Diagnostics of transient heat transfer regimes based on statistical and frequency analysis of temperature fluctuations

ABSTRACT The paper presents the results of experimental and theoretical studies of temperature fluctuations at the surface of heaters in different heat transfer regimes. Developing several methods of treatment for the temperature fluctuations, we succeed in the diagnosing the onset of transient boiling regimes. The proposed methods are based on the statistical analysis of histograms and amplitude-frequency analysis of the spectra of temperature fluctuations. In addition, the study demonstrates and compares how these techniques may be utilized to predict the transitions from the convective heat transfer to the nucleate boiling and the film boiling regimes.