Nilotpal Chakraborty
PhD candidate, Mechanical Engineering, Virginia Tech · defending February 2027
I build the numerical machinery that closed solvers do not provide. Most of my work happens inside other people's codes: special functions written from scratch because the solver ships no maths library, a per-particle state channel packed into the bits of a float because the API carries no state, an HLLC Riemann solver added to an open-source SPH library after working out why its surface tension broke.
My application domain is particle ingestion in gas-turbine compressors — 100M+ cell campaigns on HPC, in the Pratt & Whitney–Rolls-Royce Academic Alliance. The portable part is the machinery, not the domain.
Three things worth reading
I found a numerical instability in an open-source SPH library
Its multiphase surface-tension model fails above Re ≈ 10³ — the fluid particles do not disorder, they leave the domain. I isolated it, reported it, and the maintainers' fix is now in a CMAME paper that acknowledges me. Read →
I gave a commercial solver a feature its API does not have
Damage history had to survive a Lagrangian track across MPI ranks, but the solver carries one float per particle. So the history went inside the float. Read →
I made simulations possible that the group could not run before
A scaling study that found the real bottleneck was memory, not cores — and changed what hardware we bought. Read →
Elsewhere
Acknowledged in Zhang, Lourenço & Hu, Computer Methods in Applied Mechanics and Engineering 444 (2025). Also acknowledged in Estes et al., Aerospace 12 (2025) 1038, for contributions to the Virginia Tech modelling effort. Second author on a multiphase perfusion model in Experimental and Computational Multiphase Flow (2023). Three first-author manuscripts from the dissertation in preparation.
Pratt Fellowship, Virginia Tech College of Engineering (2022) · Summer Cunningham Fellowship, VT Graduate School (2026) · Mitacs Globalink Research Fellowship (2019) · Shastri Research Fellowship (2019).