The audio discusses the importance of fire in human civilization, describing it as the most ancient chemical process people have learned to control. The process of combustion is explained, highlighting the difference between complete and incomplete combustion of fuel. Complete combustion of fuel requires a sufficient amount of oxygen, high temperature, and good mixing of hydrocarbons with oxygen, resulting in the release of 8130.7 calories of heat and the formation of carbon dioxide.
The audio also describes two types of furnace systems: forced-air and free gas flow. The Kuznetsov furnace is introduced as an example of the latter, which uses a system of free movement of gases to achieve complete combustion of fuel and efficient heat transfer. The design of the Kuznetsov furnace is explained, including the use of a dry seam, a cap, and a firebox to accumulate and use heat efficiently.
The Kuznetsov furnace is compared to traditional furnaces, highlighting its advantages, including higher efficiency (reaching 93%), reduced smoke, and the ability to install heat exchangers without affecting combustion temperature. The flexibility of the Kuznetsov system allows for the design and building of multifunctional furnaces with various properties and functions.
Here are the key facts extracted from the text:
1. Ordinary air is a mixture of unbound gases, consisting of 78% nitrogen, 21% oxygen, and 1% other gases.
2. The main fuel for stoves is wood, which contains carbon, hydrogen, water, and other substances.
3. When wood is heated, water vapor and gases are released, and it is divided into a volatile part and a solid residue, mainly carbon.
4. The volatile part of the fuel consists of a mixture of carbon and hydrogen, and the process of combustion is called hydrocarbons.
5. The combustion reaction involves the combination of fuel hydrocarbons with oxygen in the air, releasing heat, carbon dioxide, water vapor, nitrogen, and excess air.
6. Ballast gases do not participate in combustion and only heat up due to the heat of combustion of carbon and hydrogen, taking away useful heat.
7. Combustion of fuel can be complete or incomplete, and the main condition for complete combustion is a sufficient amount of oxygen, high temperature in the firebox, and good mixing of hydrocarbons with oxygen.
8. Complete combustion of one kilogram of fuel releases 8130.7 calories of heat and forms one part of carbon dioxide.
9. Incomplete combustion of fuel releases 2428 calories of heat and forms one part of carbon monoxide.
10. The calorific value of fuel with complete and incomplete combustion differs significantly, with complete combustion releasing almost three and a half times more heat.
11. Convection is the process of heat transfer where lower layers of a substance heat up, become lighter, and float up, while upper layers cool down, become heavier, and sink down.
12. Household stoves can be classified according to the mechanism of gas flow movement, including forced-air systems and free gas flow systems.
13. The Kuznetsov furnace uses a cap closed on top and sides to accumulate heat and a dry seam to separate hot and cold gases.
14. The Kuznetsov furnace has a firebox with a grate made of fireclay bricks, which can withstand temperatures up to 1300 degrees Celsius.
15. The Kuznetsov furnace uses a system of free movement of gases, where hot gases pass through a hot fireclay grate catalyst and are almost completely burned, ensuring complete combustion of fuel.
16. The efficiency coefficient is used to evaluate the efficiency of the firebox in furnaces of different systems.
17. The efficiency of the Kuznetsov bell-type furnace reaches 93%, compared to 70-80% for most modern stoves and 30% for traditional stoves.
18. The Kuznetsov stove allows for intensive heating of the room through the walls of the hood, where it is advisable to install heat exchangers of the heating system.