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Abstract We present a new computational fluid dynamics approach for simulating two‐phase flow in hybrid systems containing solid‐free regions and deformable porous matrices. Our approach is based on the derivation of a unique set of volume‐averaged partial differential equations that asymptotically approach the Navier‐Stokes Volume‐of‐Fluid equations in solid‐free regions and multiphase Biot Theory in porous regions. The resulting equations extend our recently developed Darcy‐Brinkman‐Biot framework to multiphase flow. Through careful consideration of interfacial dynamics (relative permeability and capillary effects) and extensive benchmarking, we show that the resulting model accurately captures the strong two‐way coupling that is often exhibited between multiple fluids and deformable porous media. Thus, it can be used to represent flow‐induced material deformation (swelling, compression) and failure (cracking, fracturing). The model's open‐source numerical implementation,hybridBiotInterFoam, effectively marks the extension of computational fluid mechanics into modeling multiscale multiphase flow in deformable porous systems. The versatility of the solver is illustrated through applications related to material failure in poroelastic coastal barriers and surface deformation due to fluid injection in poro‐visco‐plastic systems.
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Flow Supervision for Deformable NeRF
In this paper we present a new method for deformable NeRF that can directly use optical flow as supervision. We overcome the major challenge with respect to the computationally inefficiency of enforcing the flow constraints to the backward deformation field, used by deformable NeRFs. Specifically, we show that inverting the backward deformation function is actually not needed for computing scene flows between frames. This insight dramatically simplifies the problem, as one is no longer constrained to deformation functions that can be analytically inverted. Instead, thanks to the weak assumptions required by our derivation based on the inverse function theorem, our approach can be extended to a broad class of commonly used backward deformation field. We present results on monocular novel view synthesis with rapid object motion, and demonstrate significant improvements over baselines without flow supervision.
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- Award ID(s):
- 1925281
- PAR ID:
- 10482402
- Publisher / Repository:
- IEEE
- Date Published:
- ISBN:
- 979-8-3503-0129-8
- Page Range / eLocation ID:
- 21128 to 21137
- Format(s):
- Medium: X
- Location:
- Vancouver, BC, Canada
- Sponsoring Org:
- National Science Foundation
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