Explosion-proof fresh air system of hydrogen-related environment chamber and control method of explosion-proof fresh air system

Abstract

The invention relates to the field of environmental simulation testing, and particularly discloses an anti-explosion fresh air system of a hydrogen-related environmental chamber and a control method of the anti-explosion fresh air system. One end of the normal-temperature fresh air pipeline is communicated with the end part of the fresh air sampling pipeline, and the other end of the normal-temperature fresh air pipeline is connected with the second stop valve; one end of the fresh air inlet pipeline is connected to the second stop valve, the other end of the fresh air inlet pipeline is connected to a fresh air fan through a pipeline, and the fresh air inlet pipeline is provided with a first stop valve; one end of the high-low temperature fresh air pipeline is connected to the pipeline on one side, far away from the test engine sample, of the third stop valve, and the other end of the high-low temperature fresh air pipeline is connected to the pipeline between the fresh air fan and the second stop valve; the high-low temperature fresh air pipeline is sequentially provided with a fourth stop valve, a dehumidifier and a heat exchanger in the fresh air flowing direction. According to the anti-explosion fresh air system and the control method thereof, the problems that hydrogen flows backwards, energy is wasted and the temperature is unstable in a traditional hydrogen-related environment chamber with a fresh air function are solved.

Description

Technical Field

[0001] The present invention relates to the field of environmental simulation testing, and particularly to an explosion-proof fresh air system for a hydrogen-related environmental chamber and a control method thereof. Background Art

[0002] Currently, a hydrogen-related environmental chamber provides a controllable environment, enabling researchers to deeply study the performance and safety of hydrogen-using devices under different environmental conditions. It is usually composed of a sealed container, and various environmental conditions such as temperature, pressure, humidity, etc. can be simulated inside the container to evaluate the performance and safety of hydrogen-using devices. At the same time, the risk brought by hydrogen leakage inside the container needs to be solved. With the rapid development of the hydrogen energy industry, the current demand for hydrogen-related environmental testing has increased extremely rapidly.

[0003] In the related art, for a traditional hydrogen-related environmental chamber with a fresh air function, a fresh air unit conveys air (i.e., fresh air) to the environmental chamber through an external pipeline penetrating the side wall of the environmental chamber, and the test engine sample extracts the fresh air inside the chamber for operation and testing.

[0004] The traditional hydrogen-related environmental chamber has many defects in terms of the fresh air function:

[0005] ① In a traditional hydrogen-related environmental chamber with a fresh air function, the fresh air directly enters the interior of the environmental chamber and is connected to the temperature control system and the gas circulation system inside the chamber. When hydrogen leaks inside the chamber, there is a risk that hydrogen gas inside the environmental chamber will backflow into the fresh air system, causing safety hazards.

[0006] ② The fresh air system of a traditional hydrogen-related environmental chamber with a fresh air function has only one pipeline and the control mode adopts a pressure balance scheme. To ensure sufficient fresh air inside the chamber, an over-supply method is mostly used, which cannot accurately match the actual fresh air demand of the test sample, resulting in waste of energy.

[0007] ③ A traditional hydrogen-related environmental chamber with a fresh air function cannot pre-cool / pre-heat the gas inside the fresh air system pipeline, and it is mostly natural wind, resulting in unstable fresh air temperature entering the test sample and unable to meet the test requirements. Summary of the Invention

[0008] The present application provides an explosion-proof fresh air system for a hydrogen-related environmental chamber and a control method thereof, which solve the problems of hydrogen backflow, energy waste, and unstable temperature in a traditional hydrogen-related environmental chamber with a fresh air function.

[0009] In a first aspect, an embodiment of the present application provides an explosion-proof fresh air system for a hydrogen-related environmental chamber, comprising:

[0010] A fresh air sampling pipeline, which penetrates the side wall of the environmental chamber and is connected to the air inlet of the test engine sample arranged inside the environmental chamber; a third stop valve is arranged on the fresh air sampling pipeline.

[0011] The normal-temperature fresh air pipeline has one end connected to the end of the fresh air sampling pipeline and the other end connected to the second stop valve.

[0012] The fresh air inlet pipeline has one end connected to the second stop valve and the other end connected to the fresh air fan through a pipeline. The first stop valve is provided on the fresh air inlet pipeline.

[0013] The high-low temperature fresh air pipeline has one end connected to the pipeline on the side of the third stop valve away from the test engine sample, and the other end connected to the pipeline between the fresh air fan and the second stop valve. The fourth stop valve, the dehumidifier, and the heat exchanger are sequentially arranged on the high-low temperature fresh air pipeline in the fresh air flow direction.

[0014] Combined with the first aspect, in an embodiment, the explosion-proof fresh air system further includes a controller. The controller is signal-connected to the fresh air fan, the heat exchanger, and all stop valves, and the controller obtains the operating power of the test engine sample in real time. The fresh air sampling pipeline is provided with a fresh air sampling pressure sensor and a fresh air sampling flow sensor.

[0015] The controller is used to pre-load the fresh air volume of the fresh air fan according to the operating power of the test engine sample, and feedback and adjust the air intake volume of the fresh air fan according to the pressure value obtained from the fresh air sampling pressure sensor and the flow value obtained from the fresh air sampling flow sensor.

[0016] Combined with the first aspect, in an embodiment, the fresh air sampling pipeline is further provided with a fresh air sampling temperature sensor. The high-low temperature fresh air pipeline is further provided with a high-low temperature fresh air pipeline temperature sensor and a high-low temperature fresh air pipeline flow sensor. The controller is used to dynamically control the heat exchange power of the heat exchanger according to the temperature difference signal between the fresh air sampling temperature sensor and the high-low temperature fresh air pipeline temperature sensor, and the flow signal of the high-low temperature fresh air pipeline flow sensor.

