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Pablo Diez-Silva

Publications and source records attributed to Pablo Diez-Silva.

2 recordsLinked to original sources

libMobility: A Python library for hydrodynamics at the Smoluchowski level

Effective hydrodynamic modeling is crucial for accurately predicting fluid-particle interactions in diverse fields such as biophysics and materials science. Developing and implementing hydrodynamic algorithms is challenging due to the complexity of fluid dynamics, necessitating efficient management of large-scale computations and sophisticated boundary conditions. Furthermore, adapting these algorithms for use on massively parallel architectures like GPUs adds an additional layer of complexity. This paper presents the libMobility software library, which offers a suite of CUDA-enabled solvers for simulating hydrodynamic interactions in particulate systems at the Rotne-Prager-Yamakawa (RPY) level. The library facilitates precise simulations of particle displacements influenced by external forces and torques, including both the deterministic and stochastic components. Notable features of libMobility include its ability to handle linear and angular displacements, thermal fluctuations, and various domain geometries effectively. With an interface in Python, libMobility provides comprehensive tools for researchers in computational fluid dynamics and related fields to simulate particle mobility efficiently. This article details the technical architecture, functionality, and wide-ranging applications of libMobility. libMobility is available at https://github.com/stochasticHydroTools/libMobility.

cond-mat.soft

Three-dimensional Optical Reconstruction of colloidal electrokinetics via multiplane imaging

Sorting, filtering, moving and controlling colloidal particles is crucial in many fields, ranging from chemistry to biology and physics. Dielectrophoresis is an outstanding tool for the manipulation of small particles by AC electric fields, due to its high selectivity and the absence of the need for labels. We use a new theoretical-experimental approach to study the dynamics of fluorescently labeled polystyrene nanoparticles of 200 nm under positive and negative dielectrophoresis conditions. Our multiplane widefield microscopy technique combined with single particle tracking offers real-time ($>$ 100 fps) superresolved visualization of colloidal dynamics in three spatial dimensions. This real-time 3D imaging technique allows the reconstruction of superresolved trajectories, enabling the visualisation of local forces with unprecedented detail. To interpret this data, a dedicated multiscale modeling approach was developed, targeting a direct comparison between theory and experiment. In the current model DEP and electro-osmotic forces were considered. Under positive DEP conditions, this resulted in a very good agreement with experiment. Under negative DEP conditions, the agreement is less clear, indicating the importance of other effects. This illustrates the potential of this combined 3D imaging and modeling approach to validate and refine our theoretical understanding of AC field induced colloidal dynamics. This framework is broadly applicable to other complex fluid or microfluidic motion.

cond-mat.soft