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X-ORIGINAL-URL:https://aero.iisc.ac.in
X-WR-CALDESC:Events for Department of Aerospace Engineering
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TZID:Asia/Kolkata
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TZOFFSETFROM:+0530
TZOFFSETTO:+0530
TZNAME:IST
DTSTART:20260101T000000
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BEGIN:VEVENT
DTSTART;TZID=Asia/Kolkata:20260804T150000
DTEND;TZID=Asia/Kolkata:20260804T170000
DTSTAMP:20260919T024854
CREATED:20260803T045933Z
LAST-MODIFIED:20260804T105424Z
UID:10000143-1785855600-1785862800@aero.iisc.ac.in
SUMMARY:Multiphase Reactive Flows: From Dust Explosions to Metal-Fueled Detonations
DESCRIPTION:. \nExplosions in coal mines\, metal-processing facilities\, and other industrial settings occur with alarming regularity\, while reactive metal particles are being considered for energy-storage and propulsion applications. Despite a long history of research and its importance to safety and propulsion applications\, the physical mechanisms that govern the ignition\, combustion\, and detonation of reactive particles remain relatively unknown. Basic questions such as “How do particle size and thermal radiation affect dust-explosion propagation?”\, “What mechanisms govern the ignition and combustion of shock-dispersed metal powders?”\, and “How can reactive particles modify or sustain detonation waves?” remain unanswered. This presentation will discuss an ongoing numerical simulation effort aimed at answering these and other fundamental questions. This problem is addressed by solving a set of equations that couples a fully compressible reacting gas to a granular multiphase model that accounts for particle motion\, interphase drag and heat transfer\, and particle combustion. The results of these simulations indicate that shock propagation\, particle dispersal\, ignition\, combustion\, and thermal radiation are tightly coupled in a highly dynamic process. Results discussing the influence of particle diameter and thermal radiation on layered coal-dust explosions and the ignition and combustion of TNT-dispersed aluminum powder will be discussed. The presentation will close by discussing recent work exploring hybrid aluminum–hydrogen–air detonations\, including the role of particle size in extending detonation limits and modifying detonation structure. \n  \nSpeaker: Dr. Guhathakurta \nBiography:  \nDr. Guhathakurta received an M.Sc. degree in Physics from the Indian Institute of Technology Delhi\, and M.S. and Ph.D. degrees in Aerospace Engineering from the University of Florida. He subsequently held a postdoctoral appointment at Eindhoven University of Technology in the Netherlands. Dr. Guhathakurta is currently an Assistant Professor in the Department of Aerospace Engineering at Texas A&M University. His research focuses on a wide range of topics in multiphase reactive flows\, combustion\, and numerical simulation\, including dust explosions\, hybrid detonations\, thermal-radiation effects\, metal-particle combustion\, and high-speed propulsion.