[0017] Combined with the first aspect, in an embodiment, the explosion-proof fresh air system further includes a fresh air internal circulation pipeline. One end of the fresh air internal circulation pipeline is connected to the pipeline between the first stop valve and the fresh air fan, and the other end is communicated with the pipeline on the side of the third stop valve away from the test engine sample. The fifth stop valve is provided on the fresh air internal circulation pipeline.

[0018] Combined with the first aspect, in an embodiment, the explosion-proof fresh air system further includes a purging and discharging pipeline. One end of the purging and discharging pipeline is communicated between the fifth stop valve and the fresh air sampling pipeline, and the other end is open to the outside. The sixth stop valve is provided on the purging and discharging pipeline.

[0019] When a failure occurs in the test engine sample or other situations where it is necessary to relieve pressure and purge the normal-temperature / high-low temperature fresh air pipeline, the sixth stop valve is opened to relieve pressure and purge the fresh air pipeline.

[0020] In combination with the first aspect, in one embodiment, in the fresh air inlet pipeline, the side of the first stop valve away from the fresh air fan is connected to the air filter through a pipeline.

[0021] In the second aspect, the present application discloses a control method based on the above explosion-proof fresh air system, and the control method includes a normal temperature fresh air supply mode and a high and low temperature fresh air supply mode;

[0022] The normal temperature fresh air supply mode includes the following steps:

[0023] Close the fourth stop valve, and open the first stop valve, the second stop valve, and the third stop valve;

[0024] Start the fresh air fan, the fresh air inlet pipeline sucks in fresh air, and the fresh air is transported to the test engine sample through the normal temperature fresh air pipeline and the fresh air sampling pipeline;

[0025] The high and low temperature fresh air supply mode includes the following steps:

[0026] Close the second stop valve, and open the first stop valve, the third stop valve, and the fourth stop valve;

[0027] Start the fresh air fan, the fresh air enters the high and low temperature fresh air pipeline through the fresh air inlet pipeline, and after being dehumidified by the dehumidifier and heat-exchanged by the heat exchanger in the high and low temperature fresh air pipeline, it enters the test engine sample through the fresh air sampling pipeline.

[0028] In combination with the second aspect, in one embodiment, the fresh air sampling pipeline is provided with a fresh air sampling temperature sensor, a fresh air sampling pressure sensor, and a fresh air sampling flow sensor; the high and low temperature fresh air pipeline is provided with a high and low temperature fresh air pipeline temperature sensor, a high and low temperature fresh air pipeline pressure sensor, and a high and low temperature fresh air pipeline flow sensor; the explosion-proof fresh air system further includes a controller, the controller is signal-connected to the fresh air fan, the heat exchanger, all stop valves, and all sensors, and the controller obtains the operating power of the test engine sample in real time;

[0029] In the normal temperature fresh air supply mode, the controller pre-loads the operating power of the fresh air fan according to the operating power of the test engine sample, and feedback-adjusts the operating power of the fresh air fan according to the pressure value obtained from the fresh air sampling pressure sensor and the flow value obtained from the fresh air sampling flow sensor.

[0030] In combination with the second aspect, in one embodiment, the high and low temperature fresh air supply mode further includes:

[0031] When initially starting the fresh air fan, the controller is used to pre-load the operating power of the fresh air fan according to the operating power of the test engine sample;

[0032] After the fresh air fan is started for a period of time, the controller feedback-adjusts the operating power of the fresh air fan according to the pressure value obtained from the fresh air inlet pressure sensor and the flow value obtained from the fresh air inlet flow sensor; at the same time, the controller is used to dynamically regulate the heat exchange power of the heat exchanger according to the temperature difference signal of the fresh air inlet temperature sensor and the high and low temperature fresh air pipeline temperature sensor, as well as the flow signal of the high and low temperature fresh air pipeline flow sensor.

[0033] Combined with the second aspect, in an embodiment, the explosion-proof fresh air system further includes a fresh air internal circulation pipeline. One end of the fresh air internal circulation pipeline is connected to the pipeline between the first stop valve and the fresh air fan, and the other end communicates with the pipeline on the side of the third stop valve away from the tested engine sample. A fifth stop valve is provided on the fresh air internal circulation pipeline; the explosion-proof fresh air system further includes a purging and discharging pipeline. One end of the purging and discharging pipeline communicates between the fifth stop valve and the fresh air inlet pipeline, and the other end is open to the outside; a sixth stop valve is provided on the purging and discharging pipeline;

[0034] Before entering the high and low temperature fresh air supply mode, it further includes a precooling / preheating mode, and the precooling / preheating mode includes the steps:

[0035] Open the fourth stop valve and the fifth stop valve, and close the first stop valve, the second stop valve, the third stop valve and the sixth stop valve;

[0036] Start the fresh air fan, and the gas remaining in the pipeline enters the high and low temperature fresh air pipeline through the fresh air internal circulation pipeline after circulating through the fresh air fan for primary dehumidification and precooling / preheating, and then enters the fresh air internal circulation pipeline again after circulating through the fresh air fan and enters the high and low temperature fresh air pipeline for secondary dehumidification and precooling / preheating. Repeat this process until the gas remaining in the pipeline reaches the temperature value set by the fresh air inlet temperature sensor.

[0037] The beneficial effects brought by the technical solution provided by the embodiment of the present application at least include:

[0038] 1. The explosion-proof fresh air system of the present application has a fresh air inlet pipeline running through the side wall of the environmental chamber and directly connected to the air inlet of the test engine sample arranged inside the environmental chamber. Compared with the situation in the traditional technical solution where fresh air mixes with the gas inside the environmental chamber, the explosion-proof fresh air system of the present application adopts a sealed fresh air pipeline. All fresh air paths adopt a pipeline structure and are not connected to the gas system inside the hydrogen-related environmental chamber. After the fresh air enters the environmental chamber, it is directly connected to the air inlet of the test sample through a sealed pipeline, effectively solving the risk of hydrogen backflow into the fresh air system after hydrogen leakage. At the same time, the explosion-proof fresh air system adopts a parallel mode of a normal-temperature fresh air pipeline and a high-low temperature fresh air pipeline. The high-low temperature fresh air pipeline is provided with a dehumidifier and a heat exchanger, which can heat the flowing fresh air. By reasonably selecting the required pipeline, the explosion-proof fresh air system meets the requirements of the test engine sample for different environmental temperature tests. In addition, the high-low temperature fresh air pipeline uses a heat exchanger to control the temperature of the fresh air. The fresh air does not directly contact the heater or cooler, improving the safety of the fresh air temperature control system.

