FMCG sector HS code analysis

List of contents of this article:

• 1 、Is the aircraft engine better air-cooled or liquid-cooled

Why are most of the engines of Hainan Airlines fighters in World War II air-cooled

1. What the two people upstairs said make sense! ~~But it only talks about the cooling system of the engine (although this is the main one)~~ Engines using a water-cooled system have overlapping cylinders, and there is a protective cover between the engine and the propeller, so the engine cross-section is relatively small and the wind resistance is small. If it is an air cooling system, adding a protective cover is not conducive to heat dissipation.

2. First of all, it can avoid the leakage of coolant and ensure the safety of equipment operation;Secondly, air cooling technology is more suitable in some harsh conditions, such as deserts, because water resources are relatively scarce.

3. Maintainability and damage resistance: Needless to say, the air cooling is good. Even if several cylinders are broken, it will not affect the pilot to fly back.

4. In fact, before World War II, the strongest countries in the world's fighter jet development were the United Kingdom and Germany, which launched the Breathing Fire and ME-109 respectively. These two fighters use liquid-cooled engines. Compared with air-cooled engines, the liquid-cooled engine technology is more advanced. Its size is smaller, and the installation can Reduce wind resistance to the greatest extent.

5. There are mainly two types of star piston engine (air cooling) and V-type engine (water cooling), and there are relatively few other types. Among them, the star type is used more often on aircraft carriers. Air-cooled logistics is much more convenient than water-cooled, which makes the aircraft's combat attendance rate higher.

6. For aircraft with traditional piston engines, there are two modes of liquid cooling and air cooling. As the name implies, liquid cooling is to cool the engine with coolant, and then the heated coolant flows through the metal condit welded with a large number of dense heat sinks to complete the heat exchange between the engine and the external environment.

What is the working principle of the engine cooling system?

The working principle of the engine cooling system: liquid cooling conducts liquid circulation through the pipelines and channels in the engine. When the liquid flows through the high-temperature engine, it absorbs heat and reduces the engine temperature. After the liquid flows through the engine, it flows to the heat exchanger (or radiator), and the heat in the liquid is released into the air through the heat exchanger.

The working principle of the cooling system is to circulate liquid through the pipes and channels in the engine. When the liquid flows through the high-temperature engine, it will absorb heat, thus reducing the temperature of the engine. After the liquid flows through the engine, turn to the heat exchanger (or radiator), and the heat in the liquid is emitted into the air through the heat exchanger.

The main job of the cooling system is to dissipate heat into the air to prevent the engine from overheating, but the cooling system has other important functions.The engine of a car works best at a suitable temperature. If the engine cools down, it will accelerate the wear of parts, thus reducing the efficiency of the engine and emitting more pollutants.

[Working principle] The cooling system of the automobile engine is a forced circulating water cooling system, that is, the pump is used to increase the pressure of the coolant and force the coolant to circulate in the engine. The cooling system is mainly composed of a water pump, a radiator, a cooling fan, a compensation water tank, a thermosulator, a water sleeve in the engine body and cylinder head, and auxiliary devices.

The working principle of the cooling system is the following four points: when the cooling water is forced to circulate the engine, the water pump is driven by the engine. The water pump pressurized the antifreeze and sends it into the waterway of the engine cylinder. Because the pump is in a continuous working state, the antifreeze is continuously squeezed into the cylinder, the water pressure is raised, and the outlet pipe of the radiator is sent through the thermostat.

May I ask whether the piston engine is better, liquid-cooled or air-cooled?

Generally speaking, water-cooled is better. Oil-cooled engines are easy to overheat, and the radiator is relatively large: the specific capacity of oil is too small, and water is in nature. The specific heat capacity is the largest, that is, the water temperature rises by 1 degree to absorb more heat than oil. Oil cooling is usually used in deserts and other places where water is scarce, and cooling oil is relatively expensive and troublesome to maintain.

Air cooling: Advantages: Low cost: Compared with liquid cooling, air cooling has a lower cost, and the installation and maintenance are relatively simple. No additional components are required: When using air cooling, there is no need to add additional water pumps, water tanks and other components, and only it can play its role.

Water cooling is good, air cooling hairThe advantage of the motive is that the structure is simple and does not require additional auxiliary accessories. The heat sink on the cylinder block and cylinder head can meet the basic heat dissipation needs of the engine. However, if the heat dissipation method is too single for continuous driving, the engine will have thermal decay.

Is antifreeze mainly used to cool engine parts?

1. Antifreeze can prevent the coolant from freezing the radiator and freezing the engine cylinder block or cylinder head when parking in the cold winter. The function of antifreeze: Antifreeze is a coolant containing special additives, which is mainly used in the cooling system of liquid-cooled engines. Antifreeze has excellent properties such as anti-freeze in winter, anti-boiling in summer, anti-scaling all year round, anti-corrosion, etc.

2. The engine and cooling system are made of various metals, and the antifreeze has the effect of preventing corrosion of metal parts and rust removal.If replaced with water, the cooling system and engine will be corroded or rusted after a long time of contact. Anti-scale. Antifreeze has an appropriate amount of anti-scale agent, which can inhibit the generation of scale. Anti-freeze.

3. Automobile antifreeze is mainly used in the cooling system of liquid-cooled engines, which has excellent properties such as anti-freeze, anti-boiling in summer, anti-scale, anti-corrosion, etc. The specific functions of automobile antifreeze are as follows: cooling effect Automobile antifreeze is also known as coolant. As the name implies, it is used for cooling, which is also the basic function.

4. Antifreeze is a coolant containing special additives, which is mainly used in liquid-cooled engine cooling systems. Antifreeze has excellent properties such as antifreeze in winter, anti-boiling in summer, anti-scale, anti-corrosion and so on.

Is the aircraft engine better air-cooled or liquid-cooled?

Although Mercedes-Benz's DB601 series is perfect, the advantages and disadvantages of the liquid-cooled engine and the air-cooled engine are very clear. As a front-line combat fighter, the liquid-cooled engine is used for ground maintenance and loss resistance. It has obvious disadvantages.

Second, the air-cooled engine is more suitable for combat in cold regions. Liquid cooling needs to replace the special coolant to prevent freezing in the cold area, and when the liquid cooling engine is operating in the cold area, it needs to be warmed for a longer time before starting. Third, the damage resistance of liquid cooling is also slightly inferior. Air-cooled engines are generally arranged in a star shape, and each cylinder works independently.

For aircraft with traditional piston engines, there are two modes of liquid cooling and air cooling. As the name implies, liquid cooling is to use cold.But the liquid cools the engine, and then the heated coolant flows through the metal conduit welded with a large number of dense heat sinks to complete the heat exchange between the engine and the external environment.

Beso, if you can aim at the heat dissipation system, it is not more effective to hit the cockpit. This is part of the reason why the P-51 with poor damage resistance can replace the more damage-resistant P-47. Besides, for land aviation, coolant is not a problem.