Dr Benjamin Bugeat

I am a Lecturer in the School of Engineering, where I teach and carry out my research on Fluid Dynamics. I am primarily interested in the stability and transition to turbulence of shear flows. I use numerical and theoretical approaches, such as modal and non-modal stability analysis, resolvent analysis, and direct numerical simulation.

I obtained my PhD at Sorbonne University on the stability and optimal perturbations in compressible boundary-layer flows. Afterwards, I was a research associate at the University of Cambridge for two years, examining resolvent-based models for jet noise as part of the European project Daretomodel. I then joined TU Delft (Netherlands) as a research associate, where I investigated the stability of strongly stratified shear flows – a topic that still lies at the centre of my research today.

My research currently focuses on the stability and transition to turbulence of shear flows that feature strong variations of properties (viscosity, density, etc.). This is motivated by recent developments on the hydrodynamic behaviours of supercritical fluids in the transitional regime – a topic still largely unexplored. In the presence of heat transfer, these fluids can exhibit sharp variations of properties in the region of the phase diagram called the Widom line, which have been shown to significantly alter and enrich their dynamics in various shear flows. Using numerical and theoretical approaches, I examine simplified models that contain the key features of these flows, aiming to get new insights into the physical mechanisms at play.

Journal papers

P. C. Boldini, B. Bugeat, J. W. R. Peeters, M. Kloker and R. Pecnik (2024) Transient growth in diabatic boundary layers with fluids at supercritical pressure (submitted to Physical Review Fluids)

B. Bugeat, U. Karban, A. Agarwal, L. Lesshafft and P. Jordan (2024) Acoustic resolvent analysis of turbulent jets, Theoretical and Computational Fluid Dynamics (2024)

B. Bugeat, P. C. Boldini, A. M. Hasan and R. Pecnik (2024) Instability in strongly stratified plane Couette flow, with application to supercritical fluids, Journal of Fluid Mechanics, vol. 984, A31

M. Draskic, B. Bugeat and R. Pecnik (2024) The steady behaviour of the supercritical carbon dioxyde natural convection loop, Energy (2024): 130735

U. Karban, B. Bugeat, A. Towne, L. Lesshafft, A. Agarwal and P. Jordan (2023) An empirical model of noise sources in subsonic jets, Journal of Fluid Mechanics, vol. 965, A18

B. Bugeat, J.-C. Robinet, J.-C. Chassaing and P. Sagaut (2022) Low-frequency resolvent analysis of the laminar shock wave / boundary layer interaction, Journal of Fluid Mechanics, vol. 942, A43

U. Karban, B. Bugeat, E. Martini, A. Towne, A.V.G. Cavalieri, L. Lesshafft, A. Agarwal, P. Jordan and T. Colonius (2020) Ambiguity in mean-flow-based linear analysis, Journal of Fluid Mechanics, vol. 900, R5

B. Bugeat, J.-C. Chassaing, J.-C. Robinet and P. Sagaut (2019) 3D optimal forcing and response of the supersonic boundary layer, Journal of Computational Physics, vol 398, 108888

Conference papers

P.C. Boldini, R. Pecnik, J.W.R Peeters, B. Bugeat and P. Costa (2023) Direct numerical simulation of H-type transition in a flat-plate boundary layer with supercritical fluids, 14th internation ERCOFTAC Symposium on Engineering Turbulence Modelling and Measurements (ETMM14)

B. Bugeat, P.C. Boldini and R. Pecnik (2022) On the new unstable in the boundary layer flow of supercritical fluids, 12th International Symposium Turbulence and Shear Flow Phenomena (TSFP12)

U. Karban, B. Bugeat, A. Agarwal, L. Lesshafft and P. Jordan (2022) Modelling sources of noise in subsonic jets defined within resolvent framework, 28th AIAA/CEAS Aeroacoustics Conference