Starting in 2023, all gas stations in China have completed the switch of "China VI B" gasoline and diesel.
So as long as it is the owner of the car who refueled after January 2, your fuel tank is properly filled with "China VI B" gasoline. The level of gasoline has been raised, which would have been a good thing. But unexpectedly, the majority of car owners and friends have said: since the use of "National Six B" gasoline, strange things have happened one after another.
After using "China VI B" gasoline, poor power, high fuel consumption, and wild water spray?
It is said that the gasoline power of "China VI B" has become weak, and the car has become meaty; It is said that the consumption of "China VI B" gasoline is higher than that of the previous "China VI A" gasoline ... But to say the most evil of them, that is, there are many people who say that "China VI B" gasoline causes the exhaust pipe of the car to spray water - online self-media has released a lot of videos.
So the question arises: what is this "China VI B" gasoline? Why do it cause so many problems, especially the things that cause the exhaust pipe to spray water? ——Today I will talk about this matter to see if the "National VI B" gasoline is tricky, or there are some other hidden reasons.
Car exhaust pipes do run water
First of all, friends who are familiar with the principle of automobile engines are clear: the better the combustion state of the engine, the more "clean and thorough" the combustion, the more water vapor in the exhaust. Then the water vapor meets the cold steel (exhaust pipe), and naturally condenses into water droplets. Water droplets accumulate in the exhaust muffler, and finally the exhaust muffler becomes a "pool".
As long as the car accelerates or drives uphill, the stagnant water in the exhaust silencer will be blown out by the exhaust fumes when shaken. Finally, it is sprayed out of the nozzle of the exhaust pipe and scattered on the road. - This is the whole process of water spraying from the exhaust pipe. So why have we found that many cars have recently sprayed water on their exhaust pipes, but they didn't notice much before?
You think, water vapor is originally "condensed in case of cold" (the principle is the same as air conditioning dripping), so you will find a rule: you can hardly see the exhaust pipe spray in summer, and often see it in winter, this is the truth. In addition, after the car has driven a distance at high speed, the exhaust pipe no longer sprays water. - This is because the exhaust pipe is hot enough, so condensation no longer occurs, and the stagnant water in the silencer cylinder is also blown away.
What is the change in "China VI B" gasoline?
With or without ethanol? How high is the content?
Returning to the "China VI B" gasoline itself, the official statement is clear: compared with the previous "China VI A" gasoline, the olefin content has been reduced from 18% to 15%, the amount of MBTE antiknock agent has been slightly increased, and the amount of alkylated oil (which is a good thing) has been slightly increased. Other chemical composition indicators have not changed at all.
Even the upstream refineries themselves have said: the smelting process and process of "China VI B" gasoline and diesel are almost unchanged compared with the old "China VI A" gasoline and diesel (just the refinement of indicators). Measured in the laboratory, the difference in calorific value between "China VI B" gasoline and the old "China VI A" gasoline is almost negligible.
And about the "China VI B" gasoline, the amount of ethanol added, we also inquired about the corresponding specifications. Because of the previous online rumors that "China VI B gasoline, the ethanol content will increase to 15%". However, the truth is: in the regular "China VI B" gasoline, the ethanol content requirement is 10% (±2% error), which is exactly the same as before, and has not changed.
And the official explanation is also very clear: your local "ordinary gasoline" is still "ordinary gasoline" (it does not contain ethanol); The "ethanol gasoline" used in your local area is still "ethanol gasoline" (the ethanol content is still 10%).
Add "China VI B" to spray water? The reason has been found!
Therefore, according to this, the car uses "National VI B" gasoline, and there should be no "poor power and high fuel consumption" situation. Assuming that at this time of the previous year, the temperature and road congestion were basically the same as now, it should be this time of the previous year, what fuel consumption and power performance were like, and what it is still now.
As for the water spray in the exhaust pipe, the "National VI B" gasoline is purer, theoretically more complete and more complete combustion, and the water vapor produced by combustion will be slightly more. Therefore, on the road surface in winter, the white water vapor spewed out by the exhaust pipe of the vehicle will be more obvious, and the water sprayed from the exhaust pipe will be slightly more.
But this "more" is only relative, only slightly more. It is impossible that at this time last year, the exhaust pipe did not spray water, and after changing the "China VI B" gasoline, this month began to spray water wildly. ——If there really is such a thing, then we must wonder if the vehicle has added some "problem gasoline", or the video author has made some small action to gain attention.
Sure enough, some people on the Internet claimed that they deliberately flushed water into the exhaust pipe, and then filmed a video saying that "I sprayed water because I added China VI B gasoline", and the purpose was to gain attention and earn traffic. Seeing this, I think you can understand the principle of "car water spraying" on short video websites
Write at the end
Dahu Yu is a science and engineering man, and my habit is: use the various principles and laws I have learned to give various possible hypotheses, and then combine the corresponding data to verify my hypotheses. So as to find the most likely answer. In a word, science and engineering men are hardly influenced by the so-called "conspiracy theory" to their objective judgment of things.