Measurement of Micro-Scale Flow Structure in a Circulating Fluidized Bed

摘要

A Phase-Doppler Particle Analyzer (PDPA) has been applied for studying the local instantaneous flow structure in a two-dimensional circulating fluidized bed. Based on the PDPA measurements of instantaneous particle velocity, particle size, and the time for crossing the measurement volume, a method of determining local bed voidage in dilute particle-fluid suspensions is proposed. Measurements were performed simultaneously with the PDPA system and an optic fiber probe at the same flow conditions, showing that the PDPA measurement can observe the detail structure in dilute suspensions which however is not detectable by optic fiber probes.