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借助工程信号处理的时域和频域方法，详细分析了竖直管内过冷沸腾中热声振荡特性，获得了热声振荡驻波自激形成与主流过冷度的关系．实验表明，当主流过冷度较大时，过冷沸腾声振荡具有多频性；随着过冷度的下降，多频的声振荡逐渐在管道长度方向上发展为具有单一高频的热声驻波；当过冷度下降到致使加热面接近饱和沸腾时，空泡群脉动所致低频压力波动将取代高频热声振荡驻波．在此基础上，提出了验证热声振荡驻波形成与否的相关判断原则，它可方便地应用于过冷沸腾传热工况的诊断之中．
With the help of time-domain and frequency-domain methods of engineering signal processing, the thermo-acoustic oscillation characteristics of subcooled boiling in vertical tubes are analyzed in detail. The relation between the self-excited formation of thermoacoustic oscillations and the main undercooling is obtained. Experiments show that when the main cooling degree is large, the subcooled boiling sound oscillation has multi-frequency; as the subcooling degree decreases, the multi-frequency sound oscillation gradually develops in the pipe length direction to a single high-frequency thermoacoustic Standing wave; When the degree of undercooling causes the heating surface close to saturation boiling, the low-frequency pressure fluctuation caused by the bubble group pulsation will replace the high frequency thermo-acoustic oscillation standing wave. On this basis, the principle of determining the formation or absence of thermoacoustic oscillation standing wave is proposed, which can be conveniently applied to the diagnosis of subcooled boiling heat transfer.