A forest lightning ignition and spread simulation device and simulation method

Abstract

The present invention discloses a forest lightning ignition and spread simulation device, including a main experimental box, an air conditioner for adjusting the temperature, humidity and air volume of the inlet air is provided on one side of the main experimental box, and an exhaust duct is provided on the other side; a fuel bed is provided at the bottom of the main experimental box, the fuel bed is laid on the electrode, and a lightning rod is provided at the top of the main experimental box, and the electrode and the lightning rod are both connected to the impulse current generator. The device of the present invention also includes an air inlet shutter, a rain simulation device, a thermal radiation lamp, an ultraviolet lamp, a carbon monoxide concentration detector, a high-speed camera, etc. The present invention can provide different temperatures, humidity, rainfall, wind speed, wind direction, thermal radiation and ozone, and can simulate the influence of different mountain trends on lightning ignition and spread. It has the advantages of low cost, high safety, strong repeatability, and a simulated environment that is more in line with the natural lightning process.

Description

Technical Field

[0001] The invention relates to the field of lightning simulation research, and in particular to a forest lightning ignition and spread simulation device and a simulation method. Background Art

[0002] Forest lightning fire is an important way for nature to interfere with forest ecosystems. It is characterized by randomness, high concurrency, and difficulty in firefighting. Lightning fire accounts for a large proportion of forest fires in terms of the number of fires and the burned area. Taking China as an example, lightning fires are mainly distributed in the Greater Khingan Range in Heilongjiang, Hulunbuir in Inner Mongolia, and the Altai Mountains in Xinjiang, and are most concentrated in the Greater Khingan Range. In recent years, with global warming, extreme weather and climate events such as high temperatures and dry weather in forest areas in summer have shown a clear increasing trend. The warming and drying climate has caused forest lightning fires in forest areas in summer to increase year by year.

[0003] In view of the harm caused by lightning fire to forestry production and ecological construction, all countries attach great importance to the research on lightning fire. At present, the research is mainly carried out from two aspects: its influencing factors and fire risk prediction. However, lightning fire research involves many disciplines and has strong interdisciplinary nature. There are great differences in research angles in different fields. In addition, there is currently little research on the behavior mechanism of lightning fire, and the experimental methods and theoretical support are mostly based on the results of the 1970s and 1980s.

[0004] Previous studies have found that lightning ignition does not necessarily lead to fire spread. Most lightning strikes only cause combustibles to ignite instantly and then extinguish naturally. Only a small number of ignited combustibles can continue to burn and eventually form a fire. Currently, there is a lack of equipment to simulate the ignition process and fire spread process of lightning strikes. Summary of the invention

[0005] The purpose of the present invention is to overcome the shortcomings and deficiencies of the prior art and to provide a forest lightning ignition and spread simulation device and simulation method, which can simulate the environmental conditions of forest lightning fires, study the possibility of combustibles being ignited by lightning, and simulate the possibility of fire spread after ignition under specific circumstances, thereby laying a foundation for the study of the behavior mechanism of lightning fires.

[0006] The purpose of the present invention is achieved through the following technical solutions: a forest lightning ignition and spread simulation device, including a main experimental box, an air conditioner for adjusting the temperature, humidity and air volume of the inlet air is provided on one side of the main experimental box, and an exhaust pipe is provided on the other side; a fuel bed is provided at the bottom of the main experimental box, the fuel bed is laid on the electrode, and a lightning rod is provided at the top of the main experimental box, and the electrode and the lightning rod are both connected to an impulse current generator. The present invention uses an impulse current generator to provide current to the electrode and the lightning rod, and a lightning strike can be formed between the two. The fuel bed can perform lightning simulation experiments under different inlet air temperatures, humidity and air volumes.

[0007] Preferably, the lightning rod is arranged in a sleeve, and the position of the lightning rod in the sleeve is adjustable, so that the distance between the lightning rod and the fuel bed can be adjusted, and it is also convenient to replace the lightning rod after it is ablated.

[0008] Furthermore, the sleeve is made of thermosetting insulating plastic, which is convenient for threading and fixing the lightning rod.

[0009] Preferably, an air inlet shutter for adjusting the air direction is provided between the air conditioner and the main experimental box.

[0010] Preferably, a rain simulation device is also provided at the top of the main experimental box, and the rain simulation device includes a nozzle and a flow control valve. The nozzles are evenly distributed in the top area, the flow control valve is arranged on the connecting pipe between the nozzle and the external water tank, and a drain outlet is provided at the bottom of the main experimental box.

[0011] Preferably, a thermal radiation lamp for simulating sunlight is provided on the top of the main experimental box.

[0012] Preferably, an ultraviolet lamp for generating ozone is provided on the top of the main experimental box.

[0013] Preferably, a tilt adjustment device for tilting the electrode is provided at the lower portion of the electrode.

