88. Noise control and sound quality evaluation of outdoor unit of split air-conditioner

Chengjun Wu1, Xiaofei Lei2

School of Mechanical Engineering, Xiían Jiaotong University, Xiían, P. R. China

2Corresponding author

E-mail: 1chengjunwu68@163.com, 2xiaofeilei86@163.com

(Received 17 February 2016; received in revised form 7 June 2016; accepted 16 June 2016)

Abstract. Low-noise, energy-saving and improved sound quality has been the major concern for the eco-design of household appliance product. In this paper, taking off from vibro‑acoustic coupling, a composite noise control scheme (CNCS) combined with dynamic vibration absorbing technology, the sound absorption technique, controlling noise in the outlet, and particle damping technique is developed to control the sound radiation from an outdoor unit of a split air‑conditioner based on sound sources identification. With the help of developed experiment platform, application effect of each technology and CNCS are measured, experimental evaluation shows that the developed CNCS can reduce the sound pressure level (SPL) more than 10 dB. To clarify the application effect of CNCS in sound quality further, it should be evaluated subjectively by using experiments. Experimental result shows that the stability and smoothness of the unitís noise have been greatly improved in time domain signal of sound pressure, the fluctuation strength is greatly improved for the controlled unit, the value at the left ear is reduced from 0.0195 vacil to 0.0146 vacil, and the right ear value is 0.0141 vacil instead of 0.0251 vacil. In addition, the sharpness has also been significantly reduced after CNCS, the value at the left ear decreases from 2.11 acum to 1.97 acum, and 2.01 acum to 1.86 acum for the right ear. So, CNCS is a pragmatic technique to control noise, vibration and improving sound quality.

Keywords: split air-conditioner, outdoor unit, noise control, sound quality evaluation, sound radiation.

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Cite this article

Wu Chengjun, Lei Xiaofei Noise control and sound quality evaluation of outdoor unit of split air‑conditioner. Journal of Measurements in Engineering, Vol. 4, Issue 2, 2016, p. 58‑69.

 

Journal of Measurements in Engineering. June 2016, Volume 4, Issue 2

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