Abstract: At present, the outdoor unit of air conditioning is usually installed in the equipment room of office buildings or high-rise pits, which is close to the user. Excessive operating noise has a direct impact on the user's work and life, and will also cause user complaints and increase the company's operation and maintenance costs. The high aeroacoustics wind noise of the whole machine is one of the main reasons for the high noise of air conditioning operation.Constructs an improved fan-duct coupling method for drag reduction and noise suppression including shape optimization of middle baffle and drag reduction of outlet grills and so on based on the combination of test and simulation, aiming to solve the currently existing problems such as high aerodynamic drag and hyper aerodynamic noises. According to the sample’s air volume and noise experiments reports, the aerodynamic drag and noise of the as-designed machine sample was reduced by 5 Pa and 1.4 dB(A) under the same test conditions, respectively. The optimization analysis results have a certain guiding effect on the efficiency improvement and noise reduction design of the fan duct in the air conditioner outdoor unit.

Key words: Outdoor unit of air conditioner, Fan and air duct, Coupling design, Drag and noise reduction