The paper presents gamma absorption method applied to a two-phase flow evaluation by advanced statistical analysis of recorded stochastic signals. Two selected methods based on the cross-correlation function and phase of the cross-spectral density distributions are considered. Cited examples illustrate application of specified functions to measurement of velocity of gas phase transported by water in a horizontal pipe. Moreover the uncertainties of velocity measurements using the both statistical methods were calculated and compared.
Keywords: two phase flow measurement, radioisotopes, sealed sources method, cross-correlation, phase of cross-spectral density function