[0039] 2. For the explosion-proof fresh air system of the present application, when the fresh air volume of the fresh air fan starts to run, the controller pre-loads according to the operating power of the test engine sample. After that, according to the pressure value obtained from the fresh air inlet pressure sensor and the flow value obtained from the fresh air inlet flow sensor, the operating power of the fresh air fan is coupled and controlled to negatively feedback adjust the fresh air intake volume, forming a closed-loop control. On the premise of ensuring the energy saving of the fresh air system, the operating power is stabilized, that is, the fresh air volume is stable, and the operating power demand of the test engine sample is maximally met with the minimum energy consumption, solving the problem of energy waste caused by over-supply in the hydrogen-related environmental chamber with the traditional fresh air function.

[0040] 3. For the explosion-proof fresh air system of the present application, the controller automatically calculates the cumulative heat exchange required for the fresh air volume passing through within a certain period of time to reach the set temperature according to the temperature difference signal of the fresh air inlet temperature sensor and the high-low temperature fresh air pipeline temperature sensor, the flow signal of the high-low temperature fresh air pipeline flow sensor, and the set temperature target value, and dynamically regulates the heat exchange power of the heat exchanger. By dynamically controlling the heat exchange power of the heat exchanger, the energy saving of fresh air temperature control is achieved. The fresh air control system ensures the stability of the fresh air volume and temperature of the fresh air system on the premise of ensuring the energy saving of the fresh air system, and maximally meets the operating power and fresh air temperature requirements of the test engine sample with the minimum energy consumption.

[0041] 4. The explosion-proof fresh air system of the present application is provided with a fresh air internal circulation pipeline in parallel with the high and low temperature fresh air pipelines, effectively solving the problem that the traditional hydrogen-related environment chamber cannot pre-cool / pre-heat fresh air. Before the explosion-proof fresh air system actually operates, the first cut-off valve, the second cut-off valve, and the third cut-off valve can be closed, the fourth cut-off valve and the fifth cut-off valve can be opened, the high and low temperature fresh air pipelines and the fresh air internal circulation pipeline can be opened, other pipelines can be closed, the fresh air fan and the heat exchanger can be started, and the gas in the high and low temperature fresh air pipelines can be pre-cooled / pre-heated by internal circulation to ensure the stability of the fresh air temperature entering the sample subsequently.

[0042] 5. The control method of the explosion-proof fresh air system of the present application. When the fresh air volume of the fresh air fan starts to operate, the controller pre-loads according to the operating power of the tested engine sample. After that, according to the pressure value obtained from the fresh air inlet pressure sensor and the flow value obtained from the fresh air inlet flow sensor, the operating power of the fresh air fan is coupled and controlled to negatively feedback and adjust the fresh air intake volume, forming a closed-loop control. On the premise of ensuring the energy saving of the fresh air system, the operating power is stabilized, and the operating power demand of the tested engine sample is met to the greatest extent with the minimum energy consumption, reducing the power consumption of the fresh air system and achieving energy saving for normal temperature fresh air. It solves the problem of energy waste caused by excessive energy supply in the traditional hydrogen-related environment chamber with fresh air function. BRIEF DESCRIPTION OF THE DRAWINGS

[0043] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the following will briefly introduce the drawings required for the description of the embodiments. Obviously, the following drawings are only some embodiments of the present application. For those of ordinary skill in the art, without creative efforts, other drawings can be obtained based on these drawings.

[0044] Figure 1 It is a flow block diagram of the explosion-proof fresh air system provided by the embodiment of the present application;

[0045] In the figure: 1, air filter; 2, fresh air fan; 3, dehumidifier; 4, heat exchanger; 5, environmental chamber; 6, tested engine sample;

[0046] 101, first cut-off valve; 102, second cut-off valve; 103, third cut-off valve; 104, fourth cut-off valve; 105, fifth cut-off valve; 106, sixth cut-off valve;

[0047] 11, fresh air inlet pipeline; 12, normal temperature fresh air pipeline; 13, fresh air inlet sampling pipeline; 14, high and low temperature fresh air pipeline; 15, fresh air internal circulation pipeline; 16, purge and relief pipeline;

[0048] 21, fresh air inlet sampling temperature sensor; 22, fresh air inlet sampling pressure sensor; 23, fresh air inlet sampling flow sensor;

[0049] 31. High and low temperature fresh air pipeline temperature sensor; 32. High and low temperature fresh air pipeline pressure sensor; 33. High and low temperature fresh air pipeline flow sensor. Detailed implementation manners

[0050] In order to enable those skilled in the art to better understand the solutions of this application, the technical solutions in the embodiments of this application will be clearly and completely described below in conjunction with the accompanying drawings in the embodiments of this application. Obviously, the described embodiments are only a part of the embodiments of this application, rather than all the embodiments. Based on the embodiments in this application, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of this application.

[0051] In a traditional hydrogen-related environment chamber with fresh air function, under normal test conditions, hydrogen in the chamber is stored in a separate hydrogen cylinder, and there is no hydrogen in the chamber environment. However, hydrogen is extremely easy to leak, and once leaked, the chamber will be filled with hydrogen. When fresh air mixes with the gas in the environment chamber 5, hydrogen will also be mixed in, resulting in hydrogen backflow.

