Large Eddy Simulation of Turbulent Planar Offset Jet Aritra Roy Choudhury Research Engineer TCS Research June 7, 2023 Aritra Roy Choudhury PhD Applicant 1/22 Presentation Outline Academic Background Relevant Courses Professional Experience Research Experience Motivation Visible Research Output Aritra Roy Choudhury PhD Applicant 2/22 Academic Background Master of Science in Mechanical Engineering Indian Institute of Technology Madras, Chennai, India July 2019 - June 2022; CGPA: 8.8 M.S. Thesis: Large-Eddy Simulation of a Turbulent Planar Offset Wall Jet: The Effect of Ventilation Bachelor of Technology in Mechanical Engineering Seacom Skills University, Bolpur, India July 2014 - June 2018; 83.57% B.Tech Project: Analysis of Variation in Lift and Drag for a Two Dimensional Rotating Cylinder by Varying Flow Velocity and Rotation of Cylinder Aritra Roy Choudhury PhD Applicant 3/22 Academic Background AISSCE with Science Don Bosco School, Agartala, India March 2013; 86.4% AISSE Apeejay School, Kolkata, India March 2011; CGPA: 8.4 Aritra Roy Choudhury PhD Applicant 4/22 Relevant Courses Turbulence Modeling Introduction to Turbulence Incompressible Fluid Flow Computational Heat and Fluid Flow Numerical Methods in Thermal Engg Parallel Scientific Computing Aritra Roy Choudhury PhD Applicant 5/22 Professional Experience Research Engineer at TCS Research Responsible for incubation of novel simulation methodology and framework to be implemented on enterprise or physical digital twins. Created 3-dimensional aircraft trajectory simulation with rerouting using Bézier curve. Worked on mail service simulation using agent based discrete event simulation using in-house libraries. Aritra Roy Choudhury PhD Applicant 6/22 Research Experience Large-eddy simulation of a planar offset wall-jet with heat transfer: Characterization, turbulent kinetic energy and Reynolds shear stress budgets. ✹✑✇ ❚✟☞ ❇✟☎✠✔✝✄✕ ▲ ✏✞ ❲✝✆✆ ❉✂✖✂✔✂✠✡ ❙✞✄ ✝☛✆✂✠ ■✠✆ ✞ ✇ ✒✓✇ ❯☞☞ ✄ ❏ ✞ ❙☞✄ ✝✔ ❏ ✞ ❈ ✠✞ ✄ ▲✂✠ ❤ ②✶✴✷ ▲ ✏✞ ❲✝✆✆ ②✶✴✷✐✎ ❘ ✁✂✄✁☎✆✝✞✂✟✠ ❘ ✡✂✟✠ ■☛☞✂✠✡ ☛ ✠✞ ❘ ✡✂✟✠ Aritra Roy Choudhury ❲✝✆✆ ❏ ✞ ❘ ✡✂✟✠ PhD Applicant 7/22 ✉✶✴✷ ✉♠✌✍ Computational Setup The open-source computational fluid dynamics software OpenFOAM version 5.0 is used to perform all the simulations. An implicit pressure-based solver, pimpleFoam is used for performing the simulations. The simulation makes use of adaptive time-stepping algorithm that calculates and adjusts the time-step as the simulation proceeds based on CFL number. All the spatial derivatives are evaluated using second-order accurate central difference schemes. The temporal derivatives are evaluated using the second-order accurate Crank-Nicolson scheme. Adequacy of grid resolution is checked using the mesh quality parameter called LESIQν . Aritra Roy Choudhury PhD Applicant 8/22 Large-Eddy Simulation of a Planar Offset Wall-Jet (a) Outer jet layer (b) Inner jet layer (c) Near wall turbulent structures Aritra Roy Choudhury PhD Applicant 9/22 Heat Transfer and Flow Dynamics 40 Nu 30 20 10 Cf 0.004 0 -0.004 0.3 Cpw 0.2 0.1 0 -0.1 0 5 10 15 Aritra Roy Choudhury 20 x/w 25 PhD Applicant 30 35 10/22 40 Heat Transfer and Flow Dynamics Aritra Roy Choudhury PhD Applicant 11/22 Outer-Scaled TKE and Reynolds Shear Stress Budget in the Recirculation Region 0.08 Gain Gain 0.2 0.1 0 -0.04 0 0 0.5 Ctke Ptke εtke 1 y/y1/2 Loss Loss Ψtke Dt,tke Dν,tke -0.1 -0.2 0.04 1.5 (a) TKE budget Aritra Roy Choudhury 2 -0.08 Ψ⟨u´v´⟩ Dt,⟨u´v´⟩ Dν,⟨u´v´⟩ -0.12 -0.16 0 0.5 1 y/y1/2 C⟨u´v´⟩ P⟨u´v´⟩ ε⟨u´v´⟩ 1.5 (b) Reynolds shear stress budget PhD Applicant 12/22 2 Representation of TKE and Reynolds Shear Stress Budget at Different Regions Aritra Roy Choudhury PhD Applicant 13/22 Effect of Ventilation on Offset Jet Aritra Roy Choudhury PhD Applicant 14/22 Effect of Ventilation on Offset Jet ☎ ✆ ❱☞ ✌ ✍✎✏✍ ✚✛✜✣ ☎ ✉ ✴ ✧✚ ✧✧ ✧✢ ❱☞ ✌ ✍✎✏✒ ✠ ✟✥ ✄ ✉ ✁ ☎ ❱☞ ✌ ✍✎✏✑ ✚✛✜✢ ✦✤ ✵ ✁ ✄ ❱☞ ✌ ✍✎✍✍ ✚✛✜✤ ❊✓✔✕✖✗✘✙ ♠ ✥ ✂ ✥ ✁ ✥ ☎✥ ✆✥ ①✡☛ ✝✥ ✁✥ ✞✥ (a) Jet decay Aritra Roy Choudhury ❢ ❈ ✲ ✁ ☎ ✲ ✁ ✄ ✲ ✁ ✂ ✌ ✍ ✥ ✎✌ ✎✏ ✆ ✎✑ ☎ ①✟✠ ✎✒ ❱✡ ☛ ❱✡ ☛ ❱✡ ☛ ❱✡ ☛ ✝ (b) Coeffecient of friction PhD Applicant 15/22 ✁ ✁✥ ✁✥✝ ✁✥☞ ✞ Effect of Ventilation on the Near-wall Structures (a) VR = 0.00 (b) VR = 0.10 (c) VR = 0.14 (d) VR = 0.18 Aritra Roy Choudhury PhD Applicant 16/22 Effect of Ventilation in the Recirculation Region (a) VR = 0.00 (b) VR = 0.10 (c) VR = 0.14 (d) VR = 0.18 Aritra Roy Choudhury PhD Applicant 17/22 Effect of Ventilation on Vorticity Close to the Wall (a) VR = 0.00 (b) VR = 0.10 (c) VR = 0.14 (d) VR = 0.18 Aritra Roy Choudhury PhD Applicant 18/22 Conclusion Inner as well as outer scaled quantities attain self similar profiles for x/w ≥ 25. The peaks in Nu correlate with a change-of-sign of the Cf . Ptke and Ctke are balanced by Dt,tke and ϵtke . P⟨u′ v ′ ⟩ and C⟨u′ v ′ ⟩ are balanced by ψ⟨u′ v ′ ⟩ and Dt,⟨u′ v ′ ⟩ respectively. Ventilation suppresses turbulence and heat transfer while enhancing jet spread. Ventilation restricts formation of near-wall vortical structures, reducing heat transfer. Aritra Roy Choudhury PhD Applicant 19/22 Motivation The project aims to undertake a pioneering research topic and it will be a chance of a lifetime to be part of such a project and work with a multifaceted and talented team. Modeling and simulation of combustion needs to account for kinetics, heat transfer, thermo-chemistry, fluid dynamics, turbulence, FSI to name a few. The complex and coupled nature makes it challenging and an attractive problem to work on. I look forward to study phenomenons such as wrinkling and propagation of flame front, and generation and propagation of extinction holes in a high pressure, high strain condition subjected to liquid water injection. The research area is a rapidly evolving field with the potential to contribute to significant advancements in sustainable combustion, heat transfer and fluid dynamics. Aritra Roy Choudhury PhD Applicant 20/22 Visible Research Output Choudhury, A. & Anupindi, K. Large-eddy simulation of a planar offset wall-jet with heat transfer: Characterization, turbulent kinetic energy and Reynolds shear stress budgets. Int. J. Heat Mass Transf.. 191, 122847 (2022,8) Choudhury, A. & Anupindi, K. Large-eddy simulation of a planar offset-jet with heat transfer: The effects of ventilation. Int. J. Heat Mass Transf.. 208, 124061 (2023,7) Choudhury, A., P. Kakka & Anupindi, K. Evaluation of Turbulence Models for an Offset Planar Wall Jet with Heat Transfer. Proceedings of the 8th International and 47th National Conference on Fluid Mechanics and Fluid Power (FMFP). December 9-11, 2020, IIT Guwahati, Assam, India. (Conference Paper) Choudhury, A., P. Kakka & Anupindi, K. Large Eddy Simulation of an Offset Planar Wall Jet with Heat Transfer. NSM Workshop on High Performance Computing in Computational Fluid Dynamics 2020 (Presentation) Aritra Roy Choudhury PhD Applicant 21/22 Thank you. Aritra Roy Choudhury PhD Applicant 22/22
