Flow pattern map and time–frequency spectrum characteristics of nitrogen–water two-phase flow in small vertical upward noncircular channels

Time–frequency analysis of acoustic and unsteadiness evaluation in effervescent sprays

“…These classic methods had been developed for several decades and successfully applied in various fields. Notably, the AOK method has been proved to be an effective tool for studying time-varying characteristics of gas-liquid two phase flow as for its high frequency resolution and ability to suppress cross-terms (Sun et al, 2011), and it had been well introduced for processing two-phase flow dynamic signal and understanding the dynamical behavior of different flow patterns (Du et al, 2012;Li et al, 2014).…”

The AOK-TFR analysis of high temperature gas–solid two-phase flow

“…In view of strong nonlinear characteristics of the gas-solid two-phase flow, the AOK TFR method, which can show more detailed information of two-phase flow, is suitable for the object of this paper. The adaptive optimal kernel time-frequency representation can be expressed as follows [18]:…”

“…He accurately distinguished the different flow patterns by extracting the two time-frequency characteristic values of total energy and entropy. Li et al [18] presented the result of their timefrequency analysis of small channel gas-liquid two-phase flow. The AOK TFR was utilized to reveal the dynamic characteristic of gas-liquid two-phase flow in a small rectangle channel.…”

Flow pattern map and multi-scale entropy analysis in 3 × 3 rod bundle channel

“…Among they (Chen et al, 2014;Gómez-Hernández et al, 2014;Guilizzoni, 2013;Li et al, 2014;Shaban and Tavoularis, 2014;Zhang et al, 2014). Lee et al (2008) adopted chaotic characteristics of two-phase flow to identify flow pattern and developed a method to identify flow pattern by applying simple classification rules to the density map.…”