[0052] In view of this, in order to ensure the safety of the hydrogen-related environment chamber after hydrogen leakage, this application provides an explosion-proof fresh air system for a hydrogen-related environment chamber and its control method, which solves the problems of hydrogen backflow, energy waste and unstable temperature in traditional hydrogen-related environment chambers with fresh air function, and can prevent hydrogen backflow, maximize the use of energy, and have stable temperature control.

[0053] As Figure 1 shown, this application discloses an embodiment of an explosion-proof fresh air system for a hydrogen-related environment chamber. The environment chamber 5 is used to accommodate the test engine sample 6. The test engine sample 6 obtains hydrogen from the hydrogen supply system and fresh air from the explosion-proof fresh air system to perform work.

[0054] The explosion-proof fresh air system includes a fresh air sampling pipeline 13, a normal temperature fresh air pipeline 12, a fresh air inlet pipeline 11 and a high and low temperature fresh air pipeline 14.

[0055] Among them, the fresh air sampling pipeline 13 penetrates the side wall of the environment chamber 5 and is connected to the air inlet of the test engine sample 6 arranged in the environment chamber 5 to directly supply air to the test engine sample 6. Compared with the situation where fresh air mixes with the gas in the environment chamber 5 in the traditional technical solution, the fresh air of the explosion-proof fresh air system in this application does not mix with the environment chamber 5 before entering the test engine sample 6. The fresh air sampling pipeline 13 is directly connected to the air inlet of the test engine sample 6 arranged in the environment chamber 5, effectively preventing hydrogen backflow caused by hydrogen leakage. A third stop valve 103 is provided on the fresh air sampling pipeline 13, and the third stop valve 103 controls the on-off of the fresh air sampling pipeline 13.

[0056] One end of the normal temperature fresh air pipeline 12 communicates with the end of the fresh air sampling pipeline 13, and the other end is connected to the second stop valve 102. One end of the fresh air inlet pipeline 11 is connected to the second stop valve 102, and the other end is connected to the fresh air fan 2 through a pipeline. The fresh air inlet pipeline 11 is provided with a first stop valve 101. Under normal conditions, fresh air enters the fresh air inlet pipeline 11 through the fresh air fan 2, and passes through the normal temperature fresh air pipeline 12 and the fresh air sampling pipeline 13 all the way to enter the air inlet of the test engine sample 6, completing the supply of fresh air to the test engine sample 6.

[0057] One end of the high and low temperature fresh air pipeline 14 is connected to the pipeline on the side of the third stop valve 103 away from the test engine sample 6, and the other end is connected to the pipeline between the fresh air fan 2 and the second stop valve 102; the high and low temperature fresh air pipeline 14 is sequentially provided with a fourth stop valve 104, a dehumidifier 3 and a heat exchanger 4 in the fresh air flow direction.

[0058] In the explosion-proof fresh air system of the present application, the fresh air sampling pipeline 13 penetrates the side wall of the environmental chamber 5 and is directly connected to the air inlet of the test engine sample 6 arranged in the environmental chamber 5. Compared with the situation where fresh air is mixed with the gas in the environmental chamber 5 in the traditional technical solution, the fresh air of the explosion-proof fresh air system of the present application does not mix with the environmental chamber 5 before entering the test engine sample 6, effectively solving the risk of hydrogen backflow caused by hydrogen leakage;

[0059] At the same time, the explosion-proof fresh air system adopts a parallel connection mode of the normal temperature fresh air pipeline 12 and the high and low temperature fresh air pipeline 14. The high and low temperature fresh air pipeline 14 is provided with a dehumidifier 3 and a heat exchanger 4, which can heat the flowing fresh air, and reasonably select the required pipeline. The explosion-proof fresh air system meets the requirements of the test engine sample 6 for testing at different environmental temperatures;

[0060] In addition, the high and low temperature fresh air pipeline 14 uses a heat exchanger 4 to control the temperature of the fresh air. The fresh air does not directly contact the heater or the cooler, improving the safety of the fresh air temperature control system.

[0061] Specifically, all stop valves can be opened and closed manually, or can be opened and closed by a signal through the controller.

[0062] In one embodiment, the explosion-proof fresh air system further includes a controller, and the controller is signal-connected to the fresh air fan 2, the heat exchanger 4 and all stop valves. The controller can control the operating power of the fresh air fan 2, control the heat exchange power of the heat exchanger 4, and can also control the opening and closing of all stop valves.

[0063] The controller obtains the operating power of the test engine sample 6 in real time. The fresh air inlet pipeline 13 is provided with a fresh air inlet pressure sensor 22 and a fresh air inlet flow sensor 23, and the fresh air inlet pressure sensor 22 and the fresh air inlet flow sensor 23 are respectively connected to the controller by signals. The controller obtains the pressure value and the flow value of the fresh air inlet pipe 13.

[0064] The controller preloads the fresh air volume of the fresh air fan 2 according to the operating power of the test engine sample 6, and feedback-adjusts the air intake volume of the fresh air fan 2 according to the pressure value obtained from the fresh air inlet pressure sensor 22 and the flow value obtained from the fresh air inlet flow sensor 23.

[0065] The fresh air volume of the fresh air fan 2 is positively correlated with the operating power of the fresh air fan 2.

[0066] In the explosion-proof fresh air system of the present application, when the fresh air volume of the fresh air fan 2 starts to operate, the controller preloads according to the operating power of the test engine sample 6. After that, according to the pressure value obtained from the fresh air inlet pressure sensor 22 and the flow value obtained from the fresh air inlet flow sensor 23, the operating power of the fresh air fan 2 is coupled and controlled to negatively feedback-adjust the fresh air intake volume, forming a closed-loop control. On the premise of ensuring the energy saving of the fresh air system, the operating power is stabilized, and the operating power demand of the sample is met to the greatest extent with the minimum energy consumption, solving the problem of energy waste caused by over-supply in the traditional hydrogen-related environment chamber with fresh air function.

[0067] Specifically, initially, the corresponding relationship between the operating power of the test engine sample 6 and the fresh air volume of the fresh air fan 2 is established in a table in advance, and during actual operation, it can be directly obtained by looking up the table.

