Christos N. Markides – Biographical Sketch

Advanced optical measurements for detailed insight into interfacial reacting flows

Clean Energy Processes (CEP) Laboratory, Department of Chemical Engineering, Imperial College London, U.K.

E-mail: c.markides@imperial.ac.uk

Bio

Christos Markides is Professor of Clean Energy Technologies, Head of the Clean Energy Processes Laboratory, and leads the Experimental Multiphase Flow Laboratory, which is the largest experimental space of its kind at Imperial College London. He is also, amongst other, Editor-in-Chief of journal Applied Thermal Engineering and founding Editor-in-Chief of new journal AI/Thermal-Fluids. He specialises in applied thermodynamics, fluid flow and heat/mass transfer processes in high-performance devices, technologies and systems for thermal-energy recovery, utilisation, conversion or storage. He has authored >400 journal and >350 conference articles on topics related to this talk. He has won multiple awards, including IMechE’s ‘Donald J. Groen’ outstanding paper prize in 2016, IChemE’s ‘Global Award for Best Research Project' in 2018, IChemE’s ‘Clean Energy Medal’ in 2025, and received Imperial College’s President Award for Research Excellence in 2017. He has an interest in technology transfer, innovation and commercialisation, most recently as a founding Director of Solar Flow. 

Abstract

Multiphase flows are commonly encountered in diverse applications, both in industrial and also natural environments. Of interest to us in this talk are two-phase, interfacial reacting flow systems where the production and accumulation of a solid phase can lead to severe operational challenges, and even complete flow blockage. To study such flows, we focus specifically on hydrate formation over sessile drops, where hydrates are inclusion compounds that form initially as thin solid films at the interface between two immiscible liquids, one of which is water.

Of importance in flows of interest are the thermodynamic conditions that create favourable drivers for hydrate formation at certain temperatures and pressures. However, beyond this, the hydrate formation process is accompanied by heat release due to its exothermic nature, and in cases where the flow transport processes have timescales of the order of the chemical kinetics, these processes can become coupled, leading to rich and complex phenomena.

In this talk, we will discuss recent efforts to develop and apply a range of advanced experimental techniques based on optical measurement principles in order to obtain high spatiotemporal resolution information on important scalar and vector fields in a target interfacial, reacting flow. We will discuss the challenges faced when attempting to perform such measurements, and proceed to present first-of-a-kind data on hydrates forming on the interfaces of sessile drops. We will close with an outlook on remaining opportunities and open questions that motivate further research in this field.