URL:https://aero.iisc.ac.in/event/multiphase-reactive-flows-from-dust-explosions-to-metal-fueled-detonations/
LOCATION:Auditorium (AE 005)\, Department of Aerospace Engineering
CATEGORIES:AE Seminar
ATTACH;FMTTYPE=image/png:https://aero.iisc.ac.in/wp-content/uploads/2026/08/Dr-RD-Seminar-Aug-6.png
END:VEVENT
BEGIN:VEVENT
DTSTART;TZID=Asia/Kolkata:20260805T110000
DTEND;TZID=Asia/Kolkata:20260805T130000
DTSTAMP:20260919T024854
CREATED:20260728T061746Z
LAST-MODIFIED:20260802T102832Z
UID:10000141-1785927600-1785934800@aero.iisc.ac.in
SUMMARY:MTech(Res) : Design of an Ex-Situ Gas Sampling Layout with Various Probes and Their Performance Assessment for Accurate Emission Measurements
DESCRIPTION:Chemical kinetic mechanism development and validation require quantitative species data from canonical flames. Burner-stabilized pre -mixed flames provide a stationary post-flame region directly comparable to one-dimensional kinetic simulations. Ex-situ gas sampling delivers absolute CO and NO mole fractions from this region. The extraction step introduces two coupled biases. Reactions can continue inside the probe\, and the probe can perturb the flame upstream of the inlet. This thesis develops a coordinated ex-situ sampling framework for atmospheric McKenna burner-stabilized CH₄/air flames. The framework combines a sampling and dilution layout\, five sampling probes\, and a staged correction methodology. The measurements span fuel-lean to fuel-rich flames at three heights above the burner. The sampling and dilution layout is one of the principal contributions of the present work. The complete layout was designed and assembled in this work to adapt a portable gas analyzer (PG-350) for laboratory flame diagnostics. The PG-350 is built for stationary-source emissions monitoring rather than laboratory flame research. The design repurposes this industrial emissions instrument for high-precision species measurement in flames. The adapted instrument serves fundamental academic flame research. The layout delivers a conditioned\, metered\, and range-compatible sample to the analyzer. A vacuum pump extracts the sample using a sampling probe and drives it through the line. Two water-cooled drain separators\, designed and fabricated in this work\, remove the post-flame moisture. An Alicat mass flow meter measures the conditioned sample flow rate. A controlled N₂ dilution arrangement extends the CO measurement range beyond the analyzer’s full scale for the rich flames. Five sampling probes represent four reaction-quenching strategies. The aerodynamic-quench (AQ) probe was designed using a one-dimensional gas-dynamics model developed in this work. A brute-force screening selected its geometry against the pump and analyser constraints. The water-cooled (WC)\, pressure-quench (PQ)\, and uncooled probes were sized using non-reacting two-dimensional axisymmetric CFD. The uncooled-metal (UC-M) probe serves as a hot-wall reference. The uncooled-quartz (UC-Q) probe isolates the wall-material effect under the same geometry. Each probe was assessed experimentally and through two-dimensional probe-resolved reacting CFD in ANSYS Fluent. A residence-time method quantified the probe-induced upstream shift of the sampling location for the designed probes. A staged correction methodology recovers the sampled-gas composition from the conditioned analyzer reading. It corrects the mass flow meter reading for its gas-property mismatch. It then removes the imposed dilution and restores the moisture removed during conditioning. An independent route back-calculates the dilution ratio from paired CO₂ measurements. The methodology propagates the input uncertainties through the correction chain using the GUM framework. Reported values quote the expanded uncertainty on the corrected species. The corrected CO and NO were evaluated against a one-dimensional chemical kinetic simulation of the unperturbed flame. The comparison accounts for the probe-induced upstream shift of the sampling location. Each designed probe draws its sample from a location displaced toward the burner relative to its tip. The three designed probes were compared against the reference at their displaced sampling locations. The pressure-quench probe is the most consistent for both species. The water-cooled probe is a close alternative. The vacuum pump performance degraded due to moisture condensation in the pump head. Therefore\, it held the AQ suction above its design value throughout the campaign. The AQ probe is therefore off-design and cannot be ranked on equal terms. The