How long does it take for the train to warm up in place?

In fact, the current car does not need the preheating process remembered by the old driver. As soon as the engine is started, a series of strategies should be taken to heat up as soon as possible. For example, in the first 30 seconds after the Volkswagen cold start, the computer will control not to let the coolant flow through the engine, so as to achieve the purpose of rapid warm-up.

So we don't have to go to the so-called "in-situ hot car", get off and smoke, rub our hands and stamp our feet. It is completely unnecessary, because strictly speaking, it is better to "heat for a few seconds".

After the engine stops, the oil slowly flows back to the oil pan from the friction surfaces of the internal parts of the engine. When restarting, it needs to be pumped to the surface of each component by oil pump.

At present, the engine is badly worn, which is equivalent to dry grinding, right? There is not much lubricating oil. To reduce the engine load as much as possible, it is best to wait in place for a short time, but this process is very short.

Peng Gaohong has a paper in the magazine Highway and Automobile Transportation, which summarizes the research on pre-lubrication technology of automobile engine starting. It says that he specializes in this. This is related to the engine temperature, the characteristics of the battery and the starting system, and it takes about 10 to 30s. Generally speaking, with the current technology, 10 second is enough.

Here we go. Look in the mirror and see if there is anything wrong. Navigation position has been set. 10s is over, so there is no feeling of hot car in place. Actually, 10 has been closed for you.

How long will the whole process take?

As for how long it takes for the whole vehicle to warm up, it depends on the temperature. The main purpose of warming up the car is to raise the temperature inside the engine, including the in-cylinder temperature, coolant temperature and engine oil temperature ... Just like an athlete, he has to warm up and open the ligament before the game. The specific warm-up time also depends on the individual's physique. Is the joint or ligament really open?

Wu of xihua university has a paper "Research on the Test Method of Cold Start Performance of Automotive Gasoline Engine". It says: In the cold start test, hot car is defined as the process of engine water temperature rising to 80℃.

It can also be said that the warm-up process is over when the engine water temperature reaches about 80℃. Listen to the paper "Experimental Study on Water Temperature Correction Strategy of Engine Thermal Management" published by Yan Shuanghe and others in the Journal of Internal Combustion Engine and Accessories.

It says: An experiment was made with a 6-emission 2.0L inline 4-cylinder supercharged direct injection gasoline engine in a country. The results are as follows: If the engine has no thermal management module, it takes 320 s for the water temperature to rise from normal temperature to 80℃; When the engine has a thermal management module, this time will drop to 200s, with a difference of 2 minutes.

Nowadays, newer cars generally have this kind of thermal management module, which can automatically control the size, circulation and flow of coolant. The mass technology mentioned at the beginning also falls into this category. Judging from the test data, it is generally enough to control the hot car time at about 3.5 minutes. If it is an old car, consider extending it to 5.5 minutes.

Winter 10s or so is enough.

Generally speaking, a cold start in winter really needs a hot car. The local hot car is about 10s. After the oil flows to the surface of the internal parts of the engine, you can start the car and heat it while driving.

In the meantime, be careful not to leave the basement, and the "high-spirited" people will come after three or four thousand turns. After waiting for about three and a half minutes, the water temperature rises to about 80℃, and the hot car process is over. Is it okay to drive like this again? That's three or five minutes.