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Salah Faroughi

Publications and source records attributed to Salah Faroughi.

2 recordsLinked to original sources

ViSIR: Vision Transformer Single Image Reconstruction Method for Earth System Models

Purpose: Earth system models (ESMs) integrate the interactions of the atmosphere, ocean, land, ice, and biosphere to estimate the state of regional and global climate under a wide variety of conditions. The ESMs are highly complex; thus, deep neural network architectures are used to model the complexity and store the down-sampled data. This paper proposes the Vision Transformer Sinusoidal Representation Networks (ViSIR) to improve the ESM data's single image SR (SR) reconstruction task. Methods: ViSIR combines the SR capability of Vision Transformers (ViT) with the high-frequency detail preservation of the Sinusoidal Representation Network (SIREN) to address the spectral bias observed in SR tasks. Results: The ViSIR outperforms SRCNN by 2.16 db, ViT by 6.29 dB, SIREN by 8.34 dB, and SR-Generative Adversarial (SRGANs) by 7.93 dB PSNR on average for three different measurements. Conclusion: The proposed ViSIR is evaluated and compared with state-of-the-art methods. The results show that the proposed algorithm is outperforming other methods in terms of Mean Square Error(MSE), Peak-Signal-to-Noise-Ratio(PSNR), and Structural Similarity Index Measure(SSIM).

cs.CV↗

Finite volume simulations of particle-laden viscoelastic fluid flows: application to hydraulic fracture processes

Accurately resolving the coupled momentum transfer between the liquid and solid phases of complex fluids is a fundamental problem in multiphase transport processes, such as hydraulic fracture operations. Specifically we need to characterize the dependence of the normalized average fluid-particle force $\langle F \rangle$ on the volume fraction of the dispersed solid phase and on the rheology of the complex fluid matrix. Here we use direct numerical simulations (DNS) to study the creeping flow ($Re\ll 1$) of viscoelastic fluids through static random arrays of monodisperse spherical particles using a finite volume Navier-Stokes/Cauchy momentum solver. The numerical study consists of $N=150$ different systems, in which the normalized average fluid-particle force $\langle F \rangle$ is obtained as a function of the volume fraction $ϕ$ $(0 < ϕ\leq 0.2)$ of the dispersed solid phase and the Weissenberg number $Wi$ $(0 \leq Wi \leq 4)$. From these predictions a closure law $\langle F \rangle(Wi,ϕ)$ for the drag force is derived for the quasi-linear Oldroyd-B viscoelastic fluid model which is, on average, within $5.7\%$ of the DNS results. Additionally, a flow solver able to couple Eulerian and Lagrangian phases is developed, which incorporates the viscoelastic nature of the continuum phase and the closed-form drag law. Two case studies were simulated using this solver, in order to assess the accuracy and robustness of the newly-developed approach for handling particle-laden viscoelastic flow configurations with $O(10^5-10^6)$ rigid spheres that are representative of hydraulic fracture operations.

physics.flu-dyn↗