Senior DevTech Engineer · NVIDIA

Clement
Etienam
Ph.D.

GPU-accelerated reservoir simulation, physics-informed neural operators, and Bayesian inverse problems. Building the next generation of scientific machine learning for subsurface flow and carbon capture.

Physics Informed neural Operator HPC Reservoir Simulation CCUS Inverse Problems CUDA Machine Learning Gaussian process Sparse Linear Algebra
Clement Etienam
159
Citations
01 —

About


I am a Senior DevTech Engineer in the Energy team at NVIDIA, working at the intersection of GPU computing, scientific machine learning, and subsurface physics. My research focuses on making physics-informed neural operators fast and accurate enough to replace traditional numerical simulators in real-world energy workflows — from reservoir management to carbon capture and storage at scale.

My PhD at the University of Manchester (supervised by Oliver Dorn and Rossmary Villegas, with a postdoc under Kody Law) established a deep foundation in Bayesian inverse problems, ensemble Kalman methods, and surrogate modelling. The central challenge: given noisy observations y, recover the unknown parameter field u by characterising the posterior

π(u | y) ∝ exp(−½‖G(u) − y‖²Γ) · π₀(u)

where G : uy is the forward operator — classically a full black-oil PDE solve, now replaced by a learned neural surrogate. This work is applied directly to reservoir history matching, CO₂ plume migration, and ensemble-based inversion (ES-MDA, aREKI) with generative priors.

I developed the CCR (Cluster Classify Regress) framework for learning highly nonlinear discontinuous functions across sharp phase boundaries — a persistent failure mode for standard regression. Building on this, I have applied PINO and FNO-based surrogates to the Norne field black-oil benchmark (46×112×22 grid, multi-phase, multi-well), solving the parametric PDE family

t(φ Sα) + ∇·Fα(S, p, K) = qα

across thousands of permeability realisations in a single forward pass, achieving up to 6000× speedup over conventional simulators. I contribute to the NVIDIA PhysicsNeMo open-source framework.

6000×
Simulation speedup
159
Total citations
10+
Publications
10yr
Research career
02 —

Research


2026
Sequential Physics-Constrained Neural Operator Forward Modeling for the Norne Reservoir System
C. Etienam, Y. Juntao, O. Ovcharenko, N. Luiken, T. Onishi, N. Moridis, I. Said
arXiv:2605.28909
2024
Reservoir History Matching of the Norne Field with Generative Exotic Priors and a Coupled Mixture of Experts — PINO Forward Model
C. Etienam, Y. Juntao, O. Ovcharenko, I. Said
arXiv:2406.00889
2025
Accelerating Porous Media Flow Simulations with Fourier Neural Operators: An Application to Geologic Storage of CO₂
A. Chandra, M. Koch, S. Pawar, A. Panda, K. Azizzadenesheli, J. Snippe, F. O. Alpak, F. Hariri, C. Etienam, P. Devarakota, A. Anandkumar, D. Hohl
★ Advanced Theory and Simulations, Wiley · 2025
2024
A Novel AI-Enhanced Reservoir Characterization with a Combined Mixture of Experts — NVIDIA Modulus-based PINO Forward Model
C. Etienam, Y. Juntao, I. Said, O. Ovcharenko, K. Tangsali, P. Dimitrov, K. Hester
arXiv:2404.14447
2022
LIPS — Learning Industrial Physical Simulation Benchmark Suite
M. Leyli-Abadi, A. Marot, J. Picault, D. Danan, M. Yagoubi, B. Donnot, S. Attoui, P. Dimitrov, A. Farjallah, C. Etienam
★ NeurIPS 2022
2020
Ultra-fast Deep Mixtures of Gaussian Process Experts
C. Etienam, K. J. H. Law, S. Wade
arXiv:2006.13309
2019
CCR: Cluster Classify Regress — A General Method for Learning Discontinuous Functions
D. E. Bernholdt, M. R. Cianciosa, C. Etienam, D. L. Green, K. J. H. Law, J. M. Park
★ AIMS Foundations of Data Science · 2019
2019
4D Seismic History Matching Incorporating Unsupervised Learning
C. Etienam
arXiv:1905.07469
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Code


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