What is the connection between combustion and fire extinguishing, and what is the root of fire extin

1 Basic principles of fire extinguishing.

The combustion of a substance must meet three necessary conditions at the same time, namely combustibles, combustibles and ignition sources. According to these basic conditions, all fire extinguishing measures are aimed at destroying the combustion conditions that have been formed, or terminating the chain reaction of combustion to extinguish the fire and control the fire within a certain range, so as to minimize the fire loss. This is the basic principle of fire extinguishing.

Cooling method: such as extinguishing the fire of general solid matter with water, absorbing a large amount of heat through water, so that the temperature of the burning material is rapidly reduced, and finally the combustion is terminated.

Asphyxiation method: such as using carbon dioxide, nitrogen, water vapor, etc. to reduce oxygen concentration, so that combustion can not be sustained.

Isolation method: such as using foam fire extinguishing agent to extinguish the fire, through the resulting foam covering the surface of the combustible body, while cooling the effect, the combustible material is isolated from the flame and air to achieve the purpose of fire extinguishing.

Chemical inhibition method: such as using dry powder fire extinguishing agent to destroy the chain reaction of combustion through chemical action and stop combustion.

Knowing the conditions of the burning, and eliminating these conditions can extinguish the fire. The conditions are combustibles, oxygen, ignition points. Removing combustibles, isolating combustibles from oxygen, and lowering the temperature are the principles of fire extinguishing.

When it burns out, the fire is extinguished.

Fire extinguishing should be based on the three conditions of combustion, block one or more of them to achieve the purpose of fire extinguishing.

The conditions for burning are:

Reach the ignition point.

with oxygen. To extinguish a fire is to do the opposite.

Isolate oxygen. Reduce the temperature of the environment below the ignition point.

There is no fire extinguishing without burning.

Huh

Hearing **, most people will think about using water to extinguish the fire or using sand to extinguish the fire, and if possible, they will also use a fire extinguisher to extinguish the fire. When they hear about extinguishing fire, many people may think that it is very unrealistic and has no scientific basis, but in fact, fire extinguishing is a very effective and scientific way to extinguish fires, mainly used in forest fires. When we find that the nearby mountain is on fire, we will find that when the firefighters come, the fire is not only the fire, but the light is not getting smaller but getting bigger and bigger, and many people will be very anxious, but in fact, there is no need to worry, because the fire is not a bad thing, but the firefighters are using the fire to extinguish the fire, so the fire is bigger because the firefighters are igniting the fire.

Professionals explained that the principle of extinguishing a fire with fire is actually to isolate the oxygen and combustibles needed for the combustion of two mountain fires in a short period of time when they meet, so as to achieve a fire extinguishing effect. When the flame burns rapidly, there will be a lot of updrafts around it, and at this time, the air currents from other directions will automatically rush in the direction of the flame, forming a heat wave, that is, wind. If you light another fire in a place where a fire has already occurred, two fires will run in the same direction, so that the wind will extinguish the flames.

But fire extinguishing is a way that requires a lot of means, and it also needs to be used in a very good environment, such as when the wind and wind direction are very stable, so it is generally used to extinguish the fire in a relatively open place, if the house is on fire, it is not recommended to use this way to extinguish the fire, because first of all, we are not like firefighters, we have professional knowledge and professional protective equipment, if we use this way, it is likely to cause the flame to become bigger and bigger, It is difficult to extinguish and endangers one's own health and safety.

Fire extinguishing is incorrect, and in most cases it is judged based on the fire situation. Extinguish the fire with a fire extinguisher.

When the fires on both sides are quickly merged together, oxygen and combustibles are used to extinguish the fire, so that there is no combustible material in the isolation zone, and the fire is prevented from spreading.

Fire extinguishing is not about burning oxygen, it's about burning combustibles in advance. In the case of uncontrollable fire, and at the same time the fire and wind are quite stable, it can be extinguished in a way that extinguishes the fire for a while.

Extinguishing a fire with fire is the same as "fighting poison with poison", which is to manually ignite the fire in the direction of the fire, and when the two fire points intersect, it will not continue to spread, thereby reducing the area and loss of the fire.

This is where everyone has been paying attention latelyOn the evening of August 21Beibei District, ChongqingHutou in Xiema Street is a pei villageSudden fire, and the fire is relatively large, of course, what people admire more are those firefighting heroes and the common people who continue to provide suppliesAfter five days, after the efforts of all parties, the stove belt finally won the victory.

And in the tug-of-war with this wildfire, this time it was integratedThe right time and placewithAnd the method of "extinguishing fire" is very important, at first because the weather continues to be dry and the terrain is special, it is still more difficult to extinguish the fire, if the wind speed and wind direction are constantly changing, then "extinguishing the fire with fire" still has a certain risk, so the comrades of the local meteorological bureau also report the meteorological dynamics every half an hour, and many people may rarely hear of the "fire extinguishing fire" method in their daily life, because the occurrence of mountain fires is still relatively rare, so with the help of the power of nature has become the final step to win.

