Views: 0 Author: Site Editor Publish Time: 2024-11-18 Origin: Site
Summer is here, it's the season of eating barbecue and drinking beer, and we often see diners blowing air conditioners, drinking beer, and feasting on roadside stalls.
I don't know if you have observed, this kind of air conditioning fan that blows out a cool breeze is not the kind of air conditioner installed in our office or home, this kind of air conditioning fan and outdoor spray cooling, and even the ancient "self-rain pavilion" and "cool hall" have the same principle, they actually use evaporative cooling.
Evaporative cooling is a process in which air is cooled by the evaporation of water, i.e., water absorbs the heat of the air and evaporates to cool the air.
The drier the air, the greater its ability to hold water, the greater the reduction in air temperature when spraying the air with water, and the better the cooling effect of the air if the water is used at a lower temperature from tap water or well water.
Therefore, in a high temperature and dry environment, the use of evaporative cooling air conditioning fan to cool the air consumes a lot less electricity than the use of air conditioner, so as to have a good energy-saving effect.
However, the amount of moisture that can be contained in the air is limited (after reaching the limit, adding water will flow out of the air in the form of liquid water), so the temperature of the low-temperature air that can be produced by evaporative cooling is limited by this property, and it is not possible to produce very low-temperature air.
Thousands of years ago, ancient Egypt and Persia used evaporative cooling air conditioners in the form of rooftop wind shafts called "wind catchers". The "wind catcher" is set up against the wind, and the air flows down the wind shaft into the fountain in the building, and then sends cooled air into the room.
In ancient China, there are also records of evaporative cooling air conditioning, the Han Dynasty inventor Ding Xuan invented the seven-wheel fan, "the seven-wheel fan is connected with seven wheels, and most of them are all in diameter ("Xijing Miscellaneous Records" Volume 1)", later generations used water power to drive it and introduced the water flow to the position of air flow, which not only provided power, but also used evaporative cooling to reduce the air temperature, so that people felt that "Ling Ling is selder, not silk and bamboo, and the sky is heard from afar (Qianlong's "Forty Views of the Old Summer Palace)".
Similarly, there are self-rain pavilions, including cool halls, there are poems and clouds "amber red suspected of leaking rain, crystal curtains are more ventilated (Liu Yuxi's "Liu Juma Water Pavilion Summer Retreat")", the cold water is transported to the top, and then flows down from the eaves to form a water curtain, which has the effect of cooling down from the heat.
In ancient times, the use of evaporative cooling principle to escape the heat and cool summer, cool summer is often a service that can only be enjoyed by dignitaries, and now, with the development of society, the air conditioner and multi-online machine used to drive refrigeration have "flown into the ordinary people" family, however, evaporative cooling still has an irreplaceable role.
Evaporative cooling has changed from a very simple ventilation and cooling method to an energy-saving and green technology that uses renewable energy such as dry air, which will effectively promote the realization of "carbon peak and carbon neutrality".
In arid or semi-arid areas in the west, many industrial buildings can completely replace mechanical refrigeration and air conditioning systems with evaporative cooling and cooling air systems, while in humid and semi-humid areas, dew point evaporative cooling can also be used to achieve refrigeration, thereby improving the working environment of the workshop.
In the era of big data, communication equipment rooms and data centers operate uninterrupted throughout the year, and energy consumption continues to increase, while the use of evaporative cooling technology in winter or transitional season, combined with indirect evaporative cooling and pre-cooling in summer, can greatly reduce the annual operating energy consumption.
Evaporative cooling also plays an irreplaceable role in household air conditioning, in addition to the aforementioned air conditioning fans, evaporative cooling can also be combined with new household air conditioning technology.
In the 2021 Global Refrigeration Technology Innovation Awards, the Chinese team proposed an air conditioner scheme of "Advanced Vapor Compression Refrigeration Technology Integrating Evaporative Cooling and Solar Photovoltaic", which organically combines evaporative cooling, solar photovoltaic and high-efficiency refrigeration systems to achieve high efficiency and energy saving of air conditioners and precise control of indoor temperature and humidity, and stood out from more than 2,100 teams to win the championship.
This technology applies evaporative cooling to use dry air as a means of regulating the indoor environment, combined with the ventilation control technology of climate adaptation, to realize the functions of ventilation, cooling and dehumidification, and opens up a new direction for the development of air conditioning technology.
Combining evaporative cooling, a technology with thousands of years of application history, with new technologies, to tap the application value and energy-saving potential of evaporative cooling, so as to contribute more wisdom, solutions and strength to global energy conservation, emission reduction and low-carbon transformation, and inject strong momentum into green development.
