Haze is composed of small solid particles and droplets

To see such an extreme topic and such a sad map, most of the reader's first reaction is, "Is this Kryptonian mad by fog?" ”

So I have to defend myself, though my rhinitis has been cornered by the smog of Beijing, but it is still sane. The title of this rigorous and objective expression is, "I personally think that under the existing technology level, for the residents of northern China, most of the air purifiers are paper tigers, all desktop-level air purifiers are bullying." "As for why, listen to me carefully."

Let me first say why most air purifiers are paper tigers. At random in an electric business platform search "Air purifier", the result is nothing more than sharp, Panasonic, 3M so several brands. In short, most of them come from the United States and Japan. Admittedly, this is the two technology giants, but why should I say that they are mostly paper tigers? Very simply, which eye did you see the haze of Japan and America?

In fact, air purifiers in the United States and Japan are designed to prevent pollen allergies and secondhand smoke, which is based on the assumption that outdoor air is clean. But in fact we know that the air outside our window is clean. And the haze is made up of solid particles and small droplets, and the obvious fact is that the air density outside the window is larger than the inside, so the air inside the window will spread to the house, which is a challenge to the air purifier.

Of course, some people would say that the Japanese and American air purifiers can also be adapted to the situation in China. But in fact, this kind of adjustment needs in the turbine design, the gas chamber design, the pattern design and so on many aspects, but I have not seen the related enterprise in this aspect the effort at present. Of course, there may be such a purifier, but the popularity is too low, let me through a variety of channels can not find, or the price is too high, so that even the courage to see not.

Then let's talk about why "all desktop-level air purifiers are bullying".

The country's poor air quality has led many small entrepreneurial teams to see the concept of "desktop-level intelligent air purifier" feasible and rushing into the field. Basically they all have three characteristics: one is small, can be placed on the desktop, and "to ensure the quality of the air near the body"; second, multilayer adsorption, there are generally 3 layers of filter adsorption of different aerosols and harmful gases; Three is the air quality detector, and connect the cloud, using "large data" intelligent learning and predicting air quality, Open automatically when the air quality becomes worse.

And do not spit "big data" why can tell us which day haze, when someone in the room smoking these factors that affect air quality, desktop-level air quality purifier is based on "maintaining the air quality near the human body at a better level" this concept is worth pondering. We can imagine a little: the current desktop-level air purifiers are used passive adsorption, that is, let the air through the multilayer filter, and then the new air from the vent in the mouth of this way to purify the air. Even if the vortex caused by the air is not considered to allow the "two" air to quickly mix, consider the gas Brownian motion and the Law of gas diffusion, we can also know that the two "air" because of the density of the difference caused by the pressure difference will allow them to quickly mix. "The air around the body" is not in this environment alone into a pure land.

Okay, is that a desktop-level air purifier that can purify a room's air? Yes, but let's do a little calculation: Suppose I sit in an office that is 10 meters long, 10 meters wide and 3 meters high, and my room will hold 300 cubic meters of air. If the air purifier of the desktop level is 100 square centimeters, then assuming that all the air in the room will pass through the air purifier in half an hour, the wind speed of the inlet will need to reach 60 km/h. Is this driving a car?

Of course, we can reduce the volume of the room, increase the air inlet area, so that the wind speed to reach the acceptable 1 kilometers per hour (if in a very small room). But here's the question, how much noise does a small, desktop-level turbine provide at this speed? The size of the noise depends on the design of the turbine and the air chamber, and there is no general formula to express it, but from a personal experience, the small air purifier I've seen has a very loud noise.

Therefore, we can see that the air purifier is not a lot of people think to buy some filters, all the fans, put a motor, outside the shell so simple. Really want to do air purifiers actually have a high technical threshold.

In general, the current market of the air purifier relatively large problem or technical bottlenecks: How to redesign the wind chamber and turbine to let wind speed and reduce noise to achieve balance? How many litres of air per hour are appropriate in the foggy city of Beijing? What is the solution when air convection occurs?

Of course, there is currently not only passive adsorption of this air quality solution, but other existing air quality programs generally produce harmful to the human body ozone, can only purify specific solid particles or gas problems. It also makes me wonder whether the recent air quality testing equipment and small purifier are all just a blip in the bubble?

Does that mean air purifiers are unreliable? Not so. My view is that the reliable air purifier is not not, or may exist, just need to take into account the reality, quiet down to do research and development, rather than blindly hype concept, while the public attention to the air quality of the opportunity to heat up the big cashing. In this respect, the domestic hardware manufacturing industry has enough advantages, if really willing to do, I believe that the air purifier suitable for China should be made by the Chinese team.

Therefore, to be determined to do the air purifier start-up team, I can only say, "efforts to do research and development, but cherish the line." ”