uncooled-metal probe shows a large NO deficit in the rich flames from hot-wall surface reactions. The uncooled-quartz probe isolates the metal wall as the origin of this deficit. These rankings measure consistency with the kinetic reference rather than absolute accuracy. This work delivers outcomes of broader use to the combustion community. The framework offers documented guidelines to the community for ex-situ sampling experiments. It provides a comprehensive assessment of how each quenching strategy performs and which probe suits a given measurement. The corrected CO and NO data are suitable for chemical kinetic mechanism development and validation. Many detailed chemistry mechanisms exist\, yet reacting CFD of practical combustion devices requires reduced mechanisms that reproduce the target species profiles. The present setup allows reduced mechanisms to be validated quickly across flames spanning fuel-lean to fuel-rich conditions. A validated reduced mechanism can then support detailed CFD analysis of practical combustion systems. \n  \nSpeaker :  SARVAGYA SHARMA \nResearch Supervisor :  Irfan Ahmed Mulla
URL:https://aero.iisc.ac.in/event/mtechres-design-of-an-ex-situ-gas-sampling-layout-with-various-probes-and-their-performance-assessment-for-accurate-emission-measurements/
LOCATION:STC Conference Hall\, Ground Floor\, Department of Aerospace Engineering
CATEGORIES:Thesis Colloquium / Defence
ATTACH;FMTTYPE=image/jpeg:https://aero.iisc.ac.in/wp-content/uploads/2026/08/SARVAGYA.jpg
END:VEVENT
BEGIN:VEVENT
DTSTART;TZID=Asia/Kolkata:20260806T113000
DTEND;TZID=Asia/Kolkata:20260806T130000
DTSTAMP:20260919T024854
CREATED:20260717T092701Z
LAST-MODIFIED:20260802T105215Z
UID:10000137-1786015800-1786021200@aero.iisc.ac.in
SUMMARY:Ph .D.(Engg.): Explicit Filtering LES of turbulent swirling flows and multi-regime hydrogen flames
DESCRIPTION:The need to decarbonize power generation and aviation has established hydrogen as a promising fuel for next generation gas turbine combustion systems. However\, its high chemical reactivity significantly increases the propensity for autoignition and flashback under lean premixed conditions commonly used in hydrocarbon combustion systems. New combustor concepts based on direct fuel injection address these problems but typically produce lifted flames. These types of flames exhibit multi-regime combustion\, in which premixed and non-premixed combustion regions co-exist within highly turbulent swirling flow fields. Accurate numerical prediction of such reacting flows remains a major challenge as traditional models developed for hydrocarbon flames often fail to reliably predict the stabilization and combustion characteristics of multi-regime hydrogen flames. This thesis proposes a regime-sensitive combustion model using the thickened flame approach to extend the explicit filtering large eddy simulation (EFLES) method for computations of high Reynolds number (Re) reacting flows. A combustion regime index (CI) is defined based on the alignment between the gradients of mixture fraction and oxygen mass fraction to distinguish between premixed and non-premixed regions. The flame thickening treatment is applied selectively in premixed regions only. The model is implemented within an in-house high-order finite-difference flow solver that employs structured multi-block overlapping meshes to represent complicated geometries encountered in practical combustion systems. The predictive capability of the overall numerical methodology is systematically assessed through a series of increasingly complex flow configurations relevant to swirl-stabilized hydrogen combustors. The first case corresponds to an isothermal (Re ~ 27000) flow in the PRECCINSTA single nozzle swirl combustor. EFLES solutions show excellent agreement with the experimental data for flow field statistics and shape of the vortex breakdown bubble. Spectral proper orthogonal decomposition applied on time resolved velocity fields confirms that the EFLES method accurately reproduces the broadband turbulence structures and the coherent\, narrow band\, self-excited precessing vortex core oscillation. The combustion model performance is then evaluated using a canonical lifted slot jet flame configuration\, comprising a nitrogen diluted hydrogen slot jet of Re=8000 at 400 K issuing into a co-flow of heated air at 850 K. Entrainment of air into the jet core results in a stratified rich premixed flame alongside the primary non-premixed flame branch. The LES predicted flame lift-off height and flow field statistics are in