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CuDAFLOW: CUDA Discrete-Adjoint CFD

An FP32 GPU finite-volume RANS/LES solver built around an exact discrete adjoint whose residual derivatives are generated by CuAD — a source-to-source automatic-differentiation compiler for CUDA. Drives gradient-based shape optimization, Cf/Cp inverse design, and Spalart–Allmaras field inversion (FIML) from Python, with the adjoint linear solve in double precision through PETSc. Validated on Schubauer–Klebanoff transitional flat plate, Mach-7 axisymmetric shock/boundary-layer interaction, and the ONERA M6 transonic wing.

CuAD: Source-to-Source Automatic Differentiation for CUDA

An open-source, Tapenade-style source-to-source AD compiler for CUDA built on Clang LibTooling. It generates exact forward (tangent) and reverse (adjoint) GPU kernels from the original CUDA source, and powers the discrete adjoint of CuDAFLOW.

publications

Downwash/Outwash Analysis of eVTOL Configurations Using the Lattice-Boltzmann Method

Published in Asia Pacific International Symposium On Aerospace Technology (APISAT 2025), 2025

Analysis of aerodynamic characteristics of eVTOL configurations using the Lattice Boltzmann Method (LBM).

Recommended citation: Juneyoung Lim, Seunghyun Joo, and Kwanjung Yee. (2025). “Downwash/Outwash Analysis of eVTOL Configurations Using the Lattice-Boltzmann Method.” APISAT 2025.

Development and Validation of a Low-Fidelity Analysis Tool for Conceptual Design Accounting for Anti-Icing Energy Requirement (In Korean)

Published in KSAS Fall Conference 2025, 2025

Development and Validation of a Low-Fidelity Analysis Tool for Conceptual Design Accounting for Anti-Icing Energy Requirement

Recommended citation: Heesang Shin, Younghyo Kim, Seunghyun Joo, Kwanjung Yee. (2026). “Development and Validation of a Low-Fidelity Analysis Tool for Conceptual Design Accounting for Anti-Icing Energy Requirement.” KSAS Fall Conference 2025, (TBD).

AMADEVS: A Generalized Aircraft Modeling & Analysis Environment for Multidisciplinary Design

Published in AIAA SCITECH 2026 Forum, 2026

A generalized aircraft modeling and analysis environment with role-based components and a dual geometry–energy topology, demonstrated on Mars helicopter sizing, wing design under propeller–wing interaction, and UAM quadcopter handling qualities.

Recommended citation: Jeonghwan Kim, Seongjoong Park, Berenice Chatelain, Seonghyun Jeong, Jaehyun Ryu, Seunghyun Joo, and Kwanjung Yee. (2026). “AMADEVS: A Generalized Aircraft Modeling & Analysis Environment for Multidisciplinary Design.” AIAA SCITECH 2026 Forum, 1687.
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Data-Driven Algebraic Turbulence Transition Modeling via Hierarchical Separation of Physical Transition Mechanisms (In Korean)

Published in KSAS Spring Conference 2026, 2026

Data-Driven Algebraic Turbulence Transition Modeling via Hierarchical Separation of Physical Transition Mechanisms

Recommended citation: Seunghyun Joo, Younghyo Kim, Kwanjung Yee. (2026). “Data-Driven Algebraic Turbulence Transition Modeling via Hierarchical Separation of Physical Transition Mechanisms.” KSAS Spring Conference 2026, (TBD).

Mechanism-Separated Closed-Form Transition Modeling via Field Inversion and Symbolic Regression

Under Review, AIAA Journal, 2026

A closed-form, mechanism-separated laminar-to-turbulent transition model for the Spalart–Allmaras equation, built with field inversion and symbolic regression. Preprint: arXiv:2609.24162.

Recommended citation: Seunghyun Joo, Younghyo Kim, Kwanjung Yee. (2026). “Mechanism-Separated Closed-Form Transition Modeling via Field Inversion and Symbolic Regression.” Under review, AIAA Journal. arXiv:2609.24162.
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Vortex-Aware Reconstruction Selection for Reducing Vortex Dissipation, Informed by Field Inversion and Symbolic Regression

Under Review, Journal of Computational Physics (JCP), 2026

A vortex-aware (VA) reconstruction selector that reduces the numerical dissipation of under-resolved vortices in compressible flows while keeping the shock-capturing behavior of the baseline scheme.

Recommended citation: Seunghyun Joo, Yoonpyo Hong, Younghyo Kim, Kwanjung Yee. (2026). “Vortex-Aware Reconstruction Selection for Reducing Vortex Dissipation, Informed by Field Inversion and Symbolic Regression.” Under review, Journal of Computational Physics.

A Fully Coupled CFD–Free-Wake Discrete Adjoint for Rotor Design: Retaining Far-Wake Sensitivity

Work in Progress, 2026

The CFD residual and the periodic free-wake equilibrium residual are solved as one coupled system in both the primal and the adjoint, so the far wake is modeled cheaply but its design sensitivity is retained.

Recommended citation: Seunghyun Joo, Kwanjung Yee. “A Fully Coupled CFD–Free-Wake Discrete Adjoint for Rotor Design: Retaining Far-Wake Sensitivity.” Work in progress.

CuAD: Source-to-Source Automatic Differentiation of CUDA Kernels for Discrete Adjoints in Computational Fluid Dynamics

Preprint, arXiv (physics.flu-dyn), 2026

A source-to-source AD tool that writes tangent and adjoint CUDA kernels whose reverse sweep recomputes instead of storing, compared under one compiler with Clad and Enzyme and applied to a complete transonic Euler adjoint. Preprint: arXiv:2610.26694.

Recommended citation: Seunghyun Joo. (2026). “CuAD: Source-to-Source Automatic Differentiation of CUDA Kernels for Discrete Adjoints in Computational Fluid Dynamics.” arXiv preprint arXiv:2610.26694.
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talks

teaching

Teaching experience 1

Undergraduate course, University 1, Department, 2014

This is a description of a teaching experience. You can use markdown like any other post.

Teaching experience 2

Workshop, University 1, Department, 2015

This is a description of a teaching experience. You can use markdown like any other post.