Abstract

Flame-wall interaction (FWI) in combustion systems affects thermal efficiency, emissions, and fire safety. Wall cooling, essential for structural integrity, causes heat loss, leading to flame quenching, unburned reactant emissons, and potential flashback in low-velocity wall regions. The demand for compact and micro-combustors highlights the importance of understanding FWI for efficient and environmentally friendly designs. FWI involves complex turbulent interactions near walls, where temperature gradients result in significant heat flux and spatially varying combustion dynamics. Recent advances in high-performance computing enable Direct Numerical Simulations (DNS) that provide detailed insights into premixed FWI within turbulent boundary layers without relying on physical approximations. This seminar will demonstrate how FWI affects global features (e.g., flame location, wall heat flux, shear stress), turbulence (e.g., enstrophy, Reynolds stress anisotropy), and scalar statistics, with variations influenced by fuel Lewis number and thermal wall conditions. The implications for turbulence modeling will be discussed, with a focus on linking wall heat flux, shear stress, and turbulent burning velocity for better predictive modelling of premixed FWI in turbulent boundary layers.

Biography

Prof. Nilanjan Chakraborty is a Professor of Fluid Dynamics at Newcastle University's School of Engineering since 2011, where he currently serves as the Deputy Director of Research. He led the Fluid Dynamics and Thermal Systems research group at Newcastle University from 2011 to 2023. He obtained his bachelor’s and master’s degrees in mechanical engineering from Jadavpur University, Kolkata, India, and the Indian Institute of Science, Bangalore, respectively. After gaining industrial experience at General Electric (GE) India, he was awarded the prestigious Gates Cambridge Scholarship to pursue a PhD at Cambridge University. His research spans areas such as Direct Numerical Simulation (DNS) and Large Eddy Simulation (LES) of turbulent combustion, natural convection of non-Newtonian fluids, heat transfer in manufacturing processes like casting and welding, and laser-aided manufacturing applications, including laser surface alloying. Prof. Chakraborty has received numerous accolades, including the Gaydon Prize (2004), Hinshelwood Prize (2006), a Distinguished Paper Award at the 32^nd International Combustion Symposium, and the Hind Rattan Award (2015), one of India’s highest honors for Non-Resident Indians. In 2021, he was elected as a Fellow of the Combustion Institute. With over 350 peer-reviewed journal papers and 200 conference publications, he continues to make a significant impact in the fields of engineering and combustion research.