good agreement with companion direct numerical simulation (DNS) results. Differences between LES and DNS solutions are small in premixed flame regions but increase with mesh spacing in non-premixed flame regions. The CI field is shown to clearly distinguish the two flame branches. This result is further validated a-posteriori using chemically explosive mode analysis (CEMA). Combined with EFLES\, the combustion model accurately predicts mixture fraction conditioned thermochemical statistics\, combustion mode distributions and the downstream evolution of premixed and diffusion flame branches in the lifted slot jet hydrogen flame. Finally\, a turbulent lifted hydrogen flame in the dual-swirl HYLON burner is investigated as a practical test case. The time-averaged mean flame shape and liftoff height is well captured in the LES solution. Good agreement is obtained between LES predictions and experimental measurements for statistics of velocity\, temperature\, and major-species mole fractions. CEMA reveals that a partially premixed flame branch is formed along the inner shear layer due to entrainment of hydrogen into the high-velocity annular air stream. The central diffusion flame branch is located within the vortex breakdown bubble between the fuel jet and the recirculating lean combustion products. The distribution of key thermochemical variables in mixture fraction space is also analyzed to characterize the two flame branches. Overall\, the results demonstrate that the proposed multi-regime thickened flame model\, coupled with explicit filtering LES provides a robust framework for high-fidelity LES of turbulent hydrogen flames. The methodology reproduces turbulent flow features\, flame stabilization and mixed combustion regimes across canonical and practical configurations. These results make the case for evaluating the performance of EFLES at higher operating pressures towards realizing a reliable computational engineering method for the design and analysis of future hydrogen gas turbine combustors. \nSpeaker :  ANINDYA DATTA \nResearch supervisor : Santosh Hemchandra
URL:https://aero.iisc.ac.in/event/ph-dengg-colloquium/
LOCATION:STC Seminar Hall\, Dept. of Aerospace Engineering
CATEGORIES:Thesis Colloquium / Defence
ATTACH;FMTTYPE=image/jpeg:https://aero.iisc.ac.in/wp-content/uploads/2026/08/ANINDYA.jpg
END:VEVENT
BEGIN:VEVENT
DTSTART;TZID=Asia/Kolkata:20260807T110000
DTEND;TZID=Asia/Kolkata:20260807T130000
DTSTAMP:20260919T024854
CREATED:20260804T053733Z
LAST-MODIFIED:20260811T060311Z
UID:10000144-1786100400-1786107600@aero.iisc.ac.in
SUMMARY:Ph.D. (Engg): Aerodynamics and Stability of a Generic Tailless UAV in Ground Effect
DESCRIPTION:Tailless UAVs are stealthy\, high-subsonic configurations used for deep penetration into contested airspace. These configurations have wing with moderate leading edge sweep angle with no definite fuselage and lack both horizontal tail and vertical tail which makes the aerodynamics of these configurations very unique. The increase in autonomous UAVs in recent times have led to renewed interest in this class of configurations. Autonomous take-off and landing of tailless UAVs are complex technologies that require a detailed understanding of the underlying aerodynamic flow physics. The current literature on the ground effects focusses mainly on conventional configuration or high swept delta wings.  This work focusses on understanding the aerodynamic behavior of a typical tailless UAV near the ground and its influence on the stability characteristics. RANS CFD analysis is carried out at different ground heights\, angle of attack and side slip angle. Studies are also carried to understand the effect of roll orientation effect on the ground effects. The  effect of ground on the elevon behavior near the ground are also brought out. Unsteady CFD Analysis are conducted for different sink rates and pitch angles and compared with Static Ground Effects.\n The lift coefficient under Steady Ground Effects was observed to decrease near the ground at lower angle of attack and increase at high angle of attack. The region between the ground and aircraft acts like a venturi at low angle of attack. At high angle of attack\, ramming effect is observed due to increase in the pressure on the bottom surface. The drag coefficient does not change at lower angle of attack whereas significant reduction is observed at higher angle of attack due to the reduction in the induced drag.  The UAV shows a reduction in directional stability near the ground. The rolling moment due to side slip angle shows a stable behavior near the ground.  