[0068] Further, on the basis of the above technical solution, the fresh air inlet pipeline 13 is further provided with a fresh air inlet temperature sensor 21, and the high and low temperature fresh air pipeline 14 is further provided with a high and low temperature fresh air pipeline temperature sensor 31 and a high and low temperature fresh air pipeline flow sensor 33. The fresh air inlet temperature sensor 21, the high and low temperature fresh air pipeline temperature sensor 31 and the high and low temperature fresh air pipeline flow sensor 33 are all connected to the controller by signals.

[0069] The controller dynamically adjusts the heat exchange power of the heat exchanger 4 according to the temperature difference signal of the fresh air inlet temperature sensor 21 and the high and low temperature fresh air pipeline temperature sensor 31, the flow signal of the high and low temperature fresh air pipeline flow sensor 33, and the set temperature target value.

[0070] For the explosion-proof fresh air system of the present application, the controller automatically calculates the cumulative heat exchange required for the fresh air volume passing through within a certain period of time to reach the set temperature according to the temperature difference signal of the fresh air inlet temperature sensor 21 and the high and low temperature fresh air pipeline temperature sensor 31, the flow signal of the high and low temperature fresh air pipeline flow sensor 33, and the set temperature target value, and dynamically regulates the heat exchange power of the heat exchanger 4. By dynamically controlling the heat exchange power of the heat exchanger 4, energy conservation for fresh air temperature control is achieved. The fresh air control system ensures the stability of the air volume and temperature of the fresh air system while guaranteeing the energy conservation of the fresh air system, and meets the requirements of the operating power of the sample and the fresh air temperature with the minimum energy consumption to the greatest extent.

[0071] In one embodiment, the explosion-proof fresh air system further includes a fresh air internal circulation pipeline 15. One end of the fresh air internal circulation pipeline 15 is connected to the pipeline between the first stop valve 101 and the fresh air fan 2, and the other end communicates with the pipeline on the side of the third stop valve 103 away from the test engine sample 6. A fifth stop valve 105 is provided on the fresh air internal circulation pipeline 15.

[0072] For the explosion-proof fresh air system of the present application, a fresh air internal circulation pipeline 15 is provided in parallel with the high and low temperature fresh air pipeline 14, effectively solving the problem that the traditional hydrogen-containing environment chamber cannot pre-cool / pre-heat fresh air. Before the actual operation of the explosion-proof fresh air system, the first stop valve 101, the second stop valve 102, and the third stop valve 103 can be closed, the fourth stop valve 104 and the fifth stop valve 105 can be opened, the high and low temperature fresh air pipeline and the fresh air internal circulation pipeline can be opened, other pipelines can be closed, the fresh air fan and the heat exchanger can be started, and the gas in the high and low temperature fresh air pipeline can be pre-cooled / pre-heated by internal circulation to ensure the stability of the fresh air temperature entering the sample subsequently.

[0073] Furthermore, the explosion-proof fresh air system further includes a purge and vent pipeline 16. One end of the purge and vent pipeline 16 communicates between the fifth stop valve 105 and the fresh air inlet pipeline 13, and the other end is open to the outside; a sixth stop valve 106 is provided on the purge and vent pipeline 16.

[0074] When the test engine sample 6 fails or other situations require pressure relief and purging of the normal temperature / high and low temperature fresh air pipeline, the sixth stop valve 106 is opened for pressure relief and purging of the fresh air pipeline. At the same time, the operating power of the fresh air fan 2 and the heat exchange power of the heat exchanger 4 are automatically reduced to reduce the fresh air volume and heat exchange amount, timely reducing the energy consumption of the explosion-proof fresh air system and improving the safety of the explosion-proof fresh air system.

[0075] Preferably, the sixth stop valve 106 is also signal-connected to the controller, and the controller controls the opening or closing of the sixth stop valve 106 to achieve pressure relief and purging.

[0076] Specifically, when a failure occurs in the test engine sample 6, it can be determined that the test engine sample has failed when the controller detects that the difference between the flow rate obtained by the fresh air inlet flow sensor and the required fresh air volume of the current fresh air fan pre-loaded with the test condition is large, or when the flow rate obtained by the fresh air inlet flow sensor quickly drops to 0.

[0077] Further, in the fresh air inlet pipeline 11, an air filter 1 is connected and arranged on the side of the first cut-off valve 101 away from the fresh air fan 2. After the fresh air is filtered, it is then sucked into the pipeline by the fresh air fan 2.

[0078] Preferably, the fresh air inlet temperature sensor 21 and the fresh air inlet pressure sensor 22 are set between the connection points of the normal temperature fresh air pipeline 12 and the high and low temperature fresh air pipeline 14 close to the test engine sample 6, and between the connection points of the normal temperature fresh air pipeline 12 and the fresh air internal circulation pipeline 15 close to the test engine sample 6.

[0079] Further, the position where the fresh air inlet pipeline 13 communicates with the air inlet of the test engine sample 6 is sealed by a sealing ring. All fresh air ducts adopt a pipeline structure and are not connected to the hydrogen-containing environment chamber. After the fresh air enters the environment chamber, it is sealed by a sealing ring at the interface position of the air inlet of the test engine sample 6 and is not connected to the hydrogen-containing environment chamber, which can effectively prevent the hydrogen-containing gas in the hydrogen-containing environment chamber from flowing back into the fresh air system and achieve the safety and explosion protection of the fresh air system.

[0080] In the second aspect, the present application discloses an embodiment of a control method based on the above explosion-proof fresh air system. The control method includes a normal temperature fresh air supply mode, and the normal temperature fresh air supply mode includes the following steps:

[0081] Close the fourth cut-off valve 104, and open the first cut-off valve 101, the second cut-off valve 102, and the third cut-off valve 103;

[0082] Start the fresh air fan 2, the fresh air inlet pipeline 11 sucks fresh air, and the fresh air is transported to the test engine sample 6 through the normal temperature fresh air pipeline 12 and the fresh air inlet pipeline 13.

