What are the technical trends in the development of cooling towers?

High heat transfer efficiency, empty tower. Corrosion-resistant. Low cost. Not from this major. . .

Development trends in cooling tower technology: (1) Environmentally friendly cooling towers. With the progress of human civilization, environmental protection has been given great importance. Cooling towers release large amounts of steam into the atmosphere, causing thermal pollution in the surrounding environment; moreover, the white steam is visually uncomfortable for people. Finding a way to achieve water cooling without white steam contamination has become one of the development trends in modern cooling tower technology. Currently, cooling towers free from white steam pollution have been developed in Europe and the United States, but they are expensive. This type of cooling tower is divided into a dry cooling section and a wet cooling section. Hot water first enters the dry cooling section, which consists of finned tubes, and then proceeds to the wet cooling section, where it exchanges heat with cold air. The cold air, once heated, exits the packing area along with the humid steam; it then mixes with the dry hot air in the dry cooling section, resulting in a significant reduction in its relative humidity. In this way, the hot air sent into the atmosphere by the fan is no longer in the form of white misty vapor. At present, no such cooling tower has been introduced in the domestic market. (2) Low-noise cooling towers: How to further reduce the noise pollution caused by cooling towers to the surrounding environment is also one of the areas of research. The noise in cooling towers is mainly caused by water droplets falling onto the water surface at the air inlet of the fan motor. To reduce the noise generated by the fan, it is necessary to lower the speed of the fan blades (the tip speed), but this affects the air volume and air pressure, especially the air pressure (which decreases in a quadratic relationship with the speed). Therefore, there is much work to be done in developing fans with better performance and lower noise, as well as in designing new blade shapes. To eliminate the noise generated by water droplets, one can start by selecting and developing better sound-absorbing materials and methods. (3) High-efficiency, low-energy cooling towers: Research is being conducted on fillers with larger heat transfer surface areas, in order to remove more latent heat of vaporization using the smallest possible volume of filler and minimal air flow. This requires extensive experimental research; generally, the higher the efficiency of the filler, the greater the requirements for the filler molds and shaping machinery. The general manufacturing process for plastic fillers is: plastic pellets → plastic sheet base → heating → mechanical shaping. Currently, advanced manufacturing fillers have eliminated the need for a plastic sheet base in the production process; it involves only two steps: plastic particles followed by heating and mechanical shaping. However, this requires very high standards for the equipment used for heating and mechanical shaping. The gap in this area domestically is quite significant, and efforts are needed to catch up. In addition, efficient cooling tower fans and operating control systems for cooling towers have been developed to ensure the proper operation of the system more effectively, and to automatically adjust the cooling tower to the most economical operating mode based on different process parameters. (4) Computer-aided design for cooling towers: In developed countries, the design of cooling towers is entirely computerized. What used to take days to accomplish through manual thermal calculations can now be done in just 10 minutes using computer-aided design. Moreover, the accuracy of the design values compared to actual measurement results is quite high (over 95%). There has been no significant progress in domestic cooling tower design in this regard.