Far-Field Exergy-Based Drag Decomposition of a Turbulent Blunt-Body Wake with Hybrid-LES
Justin DU PLESSIS, Drewan SANDERS, Tamas JÓZSA, Tom-Robin TESCHNER
Abstract This study investigates the application of the exergy balance to an unsteady turbulent wake using a Hybrid-LES methodology. A circular cylinder at Re = 5000 is simulated in ANSYS Fluent using IDDES, and the far-field exergy balance is evaluated across multiple control volumes to assess its accuracy and behaviour in a turbulent regime. The closest control volume shows reasonable agreement with the near-field drag with an error of 3.58%, but a progressive underestimation develops as the Trefftz plane is positioned further downstream. Analysis of the drag power components indicates that the reduction in mechanical exergy is not compensated by an equivalent increase in viscous dissipation, suggesting that part of the mechanical energy is being artificially dissipated or not fully captured within the IDDES framework. The findings highlight the sensitivity of exergy-based drag decomposition to numerical error in turbulent flows and provide a basis for future work aimed at identifying error sources and mitigating these errors.
Keywords
Exergy-Balance, Drag Decomposition, IDDES, Vortex Shedding
Published online 7/20/2026, 6 pages
Copyright © 2026 by the author(s)
Published under license by Materials Research Forum LLC., Millersville PA, USA
Citation: Justin DU PLESSIS, Drewan SANDERS, Tamas JÓZSA, Tom-Robin TESCHNER, Far-Field Exergy-Based Drag Decomposition of a Turbulent Blunt-Body Wake with Hybrid-LES, Materials Research Proceedings, Vol. 69, pp 254-259, 2026
DOI: https://doi.org/10.21741/9781644904251-45
The article was published as article 45 of the book CEAS – AIDAA Conference 2025
Content from this work may be used under the terms of the Creative Commons Attribution 3.0 license. Any further distribution of this work must maintain attribution to the author(s) and the title of the work, journal citation and DOI.
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