The roll orientation of the UAVs impacts the rolling moment behavior near the ground providing increased rolling moment near the ground which has a tendency to counter the direction of the roll.  Unsteady CFD Analysis is conducted for different sink rates and pitch angles and compared with Static Ground Effects which shows significant change especially at lower pitch angles. \n The aerodynamic changes introduced by the  presence of ground impacts the Stability of the UAV significantly.  The Stability  changes are particularly important for the tailless UAV as it is neutrally stable in the longitudinal and directional plane. A increase in Static Margin of 0.5% is observed at the lowest ground  height  (h/b = 0.15). There is also marginal increase in weather cock stability (Cnβ)  and roll stability (Clβ) at high angle of attack near the ground. The dynamics of the tailless UAV near the ground has interesting behavior near the ground. The short period mode has stabilizing behavior near the ground whereas the Dutch roll tends to be slightly unstable near the ground. The roll orientation of the UAV seems to impact the Dutch roll mode changing from slightly unstable to a slightly stable behavior.  The aerodynamics and stability aspects are highly coupled for tailless UAV. The understanding of tailless UAV near the ground will be key for development of control schemes for robust take-off and landing of these Configurations. \n  \nSpeaker :  B Saravanan \nResearch Supervisor :  N Balakrishnan \n 
URL:https://aero.iisc.ac.in/event/aerodynamics-and-stability-of-a-generic-tailless-uav-in-ground-effect/
LOCATION:AE Conference Room \, AE 003
CATEGORIES:Thesis Colloquium / Defence
ATTACH;FMTTYPE=image/jpeg:https://aero.iisc.ac.in/wp-content/uploads/2026/08/Saravanan.jpg
END:VEVENT
BEGIN:VEVENT
DTSTART;TZID=Asia/Kolkata:20260810T110000
DTEND;TZID=Asia/Kolkata:20260810T130000
DTSTAMP:20260919T024854
CREATED:20260808T055603Z
LAST-MODIFIED:20260811T060138Z
UID:10000145-1786359600-1786366800@aero.iisc.ac.in
SUMMARY:Ph.D. (Engg):Tonal acoustic radiation from turbulent subsonic jets
DESCRIPTION:Acoustic tones in the near field of a Mach 0.9\, Reynolds number 10^6 round jet are investigated using large-eddy simulations (LES) performed with the explicit filtering LES (EFLES) approach. The jet is issued into the ambient through a cylindrical nozzle. Pressure spectra at observer locations in the upstream direction reveal the presence of tones which are 15–20 dB more intense than the background turbulent mixing noise. Spectral Proper Orthogonal Decomposition (SPOD) of the pressure field in the near-nozzle region reveals two distinct categories of tones. The first category comprises tones whose frequency corresponds to high order radial and azimuthal ductmodes of the nozzle. Their spatial amplitude distribution revealed by SPOD at these frequencies show significant support within the nozzle as expected for the natural hard-wall duct modes. These duct modes are scattered at the nozzle lip and radiate in the upstream direction and explain the tonal radiation observed in the LES at their corresponding frequencies. This mechanism has been extensively studied using Wiener-Hopf models applied to a cylindrical vortex sheet (Munt\, 1977; Rienstra\, 2003; Samanta and Freund\, 2008). The second category of tones observed have frequencies that are not hard wall duct mode frequencises. Their spatial amplitude distribution revelaed by SPOD for these frequencies is characterized by significant support within the jet potential core. Empirical dispersion relations constructed from the LES suggest that these tones arise from resonance in the potential core due to coupling between the upstream-propagating guided jet mode (GJM) and the upstream- and downstream-propagating duct-like modes (Schmidt et al.\, 2017; Towne et al.