WO2017035830A1

WO2017035830A1 - Forest fire intensity simulator and method for use thereof

Info

Publication number: WO2017035830A1
Application number: PCT/CN2015/088950
Authority: WO
Inventors: 张水锋; 张思玉
Original assignee: 南京森林警察学院
Priority date: 2015-09-06
Filing date: 2015-09-06
Publication date: 2017-03-09
Also published as: AU2015381974B2; AU2015381974A1; CN105723438A; CN105723438B

Abstract

A forest fire intensity simulator, comprising a simulator body consisting of a reaction chamber (1), a heating unit, a smoke collecting unit (2), and a temperature sensor (4). The heating unit is arranged inside the reaction chamber (1). The temperature sensor (4) comprises temperature probes, a lead, and a temperature indicator. The smoke collecting unit (2) is arranged outside the reaction chamber (1) and is connected to the reaction chamber (1) by a pipe. The simulator reduces the costs of a forest fire simulation experiment, avoids air pollution caused by the smoke generated by a forest fire burning experiment, can more safely and precisely obtain data of heated soil, and facilitates the prevention and control of soil erosion as well as the vegetation restoration in burned areas after forest fires.

Description

Forest fire intensity simulator and using method thereof

Technical field

The invention relates to a simulation device for a forest fire secondary disaster research, in particular to a forest fire intensity simulator and a using method thereof.

Background technique

About 4% of the world's forest area suffers from disaster losses each year, and the destruction of forest resources by forest fires accounts for nearly one-third of the lost forest resources. At present, forest fires occur frequently around the world, and fires occur every year. More than 220,000 times, more than 6.4 million hm2 of forests were burned, accounting for more than 0.23% of the world's forest coverage. China is a Shaolin country. The national forest coverage rate is only 20.36%. At the same time, it is a country with frequent forest fires. The annual average forest fires are 16,000 times, and the annual average fire area is 9×105hm2.

The impact of fire on forest ecosystems is complex, from reducing above-ground biomass to physical properties, chemical properties, microbial degradation processes and fine root growth in the subsurface. Fire can dramatically change the environmental conditions in a short period of time, including rapidly changing the physical and hydrological functions of forest soils, changing the C/N ratio, exacerbating erosion, leaching and denitrification, leading to soil nutrient loss, microbial population and related processes. Changes that affect the nutrient cycling and distribution of the entire forest ecosystem. It is beneficial or harmful to the effects of the ecosystem, depending on the time and intensity of the fire. In order to study the effects of fire on forest soils, scientific experiments are needed.

technical problem

In the current forest fire prevention scientific research process, the impact of forest fires on the soil is mainly studied in the following two ways:

1. Forest fire burning control test: Burning at a test area of a certain area (if the combustibles are not enough, the combustibles should be collected from the vicinity of the same forest to the spot burning area), according to the blackening height of the forest, flammable The amount of material (load) is used to estimate the intensity of forest fire burning. After the end of the burn, soil and plant samples were taken and then analyzed in the laboratory. Disadvantages of this method: environmental pollution is large; fire intensity is difficult to control; soil heating intensity is uneven, resulting in large test error.

2. Take out the undisturbed soil in the forest land, transport it back to the laboratory, heat it with a tool such as a muffle furnace, set the heating temperature according to the requirements of the fire intensity. After the heating is completed, the soil is cultivated in the laboratory to simulate the outdoor environment. The disadvantage of this method is that it destroys the original ecosystem of the soil and causes a large test error.

Technical solution

OBJECT OF THE INVENTION: The object of the present invention is to remedy the deficiencies of the prior research techniques and to provide a forest fire intensity simulator and method of use thereof.

Technical solution: a forest fire intensity simulator includes a body, the simulator body is composed of a reaction chamber, a heating unit, a smoke collecting unit and a temperature sensor, and the heating unit is disposed in the reaction chamber, and the temperature sensor includes a temperature probe and a lead wire. The temperature display is arranged, and the temperature probe is placed in different depth soil layers, and the smoke collecting unit is disposed outside the reaction chamber and connected to the reaction chamber through a pipeline.

Preferably, the heating unit is a heating wire disposed inside the reaction chamber.

Preferably, the electric heating wire is formed by connecting U-shaped electric heating wires.

