In questa sezione troverete i lavori presentati alle Conferenze mondiali COMSOL. Le presentazioni descrivono ricerche e prodotti innovativi progettati con COMSOL Multiphysics da colleghi di tutto il mondo. I temi delle ricerche presentate abbracciano un'ampia gamma di settori produttivi e aree applicative, in ambito elettrico, meccanico, fluidodinamico e chimico. Lo strumento di Ricerca Rapida vi permetterà di trovare le presentazioni che si riferiscono all'area di vostro interesse.
COMSOL-News-Magazine-2017
COMSOL-News-Magazine-2017-Special-edition-acoustics
COMSOL-News-Magazine-2016

Modeling of a Jecklin Disk for Stereophonic Recordings

G. McRobbie[1]
[1]University of the West of Scotland, Paisley, Renfrewshire, UK

The Jecklin Disk is a sound absorbing disk placed between two omnidirectional microphones. It is used to recreate some of the frequency-response, time and amplitude variations human listeners’ experience, but in such a way that the recordings also produce a useable stereo image through loudspeakers. This paper presents a finite element model able to simulate the effects on sound propagation ...

A COMSOL Model of Damage Evolution Due to High Energy Laser Irradiation of Partially Absorptive Materials

P. Joyce[1], J. Radice[1], A. Tresansky[1], J. Watkins[1]
[1]United States Naval Academy, Annapolis, MD, USA

In this paper we present a transient numerical model of the heat transfer and thermochemical damage evolution in an IR translucent material using COMSOL Multiphysics. The model is evaluated using literature supplied and experimentally determined material properties for carbon black laden PMMA (polymethyl-methacrylate). This variant of PMMA was chosen because it is homogeneous, isotropic, and the ...

Thermo-Fluid Dynamics of Flue Gas in Heat Accumulation Stoves: Study Cases

D. Rossi[1], P. Scotton[1]
[1]University of Padova, Department of Geosciences, Padova, Italy

The research aims to clarify some aspects of the thermo-fluid dynamics of woody biomass flue gas, within the twisted conduit inside the heat accumulation stoves, and exposes also some analysis about the heat transport and heat exchange processes. The high temperature flue gas flows in the conduit, releasing heat to the refractory. The heat stored in the refractory is then released to the ...

Early Stage Melt Ejection in Laser Percussion Drilling

T. Eppes[1]
[1]University of Hartford, Hartford, CT, USA

Laser percussion drilling is widely used in the aerospace industry to produce cooling holes in jet engine components. This process is a thermal, contact-free process which involves firing a sequence of focused optical pulses onto a target material [1-4]. During each optical pulse, the central portion of the target area heats to a liquid then vapor state where the expanding gas produces a recoil ...

Poroelastic Models of Stress Diffusion and Fault Re-Activation in Underground Injection

R. Nopper[1], J. Clark[2], C. Miller[1]
[1]DuPont Company, Wilmington, DE, USA
[2]DuPont Company, Beaumont, TX, USA

Stress and failure in the earth have long been observed to couple to hydrogeology. Poroelastic models, introduced by soil scientists, can account for strong two-way coupling between porous crustal rock formations and their pore fluids. Current efforts to provide new energy resources (water injection in EGS, enhanced oil recovery) and to reduce pollution (CO2 sequestration, deepwell disposal) ...

Numerical Study and Simulation in COMSOL Multiphysics of the Dilution Process during Dust Sampling in Dry Machining

B. Wenga-Ntcheping[1], A. Djebara[1], R. Kamguem[1], J. Kouam[1], V. Songmene[1]
[1]University of Quebec-École de Technologie Supérieure, Montreal, Canada

Dilution’s issue during dry machining have raised the interest’s environmental researchers and engineers. In fact, the sampling of dust emitted during dry machining was a serious problem for air quality evaluation at the workplace. Furthermore, the best sampling of fine and ultrafine particles produced during material cutting, passed through the dilution of high particle concentration (number, ...

Natural Convection Driven Melting of Phase Change Material: Comparison of Two Methods

D. Groulx[1], F. Samara[1], P.H. Biwole[2]
[1]Department of Mechanical Engineering, Dalhousie University, Halifax, NS, Canada
[2]Department of Mathematics and Interactions, University of Nice Sophia-Antipolis, Nice, France

Design of latent heat energy storage systems (LHESS) requires knowledge of heat transfer processes within them, as well as the phase change behavior of the phase change material (PCM) use. COMSOL Multiphysics can be used to model (LHESS). Natural convection plays a crucial role during the charging phase of the LHESS, and methods to incorporate this heat transfer mode within COMSOL simulation ...

Conjugate Heat Transfer

J. Crompton[1], L. Gritter[1], S. Yushanov[1], K. Koppenhoefer[1]
[1]AltaSim Technologies, Columbus, OH, USA

Quenching from high temperature by fluid flow has been analyzed; when no phase transformation occurs heat transfer is a function of conduction and convection. Flow conditions may lead to turbulent flow that affects the heat dissipation over the surface. Analysis of heat transfer with phase transformation is more complex ue to the range of near-wall effects from film boiling, transition boiling, ...

Launcher Design for Chemical Looping Combustion

F. Gao[1], D.W. Greve[1]
[1]Carnegie Mellon University, Pittsburgh, PA, USA

We report here on the use of the COMSOL emw (electromagnetic waves) module in the design of a microwave launcher. This launcher is to be used in a microwave Doppler sensor that is incorporated into a chemical looping combustion system. The launcher is designed in two steps. First, we determine the best mode for launching a wave into air from an overmoded cylindrical waveguide. he TE11 mode is ...

Orientation of Piezoelectric Crystals and Acoustic Wave Propagation

G. Zhang[1]
[1]Clemson University, Clemson, SC, USA

Surface acoustic wave (SAW) devices are commonly used as wireless filters, resonators, and sensors. The confinement of acoustic energy near the surface of a piezoelectric substrate in a SAW sensor makes it highly sensitive for discerning surface perturbation. As sensors, SAW devices have the potential to provide a high-performance sensing platform with capabilities of remote and high-temperature ...