Abstract:

Based on a self-developed enhanced vapor injection (EVI) air source heat pump, noise source was identified and spectrum analysis was analyzed by the fractional step operation method. The heating performance and noise variation law under variable conditions also were studied. It provides a targeted direction for reducing the noise of heat pump. The results show that the sound pressure level (SPL) of noise is enlarged when the rotating noise frequency of fan is close to the excitation frequency of compressor. When the fan switches from high speed to low speed under partial load, the SPL drops by 6.44 dB. The replenish pressure and inspiratory pressure are increased by EVI, and the SPL at -12℃ is increased by 1.05 dB compared with the gas filling valve closed. The SPL is increased by 2.1 dB when the opening of main valve is 100% compared with 30%. The influence of main valve opening on the noise is greater than that of gas filling valve.

摘要：

以自行开发的一台补气增焓空气源热泵机组为实验对象，通过分步运行法对机组噪声源进行识别和频谱分析，研究变工况下机组供热性能及噪声变化规律，通过对噪声特性和变化规律原因的探究，为针对性地降低机组噪声提供了方向。结果表明：风机旋转噪声频率和压缩机激励频率接近时，噪声声压级会放大；风机在部分负荷工况下从高转速切换到低转速，噪声下降了6.44 dB；补气提高了补气压力和吸气压力，导致管路噪声增大，−12℃环境温度下噪声较补气阀关闭时增加了1.05 dB；主路阀开度100%时噪声声压级较开度30%时增加了2.1 dB，主路膨胀阀开度对噪声的影响大于补气膨胀阀。