A well-corroborated numerical methodology ensuring reproducibility in the modeling of pharmaceutical aerosols deposition respiratory system via CFD-DEM simulations within RANS framework is currently missing. Often, inadequately clarified assumptions and approximations lack evidences on their quantitative impact simulated phenomenology, make a direct comparison among different theoretical studies limited number experiments very challenging task. Here, with ultimate goal providing critical...

Abstract Results from large-eddy simulations of short-range dispersion a passive scalar point source release in an urban-like canopy are presented. The computational domain is that variable height array buildings immersed pressure-driven, turbulent flow with roughness Reynolds number ${\mathit{Re}}_{\tau } = 433$ . A comparative study several cases shows the changes plume behaviour for different mean directions and locations. analysis results focuses on utilizing high-fidelity datasets to...

The reliability and accuracy of numerical models computer simulations to study aerosol deposition in the human respiratory system is investigated for a patient-specific tracheobronchial tree geometry. A computational fluid dynamics (CFD) model coupled with discrete elements methods (DEM) used predict transport aerosol. results are compared experimental data available literature quantify impact modeling parameters assumptions. Even if total compares very well reference data, it clear from...

Views Icon Article contents Figures & tables Video Audio Supplementary Data Peer Review Share Twitter Facebook Reddit LinkedIn Tools Reprints and Permissions Cite Search Site Citation Michele Penza, Domenico Suriano, Gennaro Cassano, Riccardo Rossi, Marco Alvisi, Valerio Pfister, Livia Trizio, Magda Brattoli, Gianluigi De Gennaro; A Gas Sensor Array For Environmental Air Monitoring: Study Case Of Application Artificial Neural Networks. AIP Conf. Proc. 6 September 2011; 1362 (1): 205–206....

Trailing edge slot film cooling is a widely used active scheme for turbine blade trailing edges. Current Reynolds-Averaged Navier–Stokes (RANS) models are known to significantly overpredict the adiabatic effectiveness of these configurations. It shown that this overprediction due in part breakdown Reynolds analogy between turbulent shear stress and scalar transport near wall region. By examining previously reported direct numerical simulation (DNS) results wall-mounted cube cross flow, it...

The present work aims to assess whether a standard numerical simulation (RANS-VOF model with k − ϵ closure) can adequately experimental measurements obtained in dam physical model. investigation is carried out on the Sa Stria Dam, roller compacted concrete gravity currently under construction Southern Sardinia (Italy). original project, for which was simulated, included downstream secondary dam. However, due both economic and technical reasons, may not be built. Hence, it important flood...

Reactivity-controlled compression ignition combustion has proved to be effective in reducing the pollutant emissions and fuel consumption four-stroke internal-combustion engines. The application of this mode port-controlled crankcase-scavenged two-stroke engines also seems promising avoid short-circuiting fresh charge take advantage intrinsic residual exhaust gas. Accordingly, a computational study small-bore dual-fuel direct-injection reactivity-controlled engine was made including fluid...

Homogeneous-charge, compression-ignition (HCCI) combustion is triggered by spontaneous ignition in dilute homogeneous mixtures. The rate must be reduced suitable solutions such as high rates of Exhaust Gas Recirculation (EGR) and/or lean HCCI considered to a very effective way reduce engine pollutant emissions, however only few production engines have been built. currently cannot extended the whole operating range, especially loads, since use EGR displaces air from cylinder, limiting mean...

Numerical experiments by Large-Eddy Simulation (LES) are performed on the turbulent flow and mixing of a passive scalar past square cylinder. A Reynolds number 21 400 is selected, matching available measurements from laser-doppler velocimetry (LDV), released point source downstream comparative study numerical results against LDV data presented in order to validate present LES methodology, where sub-grid stresses estimated via WALE similarity mixed model coupled with newly developed...

We present a numerical study of passive scalar dispersion in turbulent separated flows to establish the predictive capabilities algebraic flux models against standard eddy-diffusivity representation. The from point source over wavy wall is initially investigated carefully evaluate using accurate DNS data. roof-top release plume wall-mounted cube boundary layer then presented prove that can also be applied successfully atmospheric at street-scale. Despite similarities with gradient-diffusion...

In this paper, we present the numerical analysis of fully developed ow and heat transfer in pipes equipped with twisted-tape inserts laminar to transitional flow regime. The Reynolds number ranges from 210 3100 based on pipe diameter, whereas Prandtl working fluid, a 40% mixture water ethylene glycol, is about 45 at average film temperature. study carried out via Scale Adaptive Simulations (SAS) where k-ω SST model employed for turbulence modeling. Using SAS low-dissipation discretization...

Numerical experiments by Large-Eddy Simulation (LES) are performed on the turbulent flow and mixing of a passive scalar past square cylinder. A Reynolds number 21 400 is selected, matching available measurements from laser-doppler velocimetry (LDV), released point source downstream comparative study numerical results against LDV data presented in order to validate present LES methodology, where subgrid stresses estimated via WALE similarity mixed model coupled with newly developed...

A numerical multi-scale method for the analysis of heat exchangers is presented. In present work this methodology has been used to analyze Ducati 999 motorbike cooling system. order compute flowfield around vehicle and obtain velocity distribution inside volume, a finite volume model adopted. distributed then exchange process that takes place into exchanger different distributions constant liquid inlet temperature. The results are described with particular emphasis on airflow across thermal...