A. P. Spann , M. J. Hancock ,
 Veryst Engineering LLC., Needham, MA, USA
Recent advances in additive manufacturing enable rapid production of low-cost custom devices.[1-2] Despite modern 3D printers apparent resolutions on the order of tens of microns, for microfluidic applications there are challenges associated with the creation of channels below a few hundred microns, including the removal of support materials. We present two case studies that use COMSOL ...
Hydro-Mechanical Modelling of Infiltration Test for a Bentonite-Sand Mixture: Model Verification and Parameter Identification
M. Hasal, R. Hrtus, Z. Michalec, R. Blaheta
Institute of Geonics AS CR, Ostrava, Czech Republic
The first aim of our work is to create a hydro-mechanical model (HM) of unsaturated fluid flow in bentonite-sand mixture (BSM) MX-80. The second aim is to validate and calibrate the developed model by using the data from a laboratory infiltration test of BSM. The used multi-physics model combines Richards type unsaturated flow with diffusive vapour flow and (nonlinear) elastic response of the ...
P. K. Jain, J. D. Freels
Oak Ridge National Laboratory, Oak Ridge, TN, USA
Engineering design studies of the feasibility of conversion of the High Flux Isotope Reactor (HFIR) from high-enriched uranium to low-enriched uranium (LEU) fuel are ongoing at Oak Ridge National Laboratory as part of an effort sponsored by the U.S. Department of Energy’s Global Threat Reduction Initiative Reduced Enrichment for Research and Test Reactors program. COMSOL Multiphysics® models are ...
L. M. A. Ferreira ,
 CERN, Geneva, Switzerland
In a water based electrolytic polishing process, the formation of molecular hydrogen at the cathode is unavoidable and it can contribute to the formation of surface defects at the anode side. This paper presents the work to model and simulate the molecular hydrogen flow inside radio frequency cavity geometries and compares it with the presence, type and relative position of certain defects in ...
B. Chinè , M. Monno
Laboratorio MUSP, Macchine Utensili e Sistemi di Produzione, Piacenza, Italy
Politecnico di Milano, Dipartimento di Meccanica, Milano, Italy
Instituto Tecnologico de Costa Rica, Cartago, Costa Rica
Introduction: In metal foams production, nucleated gas bubbles expand in a heated metal in a mold, then the foam cool and solidify. Thereby energy, mass and momentum transfer mechanisms are present simultaneously in the system and must be taken into account. Metal foam (Figure 1) can be obtained by foaming a precursor, i.e. a mixing of aluminum (Al) powders with the blowing agent TiH2, placing ...
M. Dagaonkar, V. Kumaran, R. Venkataraghavan, D. C. Franklin
Unilever R&D, Bangalore, Karnataka, India
Dosing a predetermined quantity of one liquid into another, in a controlled fashion, is a process often encountered in a variety of operations at both industrial and laboratory scales. This process becomes a challenging one if it has to be carried out in a continuous mode, without using any dosing pump and if the dosage levels are very small. A possible simple and elegant solution to the problem ...
Materials Synthesis & Integrated Devices, Los Alamos National Laboratory, Los Alamos, NM, USA
Oil and water are immiscible fluids and they tend to separate very easily when introduced into a flow stream from two different sources in a flow loop. This model studies the development of mixture volume fraction in an oil-water-flow loop with 3 different passive mixing schemes: (i) blind-T, (ii) check valve, and (iii) static mixer. Each device produces different levels of mixture homogeneity ...
V. Villani , G. Bella ,
 University "Niccolò Cusano", Engineering Department, Rome, Italy
 University "Niccolò Cusano", Engineering Department, Rome, Italy; University of Rome "Tor Vergata", Rome, Italy
We present a numerical investigation on a metal foam radiator in natural convection. Metal foams are innovative lightweight materials with unique heat dissipation properties. COMSOL Multiphysics® has been used to reproduce experimental data and generate an optimized geometry to maximize the heat flux. Local Thermal Equilibrium approach has been used. The model was generated taking advantage of ...
Numerical Calculation of Effective Density and Compressibility Tensors in Periodic Porous Media: A Multi-Scale Asymptotic Method
C. Lee, M. Leamy, and J. Nadler
School of Mechanical Engineering, Georgia Institute of Technology, Atlanta, GA, USA
Georgia Tech Research Institute (GTRI), Georgia Institute of Technology
A major issue in predicting and controlling (via design) absorption properties of rigid porous media is the determination of the frequency-dependent effective density and compressibility tensors. Unlike previous research efforts which employ in-house and, oftentimes, multiple numerical procedures for determining these two essential tensors, we formulate their solution in terms of a set of micro ...
J.M. Gozalvez-Zafrilla, and A. Santafe-Moros
Universidad Politécnica de Valencia, Valencia, Spain
Flat membrane modules are widely used to study the membrane performance at the laboratory which is influenced by pressure and velocity. Most modules designed for laboratory studies have high pressure drop and abrupt changes of flow direction what yield to lack of uniform flow and pressure uncertainty over the membrane surface. With the aim to minimize these drawbacks, we developed a new module ...