Prof. Panagiota Angeli

ThAMeS Multiphase, Department of Chemical Engineering, University College London, UK

E-mail: p.angeli@ucl.ac.uk

Bio

Prof Panagiota Angeli, FREng, FIChemE, is a Professor in the Department of Chemical Engineering at UCL, Deputy Head ED&I, and leads the ThAMeS Multiphase group. She obtained a Diploma in Chemical Engineering from the National Technical University of Athens and a PhD on Multiphase Flows at Imperial College London. She specializes on complex multiphase flows particularly those involving two liquid phases and their application in microchemical systems. Her research aims to link small scale interactions and interfacial phenomena to the macroscopic behaviour of the complex flows and to the development of predictive models. She has been investigating the effects of surfactants, particles and non-Newtonian rheologies on two-phase microchannel flows, as well as their applications to the analysis and intensification of metal separations, and to the manufacturing of complex formulations. The experimental investigations have been enabled by original and advanced sensing and measurement techniques, such as micro- and high speed Particle Image Velocimetry (PIV) and ultrasound. Prof Angeli’s work has been supported by substantial UK Research Council and European Union funding and by industry. She has been awarded a RAEng/Leverhulme Trust Fellowship and has participated and chaired UK EPSRC and international (Norway, Sweden, Ireland, Belgium) research funding review panels. She has published over 260 journal papers.
https://profiles.ucl.ac.uk/1932-panagiota-angeli 

Title

Microfluidics for complex droplet formulations

Abstract

Dispersions/emulsions of two immiscible liquids find numerous applications in pharmaceutical and healthcare formulations, food and agrochemicals. In recent years, microchannels have been extensively used to produce dispersions with small drop sizes and narrow size distributions. Surfactants and colloidal particles are commonly added to vary the interfacial properties, control the drop size, stabilise the emulsions and influence the final product rheology. Furthermore, the small volumes of microfluidic channels allow the application of external forces to control droplet formation.
In the talk, I will discuss the flow patterns and dynamic phenomena occurring during drop formation and break up in microfluidic channels in the presence of surfactants and colloidal particles. Detailed measurements of interface evolution and flow fields, based on fluorescent imaging and high speed particle image velocimetry, will be used to understand the physics of droplet formation and to develop predictive models. The application of external electrical fields to manipulate the drop formation patterns will be demonstrated. Recent results on the development of microfluidics for the formation of double dispersions will be shown.