\, 2017) near the upper cut-off frequency of the guided jet mode (Bogey\, 2021). However\, the mechanism by which tones radiate from the potential core has not yet been established. This motivates the theoretical investigation in this thesis that focuses on the dynamics of the guided jet mode and its interaction with the nozzle lip leading to tonal upstream acoustic radiation. The interaction between the GJM and the nozzle lip is analyzed using a Wiener–Hopf formulation with the jet modelled as a semi-infinite cylindrical vortex sheet and the nozzle with a vanishingly-thin sharp edge. When the GJMs are cut-on\, these solutions show that an incident GJM is reflected as a downstream-traveling soft-duct mode\, a scattered Kelvin–Helmholtz (K–H) mode and a transmitted upstream-traveling hard-wall duct mode. The reflective efficiency of GJM increases with frequency and is greatest near their upper cut-off frequency. This explains why tones associated with potential core resonance occur near the upper cut-off frequency of the GJM. In addition\, the GJM is scattered as acoustic waves to the far field\, primarily in the upstream direction. The scattered wavefronts are most intense along the outer nozzle wall. The scattered waves propagate to the far field where they generate distinctive directivity patterns that show excellent agreement with the LES-computed far-field directivity reported by Bogey (2021). These results provide a mechanistic explanation for how tones generated by potential core resonance radiate to the far field through scattering of the guided jet mode at the nozzle lip. Acoustic tones in the near field of a Mach 0.9\, Reynolds number 10^6 round jet are investigated using large-eddy simulations (LES) performed with the explicit filtering LES (EFLES) approach. The jet is issued into the ambient through a cylindrical nozzle. Pressure spectra at observer locations in the upstream direction reveal the presence of tones which are 15–20 dB more intense than the background turbulent mixing noise. Spectral Proper Orthogonal Decomposition (SPOD) of the pressure field in the near-nozzle region reveals two distinct categories of tones. The first category comprises tones whose frequency corresponds to high order radial and azimuthal ductmodes of the nozzle. Their spatial amplitude distribution revealed by SPOD at these frequencies show significant support within the nozzle as expected for the natural hard-wall duct modes. These duct modes are scattered at the nozzle lip and radiate in the upstream direction and explain the tonal radiation observed in the LES at their corresponding frequencies. This mechanism has been extensively studied using Wiener-Hopf models applied to a cylindrical vortex sheet (Munt\, 1977; Rienstra\, 2003; Samanta and Freund\, 2008). The second category of tones observed have frequencies that are not hard wall duct mode frequencises. Their spatial amplitude distribution revealed by SPOD for these frequencies is characterized by significant support within the jet potential core. Empirical dispersion relations constructed from the LES suggest that these tones arise from resonance in the potential core due to coupling between the upstream-propagating guided jet mode (GJM) and the upstream- and downstream-propagating duct-like modes (Schmidt et al.\, 2017; Towne et al.\, 2017) near the upper cut-off frequency of the guided jet mode (Bogey\, 2021). However\, the mechanism by which tones radiate from the potential core has not yet been established. This motivates the theoretical investigation in this thesis that focuses on the dynamics of the guided jet mode and its interaction with the nozzle lip leading to tonal upstream acoustic radiation. The interaction between the GJM and the nozzle lip is analyzed using a Wiener–Hopf formulation with the jet modelled as a semi-infinite cylindrical vortex sheet and the nozzle with a vanishingly-thin sharp edge. When the GJMs are cut-on\, these solutions show that an incident GJM is reflected as a downstream-traveling soft-duct mode\, a scattered Kelvin–Helmholtz (K–H) mode and a transmitted upstream-traveling hard-wall duct mode. The reflective efficiency of GJM increases with frequency and is greatest near their upper cut-off frequency. This explains why tones associated with potential core resonance occur near the upper cut-off frequency of the GJM. In addition\, the GJM is scattered as acoustic waves to the far field\, primarily in the upstream direction. The scattered wavefronts are most intense along the outer nozzle wall. The scattered waves propagate to the far field where they generate distinctive directivity patterns that show excellent agreement with the LES-computed far-field directivity reported by Bogey (2021). These results provide a mechanistic explanation for how tones generated by potential core resonance radiate to the far field through scattering of the guided jet mode at the nozzle lip. Comparison of the Wiener–Hopf predictions with the LES-computed pressure spectra in the present investigation reveals excellent agreement at lower frequencies but deviations at higher frequencies. At lower frequencies\, the SPOD modes are qualitatively similar to the corresponding Wiener–Hopf solutions. In contrast\, at higher frequencies\, the scattered waves originating from the nozzle lip undergo secondary scattering at the slanted section of the outer nozzle wall\, causing them to lift away from the wall. The findings suggest two possible strategies for mitigating the tones generated by the potential core resonance: (i) modifying the nozzle-lip geometry and (ii) modifying the outer nozzle-wall geometry. \n  \nSpeaker: NAGA SARAS CHANDAN VEMPATI \nResearch Supervisor: Santosh Hemchandra