"Extinguishing fire" is called "anti-burning method" in the mouths of the common peopleIt is the docking of the artificial ignition fire head (fire line) with the forest fire burning in the opposite direction, so that the joint suddenly loses the burning condition. The advantages of this approach are:It is highly efficient and does not require special equipment, which is very effective in controlling large-area, high-energy forest fires. However, this method of "fire attack" has extremely high requirements for the direction of the wind, and the slightest carelessness will result in a complete loss, so it must be organized and implemented by experienced commanders.

The wildfires in Chongqing's Beibei District have a favorable wind directionEasterly windsAfter the first time the Meteorological Bureau first went to the next two hours after the easterly wind, the fire scene was immediately arranged to ignite the hidden hulu, a fire ignited from the fire isolation zone, and finally the two fire dragons met, and the method workedThe wildfire was brought under control at around 11 p.m. on August 25。The wildfires in Beibei District, Chongqing, have made many people see the power of science and technology and the motherland, and we can see on TV that we can see multiple emergency rescue, forest firefighting, thousands of volunteers and enthusiastic people's hearts twisted into a rope and continue to provide food and equipment to the soldiers in front, which makes everyone's hearts warm.

I believe that many people are like me, in their minds it sounds very simple, but this method is the experience of the people's soldiers to risk their lives, as the saying goes, "fire and water are ruthless" This is a normal natural phenomenon, but everyone has to reflect on itWhy wildfires are so frequentGlobal warming has become an indisputable fact, what we can do is to protect the environment, so that future generations can enjoy a more beautiful and greener natural environment.

The basic principle of fire extinguishing is: use suitable fire extinguishing equipment combined with suitable fire extinguishing measures to destroy the combustion conditions that have been formed, or stop the chain reaction of the fire continuing to burn vertically, so as to let the Dayu Wangyun fire be gradually extinguished and control the fire in a certain area, so as to achieve the purpose of minimizing fire losses.

The condition of combustion is that there is a certain starting energy, reaching a certain temperature and concentration, in order to produce a fast enough reaction speed to ignite. The principle of fire extinguishing is to prevent the occurrence of combustion or the continuation of combustion by preventing the completion of the fire triangle.

During combustion, momentum, heat and mass are transferred between fuel, oxygen and combustion products, forming a multi-component concentration ladder of flames.

Complex structure of degree and non-isothermal two-phase flow.

These transfers inside the flame are achieved by laminar molecular transfer or turbulent micromass transfer, industrial combustion devices.

The turbulent micromass transfer is the main one.

Exploring the laws of velocity, concentration, and temperature distribution in the combustion chamber and how they interact with each other is derived from fluid mechanics.

Angle to study the important content of the combustion process.

Due to the complexity of the combustion process, experimental technology is the main means of combustion engineering. It has developed in recent years.

The computational combustion science is based on momentum and energy by establishing a physical model of the combustion process.

Numerical solutions of differential equations such as quantity and chemical reactions have made significant progress in the research and charging of engineering problems such as the flow field in the combustion equipment, the ignition of the fuel and the heat transfer process of combustion, and the stability of the flame.

Three conditions are required for combustion: combustibles; oxygen (air); Reach the ignition point.

Because combustion and extinguishing are relative, there are three principles for extinguishing fires: removing all combustibles, or isolating combustibles from other items. Isolation of oxygen (air); Lower the temperature to the point of ignition.

Fire extinguishing method: prevent the completion of the fire triangle, keep the combustible environment cool and ventilated (special substances isolate the air); For open fires that have occurred, use fire-fighting sand, fire-fighting water, special fire extinguishers and other tools to achieve the purpose of extinguishing fires.

For the occurrence and development of combustion, there must be three necessary conditions, namely, combustibles, combustibles and ignition sources, which are commonly referred to as the three elements of combustion.

Combustion conditions: 1. The temperature reaches the ignition point.

2. There are accelerants.

3. It is combustible.

3 points are required).

Fire extinguishing principle: 1. Isolate the accelerant.

2. Reduce the temperature below the ignition point (not to lower the ignition point, the ignition point cannot be reduced) 3. Isolate combustibles (extinguishing the fire when it reaches one point of 3 points.) ）

Combustion conditions: combustibles, oxygen, fire extinguishing principle when the ignition point is reached: remove the combustibles, isolate the oxygen, and reduce the temperature below the ignition point.

Fire requires oxygen to burn, and fire extinguishers make it impossible to burn in a vacuum by spraying liquid or powder.

