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发生在过渡沸腾区的微细化沸腾(MEB)以其极高的换热能力日益受到学者们的关注。本文通过傅里叶变换得到了MEB沸腾音的幅度谱,结合MEB实验中获得的壁温和相应的视频数据,对幅度谱进行了分析。结果表明:通过幅度谱上的特征,可以判别加热面上的沸腾模式。在核态沸腾阶段,沸腾现象较微弱,幅度谱波动不明显。在MEB发展阶段,加热面上存在两类沸腾现象,幅度谱以多峰谱为主要特征。当MEB现象显著发生时,幅度谱300–400 Hz范围内会出现一个MEB特征谱峰。该谱峰的形成与气膜生成和破裂周期存在一定关系,过冷度对气膜变化的周期并没有影响。
The subtle boiling (MEB) occurred in the transitional boiling area has attracted more and more scholars’ attention due to its extremely high heat transfer capacity. In this paper, the amplitude spectrum of MEB boiling sound was obtained by Fourier transform, and the amplitude spectrum was analyzed based on the wall temperature obtained in the MEB experiment and the corresponding video data. The results show that the characteristics of the amplitude spectrum can be used to determine the boiling pattern on the heating surface. In the nucleate boiling stage, the boiling phenomenon is weaker, the amplitude spectrum is not obvious fluctuations. There are two kinds of boiling phenomena on the heating surface during the development of MEB. The amplitude spectrum is mainly characterized by multi-peak spectrum. When the MEB phenomenon occurs significantly, an MEB characteristic peak appears in the range of 300-400 Hz. The formation of this peak has some relations with the formation and rupture period of the gas film. The degree of supercooling has no influence on the period of the gas film change.