Characterization of mist sprays using a phase-doppler analyzer and an iso-kinetic sampling for validation of scale modeling of water mist fire suppression

摘要

A method for quantifying droplet fluxes of a water mist spray uses different measuring apparatuses and compares the measurements of the two apparatuses with one another. One of the measuring apparatuses is an iso-kinetic sampling probe in which the air velocity of the portion of the water spray mist entering the probe is made equal to the air velocity of the water mist spray around the probe by connecting a source of vacuum to the probe. The drops of the spray entering the probe are prevented from passing out of the probe. The air velocity of the spray entering the probe is measured by an anemometer, the drops of the entering spray are collected in a reservoir, and the depth of water in the reservoir is measured by a differential pressure transducer. The output of the pressure transducer is sent to a computer that calculates the water collection rate based on the sectional area of the probe opening and the water collection rate in the reservoir.