Preferably, the heating unit is composed of a combustion nozzle and an input pipe connected thereto, and the combustion nozzle is uniformly disposed at the top of the reaction chamber, one end of the input pipe is connected to the combustion nozzle, and the other end is connected to the gas cylinder or the liquid bottle.

Preferably, the smoke collecting unit is internally provided with a water bath nozzle for sedimenting and adsorbing soot generated in the reaction chamber.

A method of using a forest fire intensity simulator includes the following steps:

1) When used in the field or in the laboratory, dig a groove matching the bottom edge of the reactor in the field research area or indoor undisturbed soil surface, about 3cm deep, insert the bottom of the reaction chamber into the groove, and fix it around to prevent running. fire;

2) Set the heating temperature/strength and reaction time according to the fire level, and carry out the experiment;

3) At the same time as the experiment, open the smoke collecting unit and collect the soot;

4) After the end of the experiment, the reaction chamber was removed, and the soil samples were taken out in layers according to the experimental requirements, and physical, chemical and biological properties were analyzed.

Beneficial effect

Advantageous Effects: The present invention uses a simulator to perform a point-burning experiment, which greatly reduces the cost of a forest fire simulation experiment; and sets a smoke collecting unit outside the reaction chamber to set off the smoke generated by the reaction, thereby avoiding the smoke generated by the forest fire burning test. The air pollution caused by the operation, and the operation in the simulator, the firepower can be controlled; the heating wire or the combustion nozzle in the reaction chamber is heated evenly, does not run fire, and can obtain soil experimental data safer and more accurately, which is beneficial to forest fires. Soil erosion prevention and control and vegetation restoration work in the burned area.

DRAWINGS

1 is a schematic structural view of Embodiment 1 of the present invention;

2 is a schematic structural view of Embodiment 2 of the present invention.

Embodiments of the invention

In the present invention, the reactor is made of an inorganic non-metallic refractory material having a commercial refractoriness of not less than 1,580 ° C, such as a carbon composite refractory material, a zirconium refractory material, etc., and the electric heating wire is mainly an iron chromium aluminum alloy electric furnace wire and an iron nickel alloy. There are two types of electric furnace wire, which have strong oxidation resistance, large electric resistance and high use temperature. Gas heating mainly uses flammable gases such as carbon monoxide and oxygen, hydrogen and oxygen; liquid heating mainly uses organic liquids such as ethanol and gasoline.

Example 1:

A forest fire intensity simulator, as shown in Fig. 1, is composed of a reaction chamber 1, a heating unit, a smoke collecting unit 2 and a temperature sensor 4, which are not closed at the bottom, the heating unit is disposed in the reaction chamber 1, and the collecting unit 2 is disposed at Outside the reaction chamber 1, it is connected to the reaction chamber 1 through a pipe. In this embodiment, the heating unit is a heating wire 31 disposed at an intermediate portion of the reaction chamber 1, and the heating wire is connected by a U-shaped electric heating wire. The temperature sensor 4 is composed of a temperature probe, a lead wire, a temperature display, and the temperature probe is a plurality of And placed in different depth soil layers to measure soil temperature.

Simulator use method and working principle: When the simulator in this embodiment works, a groove corresponding to the bottom edge of the reactor is digging in the field of the field research area or the indoor undisturbed soil, about 3 cm deep, and the reaction chamber is used. Insert the bottom into the groove, fix it around, open the U-shaped heating wire switch for heating, and set the required temperature range and heating time according to the test design. The temperature of the heating wire and the temperature of each layer of soil are sensed by the temperature probe. On the temperature display, at the same time, it is necessary to open the switch of the unit 2 of the collecting smoke, and the water bath head 34 of the collecting unit 2 sprays the water mist to set the soot to prevent the emission of harmful smoke. After the end of the work, the reaction chamber 1 was removed, and the soil samples were taken out in layers according to the experimental requirements, and physical, chemical, and biological properties were analyzed.

Example 2:

A forest fire intensity simulator, as shown in Fig. 2, comprises a body, which is composed of a reaction chamber 1, a heating unit, a smoke collecting unit 2 and a temperature sensor 4, which are not closed at the bottom, and the temperature sensor 4 is composed of a temperature probe, a lead wire and a temperature display. The temperature probes are several and placed in different depth soil layers for measuring soil temperature. The heating unit is disposed in the reaction chamber 1, and the collecting unit 2 is disposed outside the reaction chamber 1, and is connected to the reaction chamber 1 through a pipe. In this embodiment, the heating unit is composed of a combustion nozzle 32 and an input pipe 33 connected thereto, and the combustion nozzle 32 is evenly disposed at the top of the reaction chamber, one end of the input pipe 33 is connected to the combustion nozzle, and the other end is connected to the gas cylinder or the liquid bottle, and the smoke collecting unit 2 There is a water bath nozzle 34 inside for collecting and adsorbing the soot generated in the reaction chamber 1.