[0014] Furthermore, the tilt adjustment device includes two bolts, which are arranged on both sides of the lower end of the electrode, one of the bolts is hinged to the electrode, and the other bolt is in smooth contact with the electrode.

[0015] Preferably, a carbon monoxide concentration detector is provided in the exhaust duct.

[0016] Preferably, the main experimental box is made of tempered glass material.

[0017] Preferably, a high-speed camera for photographing the combustion process of internal combustibles due to lightning strike is provided on the outside of the main experimental box.

[0018] A simulation method based on the above-mentioned forest lightning ignition and spread simulation device comprises the steps of:

[0019] Turn on the air conditioner, adjust the temperature, humidity, wind speed and wind direction of the incoming air; adjust the rainfall, thermal radiation lamp and ultraviolet lamp; connect the lightning rod, electrode and impulse current generator lead wire;

[0020] Adjust the distance and angle between the lightning rod and the electrode, and load the fuel bed;

[0021] Adjust the high-speed camera shooting parameters;

[0022] The impulse current generator discharges to simulate a lightning strike;

[0023] The discharge process, as well as the process of fire extinguishing or forming and spreading after the discharge is completed, is continuously observed by a high-speed camera, while the carbon monoxide concentration is measured at the same time.

[0024] Compared with the prior art, the present invention has the following advantages and beneficial effects:

[0025] 1. The device of the present invention has the advantages of low cost, high safety, strong repeatability, and a simulated environment that is more consistent with the natural lightning strike process.

[0026] 2. The device of the present invention can provide different temperature and humidity, rainfall, wind speed, wind direction, thermal radiation and ozone, and can simulate the influence of different mountain trends on lightning ignition and spread. It increases the number of experimental conditions that can be changed, which is conducive to analyzing the influence of different factors.

[0027] 3. The present invention can study the extinguishing and fire spreading process after lightning strike through the carbon monoxide concentration detector, and can observe the instantaneous action process of lightning strike which has not been reported before through the high-speed camera. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] Figure 1 It is a structural schematic diagram of the device of the present invention. DETAILED DESCRIPTION

[0029] The present invention is further described in detail below in conjunction with embodiments and drawings, but the embodiments of the present invention are not limited thereto.

[0030] Example

[0031] The present embodiment is a forest lightning ignition and spread simulation device, which can simulate different temperatures and humidity, rainfall, wind speed, wind direction, thermal radiation and ozone levels, and can also simulate the impact of different mountain terrains on lightning ignition and spread, making the simulation closer to natural lightning strikes and obtaining more realistic effects, which is convenient for researchers to conduct indoor experimental analysis.

[0032] For details, see Figure 1 , including an air conditioner 1, an air inlet shutter 2, a main experimental box 3, a nozzle 4, a thermal radiation lamp 5, a sleeve 6, a lightning rod 7, an ultraviolet lamp 8, a flow control valve 9, a carbon monoxide concentration detector 10, an exhaust pipe 11, a high-speed camera 12, a fuel bed 13, an adjustment bolt 14, an electrode 15, and a drain outlet 16.

[0033] Among them, the main experimental box 3 is made of tempered glass material, which helps to increase the weight of the box and avoid vibration of the box when struck by lightning. At the same time, the use of glass material is also conducive to the high-speed camera 12 to capture the combustion process of internal combustibles caused by lightning.

[0034] At the beginning of the experiment, the outdoor air passes through the air conditioner 1 and becomes air that meets the temperature, humidity and air volume requirements. The wind direction of the air entering the main experimental box 3 can be adjusted through the air inlet louver 2, thereby simulating different wind fields during natural lightning strikes and subsequent processes. The exhaust air is discharged through the exhaust duct 11 on the other side of the main experimental box.

[0035] To simulate the forest lightning strike and the subsequent raining process, a raining simulation device can be used on the top of the main experimental box. The raining simulation device includes a nozzle 4 and a flow control valve 9. The nozzles 4 are evenly distributed in the top area. The flow control valve 9 is set on the connection pipe between the nozzle 4 and the external water tank. The rainfall is controlled by the flow control valve. A drain port is provided at the bottom of the main experimental box 3 to facilitate the drainage of accumulated water.

[0036] The thermal radiation lamp 5 in the main experimental box is used to simulate sunlight irradiation. The ultraviolet lamp 8 is used to generate ozone to simulate the ozone environment when lightning strikes.

[0037] The lightning rod 7 and the electrode 15 are connected to an external impulse current generator to simulate the lightning discharge process. The lightning rod 7 and the sleeve 6 are pressed tightly by screws on both sides. The lightning rod 7 moves in the sleeve 6 and can flexibly adjust the distance from the fuel bed 13. In addition, the lightning rod 7 can be easily replaced after ablation. The sleeve 6 is made of thermosetting plastic, which is easy to open the thread and can be insulated from the lightning rod 7.