Some are insulated from oxygen, and some substances are not combustible.

It can have the effect of insulating the air.

Fire protection fully reflects the humanistic care of the Chinese people. Not only is it as simple as extinguishing a fire, but it also includes the meaning of rescuing the wounded and property. This is the best summary of fire handling.

In the event of a fire, the first priority is to save people and save people. Firefighting can also save people. Therefore, excellent Chinese call fire fighting "fire fighting".

In addition, "."Extinguishing a fire" sounds more urgent and necessary than extinguishing a fire. It is more emotional, emphasizing the slangGas.

Both forest fires and urban fires are terrible and threaten people's lives and property. However, at this time, there is always a group of outstanding figures who bear the brunt of it, sacrificing themselves to save our interests. They are heroes worthy of honor, worthy of our eternal praise!

A hero is a hero because he always instills a sense of responsibility in his heart. When danger comes, he makes a choice first.

I still remember the little hero Raining that I learned in Chinese class. His courageous act in fighting fires has become an example that many have praised and remembered. I don't recommend kids learning this behavior here.

After all, they are young and must first learn strong self-protection skills. However, Laining's deeds deserve to be remembered and praised forever! Whenever there is a fire, they always risk their lives to rush to the front line to save people and save people, fighting the relentless fire.

Every summer and winter are the seasons with the highest frequency of fires, especially in the summer! In summer, when the electricity load and household appliances are aging, it is most likely to cause disasters. At this time, it was our people's army, the firefighters, who were able to protect our lives and property.

The fire brigade is a real fighting force in peacetime. This requires a great deal of professional risk. The scene of fires, car accidents, and other accidents is very dangerous.

Any carelessness can lead to life-threatening injuries.

When a fire occurs, it is already a disaster, and if it is called firefighting, it is even more urgent, such as the first in the wok, which is still under control, and it is called fire extinguishing.

Because fires generally bring disasters, such as people or houses being burned down, it is generally called firefighting.

In ancient China, there was no word for "firefighting". At that time, the ** that managed the fire was called "fire policy"; Laws that prevent or extinguish fires are called "fire bans"; Extinguishing a fire is called "firefighting".

Because they all want to save the property and people under the fire, it is called firefighting, not extinguishing fire, which means that you don't need to save anything inside.

Fire is a kind of disaster, firefighting is mostly used in houses, buildings are on fire, mainly refers to extinguishing fires and saving people, and slowly it has become a saying for firefighting, which is actually to save people.

In the event of a fire, it will be very tolerant of people**, so the main purpose at this time becomes to save people. So it's not called putting out fires.

The word firefighting is actually the abbreviation of saving people and putting out fires, and later it slowly spread to firefighting, which means to save people and put out fires.

I have the same meaning as extinguishing fires, but the ancients said so, and then the times slowly passed down like this.

Can't speak, it's like this, if the fire is small, put out the fire, if the fire is big, extinguish the fire.

The favorable aspect of combustion products for extinguishing the fire is ().

a.Cause poisoning and suffocation of personnel.

b.Flame retardant under certain acuity conditions (correct answer) cAffects line of sight.

d.It has become a factor in the development of the fire and the spread of its branches.

Extinguishing fires with fire can only deal with very large grassland forest fires. When the fire is abnormally large, the air pressure in the center of the fire is very low, and the air pressure on the periphery of the fire is a relative high pressure, causing a strong air flow towards the fire field. At this time, the fire is set on the periphery of the fire, and the fire will be blown towards the fire by the air current, and the combustibles between the fire source and the fire will be burned, and then the fire will be extinguished due to the lack of combustibles.

Fire extinguishing is not about burning oxygen, it's about burning combustibles in advance.

For example, if there is a wind and a gust of wind blows from west to east, should I light the fire on the west side of the sedan car field or on the east side?" Another question is that even if you light the fire, won't the easternmost fire still be blown to the east? Isn't the westernmost fire still being blown in by the wind and oxygen and combustibles?

First of all, you should light a fire on the east side. But it's not that you go and light a fire and sit by and watch it burn, people have to control it. The essence of extinguishing a fire is to make combustibles burn in a human-controlled way before uncontrollable natural combustion.

For example, if you light a fire in the east, you need to prevent the fire in advance in the further east, such as organizing manpower to hold fire extinguishing devices and waiting. In this way, the combustibles in the east are burned out, and the fire cannot spread further east.

Regarding "Isn't the westernmost fire still being blown in by the wind with oxygen and combustibles?" "That's right, while extinguishing the fire, we have to think about not letting the fire spread, so we went to the east and set fires. The combustibles blowing from the west will support continued burning, but will not cause the fire to spread further.

So that we can extinguish the fire in a limited area.