Investigation of Slug Flow in Microchannel Boiling by Impedimetric Sensing

Abstract

In this work, the possibility of using an AD5933 chip in an impedance logging system to monitor two-phase flow boiling in microchannels is investigated. Microchannel boiling flow regimes include bubbly, annular, churn, and slug flow. We have investigated the application of local impedance sensors to monitor boiling flow, specifically in the slug regime, as a demonstration case of the sensing concept. The logged impedance amplitude data from the AD5933 were validated by synchronized high-speed videos. Further post processing analysis of the results represents a great potential in using impedance sensing information on microchannel boiling by obtaining critical local information about the flow such as slug pulse width, slug frequency, and duty cycle.