People who have air conditioners at home should sing a thanksgiving song, not only thanking the father of air conditioners, but also thanking your family for being able to afford the electricity bill of air conditioners. It is said that in Bangladesh, many people still can't afford air conditioners, so they made such an air conditioner with mineral water bottles and cardboard, which can reduce the temperature by more than 5℃ in a short time, and the production cost is almost zero. It sounds like pie, rice, steamed bread and shredded potatoes in jiaozi. Some netizens are also very skeptical. How can such a thing cool down? How do you use energy when you don't need electricity for cooling?

So in the face of this beautiful thing, we still have to try it ourselves.

According to the tutorial, we should first look for many plastic bottles, which are said to be everywhere in Bangladesh. In Hangzhou, bottles are not allowed to be thrown on the road, so we can only go to the waste collection station to find them.

The requirement for bottles is mainly small mouth and big belly, so a liter of mineral water or coke bottle is more suitable, and the bottle size is best the same, about 50 or 60 bottles is enough. To tell the truth, it's quite hard to do this job on a hot day of 40 degrees. After finding the bottle, find a cardboard, then cut a third of the bottle into a funnel shape and arrange it vertically and horizontally on the cardboard. Then poke holes in the cardboard. Bangladesh version of the simple air conditioning board is a very regular round hole. This is a little simpler. Just poke a few small holes and clip the bottle in. There are 42 bottles on a square meter of cardboard. On that day, the outdoor temperature was about 40℃, so we found a work shed with the doors and windows closed and the temperature inside was 34.4℃.

The first step of the experiment is to remove the window and see if the temperature of separate ventilation is the first point. It's useless ... Ten minutes later, the temperature rose by 0.65438 0℃. Next, stick the simple air conditioner on the window with the bottle mouth inward. From the inside, it is a small hole that is neatly arranged and emits light. Putting your hand near the hole seems to really feel a little cold.

The principle of this air conditioner is said to be "throttling expansion". When the air passes through the bottle, it is under pressure because of the small bottle mouth, and the temperature drops in the process of coming out of the small bottle mouth. This principle is similar to the compressor of air conditioner. In this device, "wind" plays a decisive role. So there is no wind outside, so this thing looks useless, and the temperature in the shed is still very stable. Using an electric fan to simulate the natural wind, blowing it from the outside to the inside of the air conditioner, Dashi sat in the room for fifteen minutes and the whole person collapsed. The temperature hasn't dropped at all, but it's still stuffy and hot.

Therefore, the beautiful "non-power-consuming air conditioner" is in doubt. Rational netizens provided their analysis: if this air conditioner is to be effective, it must be high enough first, and then it must have super wind power. Even in Bangladesh with a savanna climate, there are few weather that meets these conditions.