Research on Heat Dissipation Performance and Long-term Reliability of the Flapping Wing Cooling Technology Applied to the 5G Communications Equipment

To further improve the heat dissipation efficiency of the 5G communications equipment, this study innovatively applies the flapping wing cooling technology to outdoor 5G base stations. A series of experimental and numerical studies have been conducted to explore effects of the flapping wing cooling device on heat dissipation performance and long-term reliability of 5G communications devices. Specifically, (1) Taguchi method was used to determine geometric parameters (length, width and spacing) of the flapping wing cooling device’s blades, where airflow and noise were objective functions of the optimization method; (2) additionally, Computational Fluid Dynamics simulation and thermal tests were conducted to demonstrate advantages of forced convection compared to natural convection. The results indicate that: (1) when blades of the flapping wing cooling device are 15 mm in width, 70 mm in length, 14 mm in spacing, the airflow reaches the maximum of 10.7 CFM, with the noise level meeting the permissible noise standard of the 5G outdoor devices; (2) the flapping wing cooling device reduces the temperature of electronic components of the 5G AAU by about 10 °C on average. The temperature drop of electronic components near the fan outlet is 6 °C higher than that of electronic components 0.5 m away from the fan outlet. In terms of reliability, Finite Element Method simulation was conducted to research the failure probability of the flapping wing cooling device under vibration fatigue; besides, based on a series of environmental durability tests, the reliability of the flapping wing cooling device for long-term usage outdoors was explored. The results show that: (1) the maximal Mises stress of blades is lower than fatigue limit of its own materials, and vibration fatigue life meets the requirement of 10 years; (2) the flapping wing cooling device has passed high temperature aging test, temperature cycling test, high temperature and high humidity aging test, salt spray test, demonstrating the feasibility of long-term outdoor operation. In conclusion, the flapping wing cooling device can effectively reduce the size and weight of the 5G communications devices by improving the heat dissipation efficiency, which is a great breakthrough in enhancing the competitiveness of products, and what is more, it is reliable to operate outdoors for a long time.