Lawrence Berkeley National Laboratory, Hayward, CA, USA
A pocket-size portable particle size detector for diesel and cigarette smoke aerosols is being designed using particle size and composition methods. Aerodynamics, fluid properties, material composition and aerosol composition are taken into account. Testing methods for the design include using an impactor and virtual impactor with two quartz crystal resonators to determine particle composition ...
M. Giansetti, A. Pezzin, S. Sicardi, G. Rovero
Politecnico di Torino, Torino, Italy
Within wool textile industries, a very important role is played by the so-called finishing processes, in which the textile substrate undergoes steam treatments to achieve the desired level of stabilisation and appearance. Process parameters, namely temperature and moisture content, are known only at the beginning of the process but not in the textile material being treated, where the actual ...
Department of Mechanical Engineering, College of Engineering and Petroleum, Kuwait University, Safat, Kuwait
In this study, numerical simulations of mixing in turbulent flow, subject to a change in density, are performed. Attention is focused on the binary mixing between two streams of fluid in which a variable density step are formed due to a difference in the temperature. This binary mixing problem performed by assuming low Mach number flow. The results demonstrate the variable density effects and ...
Validation for a Quick and Reliable Procedure for Centrifugal Pumps Using Frozen Rotor Methodology in COMSOL Multiphysics®
D. Manenti, G. Tanghetti, R. Roveglia
Metelli SPA, Cologne (BS), Italy
Single stage centrifugal pumps are widely used in several engineering fields such as: room conditioning, energetic cycles, automotive industry, home care, etc. Thus, the possibility of simulate their behaviour, in terms of pressure increase and mass flow rate, is helpful in reducing prototyping costs in the first design stages. The Rotating Machinery Interface is a dedicated tool implemented ...
Numerical Simulation of Carbon Steel Corrosion Exposed to Flowing NaCl Solutions Through an Annular Duct - new
A. Soliz, K. Mayrhofer, L. Caceres
Department of Interface Chemistry & Surface Engineering, Max-Planck-Institut für Eisenforschung, Düsseldorf, Germany
Department of Chemical Engineering, University of Antofagasta, Antofagasta, Chile
A three-dimensional mathematical model under stationary conditions have been established to understand the corrosion of carbon steel cylindrical samples immersed in flowing NaCl solution through an annular duct. The migration, diffusion and convection mass transfer mechanisms were solved using the Nernst–Planck equation coupled to the Navier-Stokes equation. A corrosion model based on the mixed ...
Thermal Natural Convection Simulations with COMSOL Multiphysics® in Comparison with Measurements - new
H. van Halewijn
Fontys University of Applied Physics, Eindhoven, The Netherlands
In a laboratory setup a horizontal rod is heated on one side. By natural convection a stable temperature pattern is developed. Using the Nusselt formulation of the natural convection of cylindrical rods, the temperature distribution can be calculated. Only a good match of the simulations and the measurements can be reached when taking into account all the non-linear physics in the system. In this ...
CFD Analysis of Loss Of Vacuum Accident for Safety Application in Experimental Fusion Reactor Facility
C. Bellecci, P. Gaudio, I. Lupelli, A. Malizia, M.T. Porfiri, R. Quaranta, and M. Richetta
EURATOM, Faculty of Engineering, University of Rome “Tor Vergata”, Roma, Italy
ENEA Nuclear Fusion Tecnologies, Frascati, Roma, Italy
In an experimental nuclear fusion facility dust is generated both during normal machine operations and by macroscopic erosion of the plasma facing materials due to intense thermal loads. This dust can be mobilized by air ingress in case of LOVA (Loss of Vacuum Accident) threaten safety of workers and public. A small facility, Small Tank for Aerosol Removal and Dust (STARDUST), was set up in order ...
D. Song, R. Gupta, and Chhabra
West Virginia University, Morgantown, West Virginia, USA
Indian Institute of Technology, Kanpur, India
Heat transfer from a sphere having a uniform temperature and falling axially in a cylindrical tube filled with an incompressible power-law liquid is numerically investigated. The governing equations for simultaneous flow around a confined sphere and heat transfer to power-law fluids were solved numerically using COMSOL Multiphysics. It was found that the wall effects on the mean Nusselt number ...
Inverse Estimation of the Flow Resistivity Tensor of Open-Cell Foams from Experimental Data and Darcy’s Flow Simulations
C. Van der Kelen, P. Göransson, and N-E.Hörlin
Marcus Wallenberg Laboratory for sound and vibration research, KTH Aeronautical and Vehicle Engineering, Stockholm, Sweden
The flow resistivity tensor, which is the inverse of the viscous permeability tensor, is one of the most important material properties for the acoustic performance of open cell foams, used in acoustic treatments. Due to the manufacturing processes, these foams are most often geometrically anisotropic. This paper discusses the estimation of the flow resistivity tensor using an improvement of a ...
A. Bradji, E. Holzbecher, and M.S. Litz
Department of Mathematics, University of Annaba, Algeria
Georg-August Universität Göttingen, Germany
It is well known that the convergence rate of a numerical model is significantly reduced, when the genuine character of the setting with differential equation and boundary condition is not given anymore. Here we examine the decrease of convergence order for models using COMSOL in which the problem set-up includes a coupling between a 1D and a 2D subdomain. In terms of physics we are dealing with ...