Chapter eight hundred and forty-eight air cooling and water cooling
The engine is a contradiction.
When working, the engine requires a certain amount of heat. For example, the cylinder can only complete a perfect combustion with a certain amount of heat, and the press-ignition diesel engine requires a very high temperature.
However, high temperatures will cause problems to other devices. Take the most basic cylinders and pistons for example. High temperatures will expand, and after expansion, it will cause the pistons and cylinders to get stuck. Continuing to move is to pull the cylinder. As long as the engine is high,
Pulling the tank is 100% something that will happen.
What if the gap created at the beginning is larger? When the temperature is not enough, it will lead to insufficient air tightness. The air and fuel inside the cylinder will pass through the sealing ring on the piston, enter the bottom, and flow into the engine oil shell.
The ending is the increase in engine oil.
The engine needs a certain amount of heat dissipation, and this heat dissipation was initially air-cooled.
Just like on the engine of a motorcycle, there are a large number of radiators on the cylinder wall and cylinder head. During the engine operation, the heat is emitted through these radiator-like radiators, and the power of the wind is used.
To cool it is called air cooling.
When the motorcycle starts, there will be wind, and when it stops, it will run at high speed for a long time, and the cylinder will inevitably be pulled.
Air-cooling has been mainstream for a long time because of its simple structure.
The current Deutz diesel engine is also air-cooled. Although nothing can be seen from the outside, the huge fan in front actively blows a lot of air into the inside. The internal cylinders are all equipped with heat sinks, so this will force the
cool down.
During World War II, it can be said that air-cooled and water-cooled engines coexist. Many cars also used air-cooled engines, but after that, more and more vehicles began to use water-cooled.
As the so-called water cooling, there is no heat sink outside the engine, but a water jacket. The water jacket is already made when casting the cylinder. When the engine is running, water is circulating and constantly taking away heat.
Then the water evaporates the heat through the radiating water tank in front of the engine.
Compared with air-cooling, water-cooling devices are obviously more complex, so at the beginning, air-cooling dominated the mainstream, after all, but now water-cooling has long occupied an absolute dominant position.
Mia looked at Qin Zhenhua unmoved and continued to introduce it: "You can see that the engines on the civilian market are all water-cooled and air-cooled engines are already considered outdated and eliminated products, after all
, It has many shortcomings that cannot be overcome, while the shortcomings of water cooling are gradually overcome."
"I know." Qin Zhenhua said: "The air-cooling heat dissipation method is not as good as water cooling, and the heat dissipation is uneven and the temperature is not easy to control. If you want the engine to work better at a certain temperature, the engine's efficiency will be maximized.
Optimization, you must use water cooling.”
Air cooling depends on the flow of air, which has many restrictions. For example, in summer, in the desert area, the air outside is hot enough. Let it dissipate heat to the engine, and of course the efficiency will be low.
At the same time, no matter how the air-cooling dissipates heat, the contact area will never be as good as water-cooling, so it is inefficient. Especially after turbocharger, it is even more difficult to dissipate heat by air-cooling.
At the same time, air-cooled heat dissipation depends on the outside situation. It is difficult for you to control it. The speed of the car is fast and the temperature outside is low, so the heat dissipation is strong. Otherwise, it is weak. If the engine temperature cannot be accurately controlled, it is not conducive to the precise combustion of the engine.
Moreover, air cooling requires a large distance between the cylinders so that they do not interfere with each other. Without the wrapping of water jackets and other components, all the noise inside is transmitted, resulting in a lot of noise.
These are all the disadvantages of air cooling.
"Yes." Mia said on the side: "Now, various engine factories are developing new coolant, which can not freeze at low temperatures and have a higher boiling point than water. In the future, water-cooled engines have already
There is no need to add water every day, so you don’t have to worry about cooling water at all. Even in severe cold weather, it will start like the air-cooling.”
The most complicated problem of water cooling is that you have to let go of water in winter. When starting, you have to heat up the water first, which brings a lot of operational inconvenience. However, with the development of special coolant, these weaknesses will also be
Be overcome.
It will not freeze even at minus forty degrees Celsius, so you don’t need to put it in winter. At the same time, the boiling point exceeds 110 degrees Celsius, which can completely keep the engine’s normal working temperature at about 100 degrees Celsius. When the temperature is high, the engine’s thermal efficiency will also be
improve.
In this way, the driver does not have to worry about coolant at all, and it is as convenient as air cooling.
"I know all of these." Qin Zhenhua said: "But I just like air-cooled engines."
"You!" Mia felt that all the words she had just said were in vain, and she wanted to stamp her feet. Isn't this treating other people's kindness as a donkey's liver and lungs?
I even like you, do you still learn from other people's coquettish girls when you are so old?
Qin Zhenhua smiled and said nothing else.
That's right, he naturally knows these shortcomings of air-cooled engines, but do you choose them now?
When their first-machine factory produces Mercedes-Benz cars, they are destined not to be used only for civilian purposes, but more on the military market. The army has a special preference for air-cooled engines. If it is fought, it will cool down.
What's the system broken?
There was such an example in World War II. In the aircraft engine, the water-cooled engine, as long as the cooling system is hit and the coolant is leaked, the engine will soon be unable to work, but the air-cooled engine is different, and it is broken.
Two cylinders, the others can still work normally.
At the same time, the maximum power of Steyr's WD615 engine that is now introduced is only more than 300 horsepower. If the Deutz engine can be continued, the maximum power can reach more than 500 horsepower.
Of course, I am not just for cars. At that time, all kinds of armored vehicles can be used! The larger the power reserve, the better, this is an eternal truth.
After all, the first aircraft factory is now busy improving the potential of its own tank engines. In other aspects, it is indeed not enough to care about it, and can only rely on other brother factories.
As for Mia, in addition to her friend's position, she believes that the air-cooled engine has declined, there is no need to continue to invest more in this regard, but on the other hand, isn't she considering Mercedes-Benz? If the Deutz engine is not
If they pass the qualification, they can export more original Mercedes-Benz engines.
Although I can't judge a gentleman like this by the villain's heart, wouldn't I be too naive if I don't even consider Mia's position?