arXiv subjects

Giuseppe Antonio Zampogna

Publications and source records attributed to Giuseppe Antonio Zampogna.

4 recordsLinked to original sources

arXiv2026

Nested homogenization of xylem-inspired porous fluidic networks

Fluidic networks may contain hierarchical porous structures in which transport across macroscopic interfaces is controlled by geometrical features at multiple nested length scales. Direct resolution of all these scales rapidly becomes computationally prohibitive for network-scale studies, while reduced descriptions require a priori effective hydraulic properties. Here, we develop a nested homogenization framework for rigid porous interfaces under single-phase viscous flow. The pore-scale structure is first replaced by an effective stress-jump interface law, which is then embedded as an internal interface condition within a second characteristic problem at the intermediate scale. This successive upscaling propagates the pore-scale geometry through effective tensors to obtain a closure for flow across the whole porous structure. The approach is validated against fully resolved simulations at the mesoscopic and macroscopic scales, for two xylem-inspired channel configurations, and accurately captures pressure drops and flow redistribution while strongly reducing computational cost. The framework provides a tractable bottom-up description of a network composed of nested porous membranes and a basis for extensions to deformable structures and multiphase flows.

physics.flu-dyn↗

arXiv2025

Effective flows across diffusio-phoretic membranes

Flows enabled by phoretic mechanisms are of significant interest in several biological and biomedical processes, such as bacterial motion and targeted drug delivery. Here, we develop a homogenization-based macroscopic boundary condition which describes the effective flow across a diffusiophoretic microstructured membrane, where the interaction between the membrane walls and the solute particles is modeled via a potential-approach. We consider two cases where potential variations occur (i) at the pore scale and (ii) only in the close vicinity of the boundary, enabling a simplified version of the macroscopic flow description, in the latter case. Chemical interactions at the microscale are rigorously upscaled to macroscopic phoretic solvent velocity and solute flux contributions, and added to the classical permeability and diffusivity properties of the membrane. These properties stem from the solution of Stokes-advection-diffusion problems at the microscale, some of them forced by an interaction potential term. Eventually, we show an application of the macroscopic model to develop minimal phoretic pumps, showcasing its suitability for efficient design and optimization procedures.

physics.flu-dyn↗

arXiv2024

Quasi-Linear Homogenization for Large-Inertia Laminar Transport across Permeable Membranes

Porous membranes are thin solid structures that allow the flow to pass through their tiny openings, called pores. Flow inertia may play a significant role in several filtration flows of natural and engineering interest. Here, we develop a predictive macroscopic model to describe solvent and solute flows past thin membranes for non-negligible inertia. We leverage homogenization theory to link the solvent velocity and solute concentration to the jumps of solvent stress and solute flux across the membrane. Within this framework, the membrane acts as a boundary separating two distinct fluid regions. These jump conditions rely on several coefficients, stemming from closure problems at the microscopic pore scale. Two approximations for the advective terms of Navier-Stokes and advection-diffusion equations are introduced to include inertia in the microscopic problem. The approximate inertial terms couple the micro- and macroscopic fields. Here, this coupling is solved numerically using an iterative fixed-point procedure. We compare the resulting models against full-scale simulations, with a good agreement both in terms of averaged values across the membrane and far-field values. Eventually, we develop a strategy based on unsupervised machine learning to improve the computational efficiency of the iterative procedure. The extension of homogenization toward weak-inertia flow configurations as well as the performed data-driven approximation may find application in preliminary analyses as well as optimization procedures toward the design of filtration systems, where inertia effects can be instrumental in broadening the spectrum of permeability and selectivity properties of these filters.

physics.flu-dyn↗

arXiv2017

A computational continuum model of poroelastic beds

Despite the ubiquity of fluid flows interacting with porous and elastic materials, we lack a validated non-empirical macroscale method for characterizing the flow over and through a poroelastic medium. We propose a computational tool to describe such configurations by deriving and validating a continuum model for the poroelastic bed and its interface with the above free fluid. We show that, using stress continuity condition and slip velocity condition at the interface, the effective model captures the effects of small changes in the microstructure anisotropy correctly and predicts the overall behaviour in a physically consistent and controllable manner. Moreover, we show that the performance of the effective model is accurate by validating with fully microscopic resolved simulations. The proposed computational tool can be used in investigations in a wide range of fields, including mechanical engineering, bio-engineering and geophysics.

physics.flu-dyn↗