[0083] The control method includes a high and low temperature fresh air supply mode, and the high and low temperature fresh air supply mode includes the following steps:

[0084] Close the second cut-off valve 102, and open the first cut-off valve 101, the third cut-off valve 103, and the fourth cut-off valve 104;

[0085] Start the fresh air fan 2, the fresh air enters the high and low temperature fresh air pipeline 14 through the fresh air inlet pipeline 11, and after being dehumidified by the dehumidifier 3 and heat-exchanged by the heat exchanger 4 in the high and low temperature fresh air pipeline 14, it enters the test engine sample 6 through the fresh air inlet pipeline 13.

[0086] Regarding the control method, in one embodiment, a fresh air inlet pipeline 13 is provided with a fresh air inlet temperature sensor 21, a fresh air inlet pressure sensor 22, and a fresh air inlet flow sensor 23; a high and low temperature fresh air pipeline 14 is provided with a high and low temperature fresh air pipeline temperature sensor 31, a high and low temperature fresh air pipeline pressure sensor 32, and a high and low temperature fresh air pipeline flow sensor 33; the explosion-proof fresh air system further includes a controller, and the controller is signal-connected to a fresh air fan 2, a heat exchanger 4, all stop valves, and all sensors. The controller can control the operating power of the fresh air fan 2, control the heat exchange power of the heat exchanger 4, and can also control the opening and closing of all stop valves, and receive the signals of all sensors. The controller obtains the operating power of the test engine sample 6 in real time;

[0087] In the normal temperature fresh air supply mode, the controller pre-loads the operating power of the fresh air fan 2 according to the operating power of the test engine sample 6, and feedback-adjusts the operating power of the fresh air fan 2 according to the pressure value obtained from the fresh air inlet pressure sensor 22 and the flow value obtained from the fresh air inlet flow sensor 23.

[0088] For the control method of the explosion-proof fresh air system of the present application, when the fresh air volume of the fresh air fan 2 starts to operate, the controller pre-loads according to the operating power of the test engine sample 6. After that, according to the pressure value obtained from the fresh air inlet pressure sensor 22 and the flow value obtained from the fresh air inlet flow sensor 23, the controller controls the operating power of the fresh air fan 2 in a coupled manner to negatively feedback-adjust the fresh air intake volume, forming a closed-loop control. On the premise of ensuring the energy saving of the fresh air system, the operating power is stabilized, and the running power demand of the sample is maximally met with the minimum energy consumption, reducing the power consumption of the fresh air system and achieving energy saving of normal temperature fresh air. It solves the problem of energy waste caused by over-supply in the traditional hydrogen-related environment chamber with fresh air function.

[0089] Regarding the control method, in one embodiment, the high and low temperature fresh air supply mode further includes:

[0090] When initially starting the fresh air fan 2, the controller is used to pre-load the operating power of the fresh air fan 2 according to the operating power of the test engine sample 6;

[0091] After the fresh air fan 2 is started for a period of time, the controller feedback-adjusts the operating power of the fresh air fan 2 according to the pressure value obtained from the fresh air inlet pressure sensor 22 and the flow value obtained from the fresh air inlet flow sensor 23; at the same time, the controller is used to dynamically regulate the heat exchange power of the heat exchanger 4 according to the temperature difference signal between the fresh air inlet temperature sensor 21 and the high and low temperature fresh air pipeline temperature sensor 31, and the flow signal of the high and low temperature fresh air pipeline flow sensor 33.

[0092] The control method of the explosion-proof fresh air system of the present application adopts a mode of using both normal-temperature fresh air pipelines and high-low temperature fresh air pipelines. By testing the preloading control mode of the running power of the engine sample 6 and the negative feedback regulation mode of the pressure and flow coupling signal, the running power of the fresh air fan 2 is automatically adjusted, and the heat exchange amount of the fresh air system is controlled by coupling the temperature and flow signals. When the sample needs to be tested at high and low temperatures, the fresh air inlet pipeline, the high-low temperature fresh air pipeline, and the fresh air sampling pipeline are opened, and other pipelines are closed. A variable-frequency fresh air fan is used, and its fresh air volume is automatically loaded with the running power of the sample. According to the pressure and flow coupling signals fed back by the fresh air sampling pressure sensor and the fresh air sampling flow sensor set at the front end of the fresh air inlet of the sample, the running power of the fresh air fan 2 is negatively feedback adjusted, using an appropriate amount instead of the traditional excessive amount to achieve energy saving in the high-low temperature fresh air supply mode; the high-low temperature fresh air pipeline adopts a heat exchanger temperature control method, and the heat exchange power of the heat exchanger is dynamically regulated according to the signals fed back by the high-low temperature fresh air pipeline temperature and flow sensors set on the high-low temperature fresh air pipeline and the fresh air sampling temperature and flow sensors set at the front end of the fresh air inlet of the sample. By controlling the heat exchange power of the heat exchanger, energy saving in high-low temperature fresh air temperature control is achieved.

[0093] Regarding the control method, in one embodiment, the explosion-proof fresh air system further includes a fresh air internal circulation pipeline 15. One end of the fresh air internal circulation pipeline 15 is connected to the pipeline between the first cut-off valve 101 and the fresh air fan 2, and the other end communicates with the pipeline on the side of the third cut-off valve 103 far from the test engine sample 6. A fifth cut-off valve 105 is provided on the fresh air internal circulation pipeline 15; the explosion-proof fresh air system further includes a purge and discharge pipeline 16. One end of the purge and discharge pipeline 16 communicates between the fifth cut-off valve 105 and the fresh air sampling pipeline 13, and the other end is open to the outside; a sixth cut-off valve 106 is provided on the purge and discharge pipeline 16.