When in use, a groove corresponding to the bottom edge of the reactor is digging in the field of the field research area or the indoor undisturbed soil, about 3 cm deep, and the bottom of the reaction chamber is inserted into the groove and fixed around. The gas or liquid is input through the input pipe, and the input reaction amount of the gas or liquid is converted according to the fire intensity required for the test and the calorific value of the gas or liquid per unit volume (the standard of the fire intensity is shown in Table 1).

Table 1 Classification criteria for surface fire and canopy fire intensity

Fire level	Low intensity	Medium intensity	high strength	Ultra high strength
Flame height ( m )	less than 1	1-3	3-5	Greater than 5
Fire intensity (kw/m)	Less than 300	300-2700	2700-7000	Greater than 7000

Table 1 shows the relationship between the fire intensity and the calorific value of combustion, and the input reaction amount of gas or liquid can be converted by two formulas.

Formula 1: (threshold of intensity level) / (edge length of simulator) = (total heat of combustibles)

Formula 2: (total calorific value of combustibles) / (heat of gas or liquid per unit volume) = (gas/liquid fuel volume)

The ignition is performed by a combustion nozzle, and the undisturbed soil at the bottom of the reactor is burned. The flame temperature and the temperature of each layer of soil are sensed by a temperature probe and displayed on the temperature display. At the same time of the experiment, it is necessary to open the switch of the unit 2 of collecting smoke, and the water bath nozzle 34 of the collecting unit 2 sprays the water mist to set the soot to prevent the emission of harmful smoke. After the work is finished, the reaction chamber 1 is removed and layered according to the experimental requirements. The soil samples were taken out for physical, chemical and biological analysis.

Compared with the prior art, the embodiment reduces the cost and is safer; the heating wire or the combustion nozzle is used as the heating unit, and the heating is uniform, which facilitates more accurate experiments, better analyzes the experimental results, and the invention The design greatly reduces the possibility of environmental pollution and is environmentally friendly.

Claims

A forest fire intensity simulator includes a body, wherein the simulator body is composed of a reaction chamber (1), a heating unit, a smoke collecting unit (2), and a temperature sensor (4), and the heating unit Provided in the reaction chamber (1), the temperature sensor (4) comprises a temperature probe, a lead wire, a temperature display, and the temperature probe is placed in different depth soil layers, and the smoke collecting unit (2) is disposed in the reaction chamber (1) Outside, it is connected to the reaction chamber (1) through a pipe.
A forest fire intensity simulator according to claim 1, wherein said heating unit is a heating wire (31) disposed inside the reaction chamber (1).
The forest fire intensity simulator according to claim 2, wherein said heating wire (31) is formed by connecting U-shaped electric heating wires.
A forest fire intensity simulator according to claim 1, wherein said heating unit is composed of a combustion nozzle (32) and an input pipe (33) connected thereto, said combustion nozzle (32) being uniformly disposed on At the top of the reaction chamber (1), one end of the input pipe (33) is connected to the combustion nozzle, and the other end is connected to a gas cylinder or a liquid bottle.
The forest fire intensity simulator according to claim 2 or 4, characterized in that: the collecting unit (2) is provided with a water bath nozzle (34) for adsorbing and adsorbing soot generated by the reaction chamber (1). .
A method of using a forest fire intensity simulator according to claim 1, comprising the steps of:

1) When used in the field or in the laboratory, dig a groove matching the bottom edge of the reactor in the field research area or indoor undisturbed soil surface, about 3cm deep, insert the bottom of the reaction chamber into the groove, and fix it around to prevent running. fire;

2) set the heating temperature/fuel volume and reaction time according to the fire intensity level, and carry out the experiment;

3) At the same time as the experiment, open the smoke collecting unit and collect the soot;

4) After the end of the experiment, the reaction chamber was removed, and the soil samples were taken out in layers according to the experimental requirements, and physical, chemical and biological properties were analyzed.