URL:https://aero.iisc.ac.in/event/ph-d-enggtonal-acoustic-radiation-from-turbulent-subsonic-jets/
LOCATION:STC Seminar Hall\, Dept. of Aerospace Engineering
CATEGORIES:Thesis Colloquium / Defence
ATTACH;FMTTYPE=image/jpeg:https://aero.iisc.ac.in/wp-content/uploads/2026/08/NAGA.jpg
END:VEVENT
BEGIN:VEVENT
DTSTART;TZID=Asia/Kolkata:20260814T110000
DTEND;TZID=Asia/Kolkata:20260814T133000
DTSTAMP:20260919T024854
CREATED:20260811T114531Z
LAST-MODIFIED:20260824T064859Z
UID:10000146-1786705200-1786714200@aero.iisc.ac.in
SUMMARY:MTech(res)  Parallel Particle Tracking for Turbulent Round Jets
DESCRIPTION:Particle tracking in turbulent jets is essential for an accurate Lagrangian understanding of jet flows. While parallel algorithms and numerical schemes to compute flow fields can be scaled to a large number of computing processes\, the same is not necessarily true for particle tracking. This thesis presents an analysis of the parallel efficiency of particle tracking in the specific context of round turbulent jets.\nA particle tracking module was developed and integrated with Xcompact3d – a well-established flow solver with strong and weak scaling up to 100\,000 processes. The module uses trilinear velocity interpolation scheme and a first-order Euler integration scheme with sub-stepping for particle advancement. Velocity data is exchanged via a halo API provided by 2DECOMP&FFT – the domain decomposition library that Xcompact3d builds upon. Particle data is exchanged via MPI collectives. Additional exchange algorithms that aim to avoid the scalability limitations of MPI collectives are available to the user. However\, the choice of algorithms for data exchange is often constrained by flow and simulation parameters. \nThe module is validated using an analytical velocity field and subsequently employed for DNS and LES of turbulent jets with particles. Particle concentration profiles are used to assess accuracy. The results demonstrate the capability of the integrated code to accurately track particles over multiple simulation runs. The particle numbers used for these simulations are comparable or higher than the number of grid points as opposed to most studies in the literature where particle numbers are much lower than the number of grid points. \nA detailed wall-time and particle-load analysis is done to assess the parallel efficiency and identify performance limitations. Particle tracking and exchange are the largest contributors to simulation time after flow field computation. The wall-time for particle tracking increases with the number of particles in the domain. A large difference is observed between the average wall-time and maximum wall-time across computing processes which is attributed to particle load imbalance. In contrast\, the particle exchange wall-time across computing processes is similar because of the MPI collectives being used for particle data exchange. However\, the number of particles\, and consequently\, the size of data being exchanged\, is a small fraction of the number of particles being tracked. A particle load-analysis reveals considerable variation in the number of particles being tracked by individual processes\, with the maximum difference in particle count amongst processes being as high as three orders of magnitude. \nThe results obtained highlight the challenges in implementing particle tracking at scale. While strategies to mitigate the impact of non-scalable collectives for particle exchange exist\, algorithms to mitigate the severe particle-load imbalance in the context of turbulent jets have not been adequately studied and are urgently required\, which is identified as the key area for future work. \n  \nSpeaker : Nikhil Jayswal \nResearch Supervisor: Prof. Joseph Mathew
URL:https://aero.iisc.ac.in/event/mtechres-parallel-particle-tracking-for-turbulent-round-jets/
LOCATION:STC Seminar Hall\, Dept. of Aerospace Engineering
CATEGORIES:Thesis Colloquium / Defence
ATTACH;FMTTYPE=image/jpeg:https://aero.iisc.ac.in/wp-content/uploads/2026/08/Nikhil-Jayswal.jpg
END:VEVENT
END:VCALENDAR