Subash Ranjan Kabat,
Bibhu Prasad Ganthia,
- Associate Professor and Principal, Electrical Engineering, Radhakrishna Institute of Technology and Engineering, Bhubaneswar, Odisha, India
- Assistant Professor, Electrical Engineering, Radhakrishna Institute of Technology and Engineering, Bhubaneswar, Odisha, India
Abstract
This study proposes a novel Physics-Adaptive Digital Twin with Neural-Operator Reduced-Order Modelling (PADT-NO) framework for predictive modelling of complex, nonlinear, and multiscale fluid flows. The proposed mathematical framework integrates fundamental conservation laws, Navier–Stokes dynamics, physics-constrained neural operators, adaptive reduced-order modelling, and uncertainty-aware state estimation within a unified computational architecture. Unlike conventional computational fluid dynamics and purely data-driven approaches, the proposed model dynamically couples high-fidelity physical information with a low-dimensional latent representation while preserving essential mass, momentum, and energy constraints. An adaptive mode-selection mechanism automatically modifies the reduced-order model complexity according to changes in flow regimes, enabling efficient representation of transient and strongly nonlinear flow structures. A physics-constrained learning objective simultaneously minimizes observational error, governing-equation residuals, boundary-condition violations, conservation errors, stability deviations, and uncertainty-calibration errors. The digital twin further incorporates parameter and model uncertainties to generate probabilistic flow predictions rather than deterministic estimates alone. The proposed framework is designed for rapid prediction, real-time monitoring, parameter estimation, and many-query fluid simulations while reducing computational dependence on expensive high-fidelity solvers. The resulting formulation provides a scalable mathematical pathway for next-generation intelligent fluid-mechanics modelling, particularly for turbulent, transient, and multiphysics flow systems. The system lowers the computing costs of high-fidelity solvers while supporting many-query fluid simulations, parameter estimation, real-time monitoring, and quick prediction. It offers a scalable approach to intelligent fluid-mechanics modelling with enhanced computational efficiency and predictive flexibility, especially for turbulent, transient, and multiphysics flow systems.
Keywords: Physics-informed modelling; digital twin; neural operators; reduced-order modelling; fluid dynamics
[This article belongs to Recent Trends in Fluid Mechanics ]
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Recent Trends in Fluid Mechanics
| Volume | 13 | |
| Issue | 02 | |
| Received | 12/09/2026 | |
| Accepted | 14/09/2026 | |
| Published | 15/09/2026 | |
| Publication Time | 3 Days |