【摘要】 本文在低频条件下，用导荧式压力传感器对比性地量测了掺气与不掺气射流作用于水垫塘底部的脉动压强．频谱分析结果表明：射流掺气后，水垫塘底部脉动压强的功率谱变化幅度增大。并随水垫深度的增加而减弱；掺气与不掺气情形，其功率谱没有明显的优势频率，是一白噪声谱；在自相关函数日中，不掺气的Ｒ（ι）～ι关系曲线变化较缓，掺气后变化剧烈，并出现负值；掺气还使时间积分比尺变小，频率增大．更多还原

【Abstract】 This paper investigates characteristics of frequency spectrum of pressure fluctuation on the bottom of the receiving pool plunged by aerated and non-aerated jets by means of tube-pres sure transducer in the low frequency,The results of spectrum analysis indicate that aeration makes power spectrum fluctuate within a broad range. And the spetrum damp with water depth increas iug. There is no clear dominant frequency in the pluning zone. The power spectrum is a white noise. The relation curve of R (ι) ～ι fluctuates slowly for the non-aerated jets, and fluctuates violently for the aerated jet. In addition. aeration makes time integral scales decrease and frequen cy increase.更多还原