequence, the interval time is set as t1, each valve or actuating mechanism is transmitted to the measurement and control system through a feedback signal, and the signal is not used as the judgment basis for program execution.

10. The measurement and control method of the heat storage heater for the wind tunnel experiment according to claim 1, which adopts a measurement and control device of the heat storage heater for the wind tunnel experiment, and is characterized in that the control device comprises a working medium supply system, a burner, a heat storage body, a heat storage temperature detection system, a cold air inlet valve, a smoke exhaust system and a sewage discharge system, wherein the heat storage body is vertically arranged on a heat storage well supporting frame, the burner is arranged at the top of the heat storage body through flange connection, and each branch air supply channel of the working medium supply system is connected with a burner interface through a high-temperature hose; the heat storage temperature detection system is arranged in the heat storage body and is used for detecting the temperature; the cold air inlet valve, the smoke exhaust system and the sewage discharge system are arranged at the lower part of the heat storage body.