[0094] Before entering the high-low temperature fresh air supply mode, it further includes a precooling / preheating mode, and the precooling / preheating mode includes the steps:

[0095] Open the fourth cut-off valve 104 and the fifth cut-off valve 105, and close the first cut-off valve 101, the second cut-off valve 102, the third cut-off valve 103, and the sixth cut-off valve 106;

[0096] Start the fresh air fan 2, and the gas remaining in the pipeline passes through the fresh air internal circulation pipeline 15, circulates through the fresh air fan 2, and then enters the high-low temperature fresh air pipeline 14 for primary dehumidification and precooling / preheating. After that, it enters the fresh air internal circulation pipeline 15 again, circulates through the fresh air fan 2, and then enters the high-low temperature fresh air pipeline 14 for secondary dehumidification and precooling / preheating. Repeat this process until the gas remaining in the pipeline reaches the temperature value set by the fresh air sampling temperature sensor 21.

[0097] After reaching the target of pre-cooling / pre-heating, when starting and loading the test engine sample 6, keep the fresh air fan 2 in the open state, close the fifth shut-off valve 105, the second shut-off valve 102 and the sixth shut-off valve 106, and open the first shut-off valve 101, the fourth shut-off valve 104, and the third shut-off valve 103, then it can start to enter the high and low temperature fresh air supply mode.

[0098] Further, when the sample fails and shuts down:

[0099] Dynamically monitor the operating state of the test engine sample through the fresh air sampling flow sensor 23 provided on the fresh air sampling pipeline 13. When the controller detects that the difference between the flow rate of the fresh air sampling flow sensor 23 and the fresh air volume required for the current pre-loaded test condition is large, or detects that the flow rate of the fresh air sampling flow sensor 23 quickly drops to 0, it can be determined that the test engine sample has a failure.

[0100] According to the pre-set fresh air system protection measures, when the fresh air control system determines that the sample has a failure, the controller opens the sixth shut-off valve 106 to open the purge and relief pipeline 16 to perform emergency pressure relief and discharge on the fresh air system. At the same time, the controller controls to automatically reduce the operating power of the fresh air fan 2 and the heat exchange power of the heat exchanger 4 to reduce the fresh air volume and heat exchange amount of the fresh air system, timely reduce the energy consumption of the fresh air system, and improve the safety of the fresh air system.

[0101] In the description of the present application, it should be noted that the orientation or positional relationship indicated by terms such as "upper" and "lower" is based on the orientation or positional relationship shown in the drawings. It is only for the convenience of describing the present application and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, so it cannot be understood as a limitation to the present application. Unless otherwise clearly specified and limited, the terms "installation", "connection", and "connection" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be directly connected or indirectly connected through an intermediate medium, and it can be the communication inside two elements. For those of ordinary skill in the art, the specific meanings of the above terms in the present application can be understood according to specific situations.

[0102] It should be noted that in this application, relational terms such as "first" and "second" are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any actual relationship or order between these entities or operations. Moreover, the term "comprising", "including" or any other variation thereof is intended to cover non-exclusive inclusion, such that a process, method, article or device comprising a series of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such process, method, article or device. Without further limitation, an element defined by the statement "comprising an..." does not exclude the presence of additional identical elements in the process, method, article or device comprising the element.

[0103] The above are only specific embodiments of this application, enabling those skilled in the art to understand or implement this application. Various modifications to these embodiments will be obvious to those skilled in the art, and the general principles defined herein can be implemented in other embodiments without departing from the spirit or scope of this application. Therefore, this application will not be limited to these embodiments shown herein, but rather will conform to the broadest scope consistent with the principles and novel features claimed herein.

Claims

1. An explosion-proof fresh air system for a hydrogen environment chamber, characterized in that: Include: A fresh air sampling pipeline (13) passes through the side wall of the environmental chamber (5) and is connected to an air inlet of a test engine sample (6) arranged in the environmental chamber (5); the fresh air sampling pipeline (13) is provided with a third stop valve (103); A normal temperature fresh air pipeline (12), one end of which is connected to the end of the fresh air inlet pipeline (13), and the other end of which is connected to the second stop valve (102); A fresh air intake pipeline (11), one end of which is connected to the second stop valve (102), and the other end of which is connected to the fresh air fan (2) through a pipeline, wherein the fresh air intake pipeline (11) is provided with a first stop valve (101); A high-low temperature fresh air pipeline (14), one end of which is connected to the pipeline on the side of the third stop valve (103) away from the test engine sample (6), and the other end of which is connected to the pipeline between the fresh air fan (2) and the second stop valve (102); the high-low temperature fresh air pipeline (14) is provided with a fourth stop valve (104), a dehumidifier (3) and a heat exchanger (4) in sequence according to the fresh air flow direction.

2. The explosion-proof fresh air system for a hydrogen-related environment chamber according to claim 1, characterized in that: The explosion-proof fresh air system further comprises a controller, wherein the controller signal is connected to the fresh air fan (2), the heat exchanger (4) and all the stop valves, and the controller obtains the operating power of the test engine sample (6) in real time; the fresh air sampling pipeline (13) is provided with a fresh air sampling pressure sensor (22) and a fresh air sampling flow sensor (23); The controller is used to preload the fresh air volume of the fresh air fan (2) according to the operating power of the test engine sample (6), and to feedback and adjust the air intake volume of the fresh air fan (2) according to the pressure value obtained from the fresh air intake pressure sensor (22) and the flow value obtained from the fresh air intake flow sensor (23).

3. The explosion-proof fresh air system for a hydrogen-related environment chamber as claimed in claim 2, characterized in that: The fresh air inlet pipeline (13) is also provided with a fresh air inlet temperature sensor (21); the high and low temperature fresh air pipeline (14) is also provided with a high and low temperature fresh air pipeline temperature sensor (31) and a high and low temperature fresh air pipeline flow sensor (33); The controller is used to dynamically adjust the heat exchange power of the heat exchanger (4) according to the temperature difference signal of the fresh air inlet temperature sensor (21) and the high and low temperature fresh air pipeline temperature sensor (31), and the flow signal of the high and low temperature fresh air pipeline flow sensor (33).

