DISCRETE WAVELETS TRANSFORM ANALYSIS IN AXIAL VELOCITY DISTRIBUTION OF SPIRAL FLOW

摘要

Time-frequency distributions of axial turbulence velocities of spiral pipe flow and typical turbulence flow have been clearly decomposed in a range from low frequency level to high frequency level by means of discrete wavelets transform. As a result, the lower frequency levels (under Level 4) of the spiral flow are extremely lower as compared with those of the typical turbulence flow. Moreover, the spiral flow is dominated by Level 3 to be stabilized from the autocorrelation. The originality of this paper lies in applying discrete wavelets transform and its autocorrelation analysis to analyzing the spiral flow stable motion in time-frequency dimension.