[0038] The fuel bed 13 is placed on the electrode 15. There are two adjustment bolts at the bottom of the electrode 15, of which the left bolt is hinged to the electrode 15, and the right bolt is in smooth contact with the electrode 15. By adjusting the depth of the bolts on both sides, the distance between the electrode 15 and the lightning rod 7 can be changed, and the angle between the electrode 15 and the lightning rod 7 can also be changed. In this way, the influence of different mountain trends on lightning ignition can be simulated; at the same time, the influence of different slopes on subsequent fire spread after ignition can also be simulated.

[0039] The external high-speed camera 12 is used to capture the ignition process of the fuel bed 13 when it is struck by lightning. Since the lightning discharge process is very short, it is necessary to use the high-speed camera 12 to capture it. By taking pictures with the high-speed camera 12, the process of current attachment, heating ignition and mechanical destruction during lightning discharge can be observed.

[0040] The carbon monoxide concentration detector 10 in the exhaust pipe 11 is used to detect the carbon monoxide concentration in the main experimental box 3, so as to help study the extinguishing and fire spreading process after lightning strike.

[0041] The simulation method of the forest lightning ignition and spread simulation device of this embodiment includes the steps of:

[0042] S1. Turn on the air conditioner and adjust the temperature, humidity, wind speed and wind direction of the incoming air;

[0043] S2. Adjust the rainfall;

[0044] S3. Adjust the thermal radiation lamp and the ultraviolet lamp;

[0045] S4. Connect the lightning rod, electrode and impulse current generator lead wire;

[0046] S5. Adjust the distance and angle between the lightning rod and the electrode, and load the fuel bed;

[0047] S6. Adjust the shooting parameters of the high-speed camera;

[0048] S7, discharge;

[0049] S8. Measure the carbon monoxide concentration and continuously observe the process of fire extinguishing or forming and spreading after the discharge ends.

[0050] Of course, the above simulation is based on Figure 1 In actual applications, the various public simulations implemented on the device shown can be adaptively selected for wind direction, radiation, ozone level, mountain trends, rainfall, etc. according to different on-site environments without the need to adjust all of them.

[0051] The above is only a specific embodiment of the present invention, but the protection scope of the present invention is not limited thereto. Any technician familiar with the technical field can easily think of various equivalent modifications or replacements within the technical scope disclosed by the present invention, and these modifications or replacements should be included in the protection scope of the present invention. Therefore, the protection scope of the present invention shall be based on the protection scope of the claims.

Claims

1. A device for simulating the ignition and spread of lightning in forests, It is characterized in that The main body experiment box comprises an air conditioner for adjusting the temperature, humidity and air volume of the inlet air on one side of the main body experiment box, and an exhaust pipe on the other side; a fuel bed is provided at the bottom of the main body experiment box, the fuel bed is laid on the electrode, and a lightning rod is provided at the top of the main body experiment box, and both the electrode and the lightning rod are connected to the impulse current generator; A rain simulation device is also provided on the top of the main experimental box, and the rain simulation device includes a nozzle and a flow control valve. The nozzles are evenly distributed in the top area, and the flow control valve is arranged on the connection pipe between the nozzle and the external water tank. A drain port is provided at the bottom of the main experimental box. A thermal radiation lamp for simulating sunlight is provided on the top of the main experimental box; An ultraviolet lamp for producing ozone is provided on the top of the main experimental box; The lightning rod is arranged in a casing, and the position of the lightning rod in the casing is adjustable; The lower part of the electrode is provided with a tilt adjustment device for tilting the electrode, and the tilt adjustment device includes two bolts, which are arranged on both sides of the lower end of the electrode, one of which is hinged to the electrode, and the other bolt is in smooth contact with the electrode; An air inlet shutter for adjusting the air direction is provided between the air conditioner and the main experimental box; A carbon monoxide concentration detector is installed in the exhaust duct; A high-speed camera is installed on the outside of the main experimental box to record the combustion process of internal combustibles caused by lightning.

2. The forest lightning ignition and spread simulation device according to claim 1, It is characterized in that The main experimental box is made of tempered glass material.

3. A simulation method based on the forest lightning ignition and spread simulation device according to any one of claims 1-2, It is characterized in that Includes steps: Turn on the air conditioner, adjust the temperature, humidity, wind speed and wind direction of the incoming air; adjust the rainfall, thermal radiation lamp and ultraviolet lamp; connect the lightning rod, electrode and impulse current generator lead wire; Adjust the distance and angle between the lightning rod and the electrode, and load the fuel bed; Adjust the high-speed camera shooting parameters; The impulse current generator discharges to simulate a lightning strike; The discharge process, as well as the process of fire extinguishing or forming and spreading after the discharge is completed, is continuously observed by a high-speed camera, while the carbon monoxide concentration is measured at the same time.

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