4. The explosion-proof fresh air system for a hydrogen-related environment chamber according to claim 1, characterized in that: The explosion-proof fresh air system further comprises a fresh air internal circulation pipeline (15), one end of which is connected to the pipeline between the first stop valve (101) and the fresh air blower (2), and the other end is connected to the pipeline on the side of the third stop valve (103) away from the test engine sample (6), and the fresh air internal circulation pipeline (15) is provided with a fifth stop valve (105).

5. The explosion-proof fresh air system for a hydrogen-related environment chamber as claimed in claim 4, characterized in that: The explosion-proof fresh air system further comprises a purge and release pipeline (16), one end of which is connected between the fifth stop valve (105) and the fresh air inlet pipeline (13), and the other end of which is open to the outside; the purge and release pipeline (16) is provided with a sixth stop valve (106); When the test engine sample (6) fails, or when other situations require pressure relief and blowing of the normal temperature / high and low temperature fresh air pipeline, the sixth stop valve (106) is opened to relieve pressure and blow the pipeline.

6. The explosion-proof fresh air system for a hydrogen-related environment chamber according to claim 1, characterized in that: In the fresh air intake pipeline (11), the side of the first stop valve (101) away from the fresh air blower (2) is connected to the air filter (1) through a pipeline.

7. A control method based on the explosion-proof fresh air system according to claim 1, characterized in that: The control method includes a normal temperature fresh air supply mode and a high and low temperature fresh air supply mode, and the normal temperature fresh air supply mode includes the following steps: The fourth stop valve (104) is closed, and the first stop valve (101), the second stop valve (102) and the third stop valve (103) are opened; The fresh air blower (2) is started, and the fresh air intake pipeline (11) draws fresh air, and the fresh air is transported to the test engine sample (6) through the normal temperature fresh air pipeline (12) and the fresh air sampling pipeline (13); The control method includes a high-low temperature fresh air supply mode, and the high-low temperature fresh air supply mode includes the following steps: The second stop valve (102) is closed, and the first stop valve (101), the third stop valve (103) and the fourth stop valve (104) are opened; The fresh air blower (2) is started, and the fresh air enters the high and low temperature fresh air pipeline (14) through the fresh air intake pipeline (11), is dehumidified by the dehumidifier (3) and heat exchanged by the heat exchanger (4) in the high and low temperature fresh air pipeline (14), and then enters the test engine sample (6) through the fresh air sampling pipeline (13).

8. The control method of the explosion-proof fresh air system according to claim 7, characterized in that: The fresh air sampling pipeline (13) is provided with a fresh air sampling temperature sensor (21), a fresh air sampling pressure sensor (22) and a fresh air sampling flow sensor (23); the high and low temperature fresh air pipeline (14) is provided with a high and low temperature fresh air pipeline temperature sensor (31), a high and low temperature fresh air pipeline pressure sensor (32) and a high and low temperature fresh air pipeline flow sensor (33); the explosion-proof fresh air system further comprises a controller, the controller signal is connected to the fresh air fan (2), the heat exchanger (4), all the stop valves and all the sensors, and the controller obtains the operating power of the test engine sample (6) in real time; In the normal temperature fresh air supply mode, the controller preloads the operating power of the fresh air fan (2) according to the operating power of the test engine sample (6), and adjusts the operating power of the fresh air fan (2) based on the pressure value obtained from the fresh air inlet pressure sensor (22) and the flow value obtained from the fresh air inlet flow sensor (23).

9. The control method of the explosion-proof fresh air system according to claim 8, characterized in that: The high and low temperature fresh air supply mode further includes: When the fresh air fan (2) is initially started, the controller is used to preload the operating power of the fresh air fan (2) according to the operating power of the test engine sample (6); After the fresh air fan (2) is started for a period of time, the controller adjusts the operating power of the fresh air fan (2) by feedback according to the pressure value obtained from the fresh air inlet pressure sensor (22) and the flow value obtained from the fresh air inlet flow sensor (23); at the same time, the controller is used to dynamically adjust the heat exchange power of the heat exchanger (4) according to the temperature difference signal of the fresh air inlet temperature sensor (21) and the high and low temperature fresh air pipeline temperature sensor (31), and the flow signal of the high and low temperature fresh air pipeline flow sensor (33).

10. The control method of the explosion-proof fresh air system according to claim 9, characterized in that: The explosion-proof fresh air system further comprises a fresh air internal circulation pipeline (15), one end of which is connected to the pipeline between the first stop valve (101) and the fresh air fan (2), and the other end is connected to the pipeline on the side of the third stop valve (103) away from the test engine sample (6), and the fresh air internal circulation pipeline (15) is provided with a fifth stop valve (105); the explosion-proof fresh air system further comprises a purge and release pipeline (16), one end of which is connected between the fifth stop valve (105) and the fresh air sampling pipeline (13), and the other end is open to the outside; the purge and release pipeline (16) is provided with a sixth stop valve (106); Before entering the high and low temperature fresh air supply mode, a pre-cooling / pre-heating mode is also included, and the pre-cooling / pre-heating mode includes the following steps: Open the fourth stop valve (104) and the fifth stop valve (105), and close the first stop valve (101), the second stop valve (102), the third stop valve (103), and the sixth stop valve (106); The fresh air fan (2) is started, and the gas retained in the pipeline passes through the fresh air internal circulation pipeline (15) and circulates through the fresh air fan (2) before entering the high and low temperature fresh air pipeline (14) for dehumidification and pre-cooling / pre-heating. The gas then enters the fresh air internal circulation pipeline (15) again and circulates through the fresh air fan (2) before entering the high and low temperature fresh air pipeline (14) for secondary dehumidification and pre-cooling / pre-heating. This process is repeated until the gas retained in the pipeline reaches the temperature value set by the fresh air inlet temperature sensor (21).

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