On the Hacker News forum, some curious people ask: if the room temperature is assumed to be 30 degrees Celsius, the outside temperature is about 20 degrees Celsius, would it be more reasonable to put inward or outward fan fans? Capturing the main spirit of the question, seeing the urgency of the answer, the Quartz reporters went to find the truth.
In this case, it must be assumed that using a fan is more comfortable for people sitting in the room, because the purpose of putting fans on Hacker News is completely different – to keep electronic devices in the room running smoothly. At 30 degrees Celsius and with dry air, there is a high probability that a person will sweat. This is the way heat is released that evolution has given people: the method of "saline liquid leakage to reduce body temperature quickly" is the most effective air-conditioning mechanism on the planet.
But in the days of mechanics and technology, we have energy-consuming objects to make people's lives more comfortable, not to sweating to cool down. The simplest is an electric fan.
In this case, you will want the air in the room to cool to you. The feeling of wind blowing on the body makes people more comfortable, said engineer Andrew Persily, room temperature research specialist for the National Institute of Standards and Technology.
When sweat evaporates into the air, it carries the amount of heat that is in our body. Even if you don't sweat enough to wet your shirt, your body always releases a certain amount of moisture, keeping your body balanced at all times. Any type of wind that blows through your soft skin – the wind fan, the air conditioner or the wind – speeds up the heat of the body, thereby making you cooler.
According to Persily, the wind is still cool: if the wind speed is too high, you will only feel uncomfortable.
Meme 10 years ago: "He must be famous, many 'fans' are like that."
So put the fan in or out?
The fan blows the wind in a certain direction, drawing air from behind and pushing it forward. According to Persily, fans can be considered to reduce room temperature by eliminating heat. However, the reduction of heat can only occur if the room is hot in connection with a lower temperature space. By drawing hot air from the room, low air pressure will pull the air from anywhere possible; Assuming that the room temperature is lower than the room temperature, the cool air outside will flow into the room, but most of the fan exhaust will be from the next room (because the exhaust fan by the engine is concerned What to air pressure).
Besides, the fan is an electrical device so it will generate heat when operating. If the power supply for the fan is inside the room (electric fan or electrical outlet in the room), the heat will make the room a little hotter, insignificant and difficult to recognize, but still available.
In conclusion, in this case, the best way to cool the room down is to open the door and point the fan inside. The cold air from the outside going into the room will blow up your hot body, to speed up the heat.
Gone With the Wind, with Clark Gable playing Rhett and Vivien Leigh as Scarlett.
How to optimize the fan during hot summer days
Change the scene a bit, but in the current weather, the room is as hot as the outdoor, so this will be the most easy-to-contact situation. In this case, the room temperature is likely to be lower than the outside. Another assumption is that we find ways to keep the body temperature not too high, the most important point is how the wind is blowing, which will help sweat evaporate the fastest.
If the outside is windy, opening the door will bring in a new wind and will help us cool. However, no one anticipates the wind and sometimes you let cool air in the room escape. One way to maintain a steady flow of air is to incorporate fan conditioning: to bring cold air from room A – conditioned to room B – hot, leave the fan in the door between the two rooms and put the fan in. B. room this is obviously very, but just say enough.
If there is no air conditioner, the best way is to close all the doors and turn the fan straight on the person.
Game that everyone has definitely tried: say a fan.
"Fans did not make the room cooler; It cools your body temperature thanks to its ability to create airflow"Persily said. And pay special attention, because they don't cool the room, never turn on the fan to "give it a room" and then leave the other room, because the heat from the fan motor just heats the room, but it also costs electricity.
There is another important factor when lowering body temperature: temperature is not all, sometimes you need a bit of air movement.