Investigation of fire extinguishment mechanisms at microscopic level

This study is aimed at investigating the microscopic behaviour of water droplets in fire extinguishment mechanisms. In particular, this study focuses on the qualitative and quantitative measurements of a water droplet interaction with smoke particles and solid fuel surfaces in a fire scenario. The main topics of this research are focused on fundamental small-scale processes by utilising various imaging techniques to study the static and dynamic behaviour of water droplet evaporation. The evaporation characteristics of water spray can be studied at a fundamental level by examining water droplet evaporation. Evaporation, vapour formation, liquid phase dynamics, and interactions of water droplets share similar processes with droplets in spray systems. Therefore, isolated droplet studies which involve energy transfer and mass transport are relevant to the complex environment of spray in fire extinguishment applications. Image processing techniques were used in droplet evaporation, surface evaluation, and impact studies were outlined. Calibration of thermal cameras in different infrared bands was performed. Using synchronised technologies at the same time made it possible to acquire evaporation characteristics simultaneously and study interactions comprehensively. The investigated interaction between droplets and combustible surfaces shows the importance of microscopic behaviour in assessing the fate of combustion processes. This fundamental understanding paves the road for improved fire dynamics models and better technological approaches to extinguishment systems.