Prof.Andrea Cioncolini

Guangdong Technion-Israel Institute of Technology, China.

Bio

Prof. Andrea Cioncolini completed his studies at the Polytechnic University of Milan (Italy) with a Laurea degree (equivalent to BEng plus MEng) and a PhD in Nuclear Engineering, with specialty in nuclear thermal-hydraulics. Successively, he completed a MSc in Mathematics at the University of Pavia (Italy), with specialty in computational fluid dynamics.

After graduating, he started his career as Senior Engineer/Scientist for the nuclear vendor Westinghouse Electric Company in Pittsburgh (USA), where he worked on transient/safety analysis of water-cooled nuclear power plants and on the thermal-hydraulic design/testing of small-modular water-cooled nuclear reactor systems. Successively, he moved to the Chalmers University of Technology in Gothenburg (Sweden) and then to the EPFL-The Swiss Federal Institute of Technology in Lausanne (Switzerland), where he spent six years working as Post-Doctoral Researcher on macro-micro-scale two-phase flow modelling for demanding cooling applications (nuclear fission/fusion reactors, microelectronics systems, and high-energy physics particle detectors). He joined the University of Manchester (UK) in 2013 as Lecturer in Thermal-Hydraulics, and was successively promoted to Senior Lecturer in 2018 and then to Reader in 2021. He joined the Guangdong Technion-Israel Institute of Technology in Shantou (China) in 2022 as Associate Professor.

His research interests include experimental and computational thermo-fluid dynamics, convective flow boiling and multiphase flows, flow-induced vibrations, and flexible fluid-structure interactions.

He has been associated with over USD18M research funding (USD570k as personal credit) and has been PI in two research grants funded by EPSRC-Engineering and Physical Science Research Council (UK). He has authored/coauthored 1 book, 2 book chapters, and over 100 refereed papers in journals and conferences. He is Associate Editor of the Journal of Mechanical Engineering Science (Proc. IMechE) since 2020.

He has taught Heat Transfer, Fluid Mechanics, Advanced Engineering Fluid Mechanics, Numerical Methods in Heat Transfer, Introduction to Scientific and Engineering Calculations, and Probability and Statistics in Mechanical Engineering. He is Fellow of the Higher Education Academy (UK) since 2018, and he has supervised 6 PhDs to completion and over 20 MSc Theses.

Title

Liquid Entrainment in Annular Gas-Liquid Two-Phase Flows: A Critical Assessment of Experimental Data and Prediction Methods

Abstract

Among the various flow patterns that can be observed when a two-phase gas–liquid mixture flows in a tube or channel, the annular flow pattern is by far the most frequently encountered. Representative examples of two-phase flow systems where annular flows are commonplace include evaporators and steam generators, microelectronics and power electronics heat sinks, boiling water nuclear reactors, refrigeration and air conditioning units, chemical processing fluid systems, and oil and gas transportation pipelines.

Annular flows are characterized by a continuous liquid film flowing along the channel wall and surrounding a gas core laden with entrained liquid droplets, so that part of the liquid phase flows as a continuous film that steams along the channel wall, whilst the rest of the liquid phase flows as a spray of droplets entrained within the gas core. Despite their apparent morphological simplicity, annular flows are characterized by a rich and intricated physics that combines wall-bounded and free-surface flow conditions with interface deformation and liquid atomization.

A key flow parameter in the analysis and modeling of annular flows is the Entrained Liquid Fraction (ELF), which is defined as the ratio of the mass flow rate of the entrained liquid droplets to the total liquid mass flow rate. The ELF is dimensionless and bounded between zero and one: ELF values close to zero characterize annular flows where most of the liquid flows in the film, whilst ELF values close to one are typical of annular flows close to the transition to mist flow, where most of the liquid is in the form of entrained droplets.