www.polito.itPietro Asinari

Professor of Heat and Mass Transfer
Multi-scale Modeling Lab - SMaLL
E-mail: pietro.asinari AT polito.it
Mail: Department of Energy,
Politecnico di Torino,
Corso Duca degli Abruzzi 24,
Zip Code 10129, Torino, Italy
Phone: +39 011 090 4434
Fax: +39 011 090 4490




EnerGRID Cluster Facility
Kyoto, 2012

  Last update  

December 23rd, 2016


A comprehensive understanding of molecular transport within nanoporous materials remains elusive in a broad variety of engineering and biomedical applications. In the recent paper published by Matteo Fasano, Elio Chiavazzo and Pietro Asinari on NATURE Communications in collaboration with the Massachusetts Institute of Technology (MIT), experiments and atomistic simulations are synergically used to elucidate the non-trivial interplay between nanopore hydrophilicity and surface barriers on the overall water transport through zeolite crystals. At these nanometre-length scales, these results highlight the dominating effect of surface imperfections with reduced permeability on the overall water transport. A simple diffusion resistance model is shown to be sufficient to capture the effects of both intracrystalline and surface diffusion resistances, thus properly linking simulation to experimental evidence. This work suggests that future experimental work should focus on eliminating/overcoming these surface imperfections, which promise an order of magnitude improvement in permeability. More


The transport of water in nanoconfined geometries is different from bulk phase and has tremendous implications in nanotechnology and biotechnology. In the recent paper published by Elio Chiavazzo, Matteo Fasano and Pietro Asinari on NATURE Communications, the molecular dynamics is used to compute the self-diffusion coefficient D of water within nanopores, around nanoparticles, carbon nanotubes and proteins. For almost 60 different cases, D is found to scale linearly with a parameter which represents the ratio between the confined and total water volumes. As an example, such relationship is shown to accurately predict the relaxometric response of contrast agents for magnetic resonance imaging. This relationship can help in interpreting the transport of water molecules under nanoconfined conditions and tailoring nanostructures with precise modulation of water mobility. More


In the recent paper published by Luigi Ventola, Eliodoro Chiavazzo and Pietro Asinari on Int. J. of Heat and Mass Transfer, experimental evidences are reported on the potential of direct metal laser sintering (DMLS) in manufacturing at and finned heat sinks with a remarkably enhanced convective heat transfer coefficient, taking advantage of artificial roughness in fully turbulent regime. To the best of our knowledge, this is the first study where artificial roughness by DMLS is investigated in terms of such thermal performances. On rough at surfaces, we experience a peak of 73% for the convective heat transfer enhancement (63% on average) compared to smooth surfaces. We propose that heat transfer close to the wall is dominated by eddies with size depending on the roughness dimensions and the viscous (Kolmogorov) length scale. More


In the recent paper published by Eliodoro Chiavazzo, Luigi Ventola and Pietro Asinari on Experimental Thermal and Fluid Science, a sensor for measuring small convective heat flows (<0.2 W/cm^2) from micro-structured surfaces is designed and tested. This sensor exploits the notion of thermal guard and is purposely designed to deal with metal samples made by additive manufacturing, such as direct metal laser sintering (DMLS). Similar works in the literature often have the necessity of maintaining one-directional heat flows along the main dimension of a conducting bar using insulating materials. Such an approach can be critical for small fluxes due to the curse of heat conduction losses along secondary directions. As a result, it is necessary to estimate those secondary fluxes (e.g. by numerical models), thus making the measurement difficult and indirect. On the other hand, depending on the manufacturing accuracy, the present sensor enables to practically reduce at will those losses, with direct measurement of the heat flux. More

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