Experimental investigation on finite-amplitude standing waves: II. Saturation of harmonics in standing wave field

In the process of shock formation, it was found that the tendency to saturation exists for harmonics with the increasing of fundamental sound pressure level (Lpl). When Lpl m and that of fundamental p1 is about pm-p1m. When the fundamental changes 1 dB, the m-th harmonic will increase m dB. The fundamental and all its harmonics start their transition toward saturation at about the same time during the increase of excitation. The relation of pm-p1m tends to pm-p1. The trend of saturation can be divided into three regions in the frequency domain: I. linear region; II. alteration region; and III. shock region. When Lpl>160 dB, the shock is formed. These results are useful for further theoretical work.