Abstract: Compressor is the main noise source of refrigeration system. At present, most of the compressors are wrapped with multi-layer sound insulation cotton to achieve the purpose of noise reduction and sound insulation. By studing the sound insulation law of different thickness of PVC and non-woven fiber. Then, different thickness of PVC and non-woven fiber are combined by bonding to study the sound insulation characteristics of the two-layer composite structure. Through the method of multi parameter nonlinear regression, the virtual digital sound insulation prediction model is established. The model can provide a fast selection method for practical application.

Key words: Double layer composite, Sound insulation characteristics, Nonlinear regression, Prediction model