Langdon Feltner

PhD candidate, School of Materials Engineering, Purdue University. Modeling and validation of industrial shot peening — linking stochastic impact processes to residual stress fields, surface fabric, and digital twins for manufacturing.

Who I am | Research | Dissertation | Contact

Who I am

I’m a PhD candidate in Materials Engineering at Purdue working in the Center for Surface Engineering and Enhancement (CSEE) and the Manufacturing and Materials Research Laboratories (MMRL). My dissertation pulls together numerical RVEs, Eshelby/inclusion-style analytical models, and experimental shot peening to explain why residual stress fields look heterogeneous even under nominally uniform process settings.

Current timeline: finishing ~Dec 2025; preparing several manuscripts (spectral fabric of residual stresses, flowsheet-based digital twin for shot peening, Eshelby-based formulations).

What I’m working on

Core threads I’m actively developing:

  • Eshelby-based residual stress modeling for shot peening — treating individual impacts as inclusion-like events, then superposing and PSD-correcting to match FEM ensembles.
  • RVE/FEM validation — 3D RVEs with random impact fields (10–500 impacts, 45–105 m/s) to benchmark the analytical/spectral model and quantify variability.
  • Flowsheet / digital-twin architecture — connecting media condition, impact energy, coverage (Poisson-type models), and stress outcomes so an industrial peening cell can be steered in real time.
  • ML surrogates for impact sequences — CNN + BiLSTM/attention models to learn stress-field evolution from multiple impacts, trained with Wasserstein-style losses.
  • Experimental tie-in — future strip/materials campaign (e.g. AM 316L vs SAE 1070) to map microstructural deformation mechanisms to the “fabric” we predict numerically.

Themes: stochasticity in surface enhancement, spectral descriptions, and making models usable by industry partners (not just in a notebook).

shot peening residual stress Eshelby / inclusions RVE FEM digital twin Wasserstein fitting

Who I work with

Academic / Purdue:

  • Advisor: Prof. Paul Mort
  • Center for Surface Engineering and Enhancement (CSEE)
  • MMRL Shot Peening Center of Excellence

Industry / collaborators:

  • Electronics Inc.
  • Progressive Surface
  • American Axle & Manufacturing
  • Sandia National Laboratories

Dissertation

Spectral Characterization and Reduced-Order Modeling of Industrial Shot Peening (PDF)

Dissertation covering Poisson impact modeling, spectral fabric, DIA-based media characterization, and ML-enabled flowsheets.

Contact / links

E-mail: lfeltner@purdue.edu
GitHub Pages: https://feltner515.github.io/homepage/