BEGIN:VCALENDAR VERSION:2.0 PRODID:-//wp-events-plugin.com//7.4.0.1//EN TZID:Asia/Kolkata X-WR-TIMEZONE:Asia/Kolkata BEGIN:VEVENT UID:221@cds.iisc.ac.in DTSTART;TZID=Asia/Kolkata:20260821T140000 DTEND;TZID=Asia/Kolkata:20260821T150000 DTSTAMP:20260814T134013Z URL:https://cds.iisc.ac.in/events/m-tech-research-thesis-defense-cds-async hronous-computing-and-low-precision-approaches-towards-accelerating-flow-s imulations/ SUMMARY:M.Tech Research Thesis Defense: CDS: "Asynchronous computing and lo w-precision approaches towards accelerating flow simulations" DESCRIPTION:DEPARTMENT OF COMPUTATIONAL AND DATA SCIENCES\nM.Tech Research Thesis Defense\n\n\n\nSpeaker : Mr. Aswin Kumar A\nS.R. Number : 06-18-01- 10-22-24-1-24417\nTitle : "Asynchronous computing and low-precision approa ches towards accelerating flow simulations."\nThesis examiner : Prof. Ratn esh K. Shukla\, Mechanical Engineering\, IISc\nResearch Supervisor: Dr. Ko nduri Aditya\nDate &\; Time : August 21\, 2026\, 02:00 PM\nVenue : # 10 2 CDS Seminar Hall\n\n\n\nABSTRACT\n\nThe increasing computational cost of high-fidelity flow simulations at extreme scales has made communication o verheads arising from data movement and synchronization a major bottleneck in modern high-performance computing. At the same time\, emerging GPU- an d TPU-based architectures provide significantly higher throughput for low- precision arithmetic compared to traditional double-precision computations . This thesis investigates asynchronous computing approaches and low-preci sion numerical frameworks towards accelerating compressible and reacting f low simulations on future exascale supercomputers.\n\nThe primary focus of this work is the development and evaluation of asynchronous numerical met hods that relax communication and synchronization at a mathematical level while preserving the high-order accuracy of the underlying numerical schem es. Previously developed asynchrony-tolerant (AT) schemes are incorporated into the high-order compressible flow solver COMP-SQUARE in a multi-block framework for practically relevant flow problems in complex geometries. T wo asynchronous algorithms are considered: one that avoids communication o ver a few predetermined time steps\, and another that initiates communicat ion without enforcing synchronization. The numerical efficacy and scalabil ity of these asynchronous algorithms are demonstrated for several benchmar k problems\, including isentropic advection of a vortex\, the Taylor-Green vortex\, and the highly sensitive case of transitional flow over a NACA00 12 airfoil. Scaling experiments performed on up to 18\,432 cores demonstra te speed-ups of up to four times with respect to the baseline synchronous solver while maintaining solution accuracy. These results demonstrate the applicability of AT schemes to established CFD solvers for improving scala bility at extreme scales.\n\nThis work further extends the asynchronous co mputing framework to discontinuous Galerkin (DG) methods for compressible reacting flows. Although DG methods are attractive for their high arithmet ic intensity and their ability to accurately handle discontinuities such a s shocks and detonations\, their scalability is also limited by communicat ion bottlenecks arising from synchronization between processing elements ( PEs). An asynchronous discontinuous Galerkin (ADG) method is developed for chemically reacting flows with detailed chemistry\, and new asynchrony-to lerant weighted essentially non-oscillatory (AT-WENO) limiters are propose d to accurately capture discontinuities in the presence of communication d elays near PE boundaries. The numerical properties of the ADG framework ar e evaluated for spontaneous ignition\, premixed flame propagation\, and de tonation-wave propagation on a one-dimensional domain. The asynchronous so lver accurately captures ignition fronts and discontinuities while incurri ng negligible numerical errors at PE boundaries. Preliminary scaling studi es further demonstrate the potential of the ADG method as a basis for high ly scalable DG-based solvers for massively parallel combustion simulations .\n\nIn addition to asynchronous algorithms\, this thesis also explores lo w-precision approaches for reacting-flow simulations motivated by the hard ware characteristics of modern accelerators. A low-precision framework is investigated in which the chemical kinetics evaluations are performed in h alf precision (FP16)\, while the nonlinear temperature solve is performed in higher precision. The framework is assessed using lean hydrogen-air aut oignition with detailed chemical kinetics. Predictions of ignition delay a nd the evolution of temperature\, heat-release rate\, and species mass fra ctions show excellent agreement with FP64 reference solutions over a range of conditions. These preliminary findings demonstrate the feasibility of low-precision approaches for reacting-flow solvers while also identifying important considerations regarding robustness and generalizability.\n\nOve rall\, this thesis demonstrates that asynchronous computing methodologies and low-precision numerical approaches provide promising and complementary pathways towards improving the scalability and computational efficiency o f next-generation flow solvers for exascale scientific computing.\n\n\n\nA LL ARE WELCOME CATEGORIES:Events,Thesis Defense END:VEVENT BEGIN:VTIMEZONE TZID:Asia/Kolkata X-LIC-LOCATION:Asia/Kolkata BEGIN:STANDARD DTSTART:20250821T140000 TZOFFSETFROM:+0530 TZOFFSETTO:+0530 TZNAME:IST END:STANDARD END:VTIMEZONE END:VCALENDAR