Artigos Técnicos e Apresentações

Aqui você encontrará apresentações realizadas nas Conferências de Usuários COMSOL de todo o mundo. As apresentações englobam pesquisas e produtos inovadores feitas por engenheiros e cientistas usando o COMSOL Multiphysics. Os tópicos abramgem uma grande gama de indústrias e aplicações, como elétrica, mecânica, escoamento e química. Use a função de busca "Quick Search" para encontrar apresentações na sua área de interesse.

Making Cartograms and Using them for Data Acquisition

P. Mercure[1], and R. Haley[2]
[1]The Dow Chemical Company, Midland, MI
[2]ATM Research, Midland, MI

We demonstrate cartogram construction, where a geographical map is distorted to represent some measure, for example population, while trying to keep the shape of regions recognizable. We then apply this cartogram construction technique to optimize thermocouple locations. A heat generation and conduction model is used initialize the cartogram construction algorithm. A uniform distribution of ...

Optimization of a High-Temperature High-Pressure Direct Wafer Bonding Process for III-V Semiconductors

R. Martin, J. Kozak, K. Anglin, and W. Goodhue
University of Massachusetts Lowell
Lowell, MA

Many optoelectronic devices utilize a heterojunction of a pair semiconducting materials including high-efficiency MEMS devices, solar cells, LEDs, and VCSELs. One fabrication technique which achieves such a device is direct wafer fusion. To optimize the process, COMSOL Multiphysics 4.0 was used to test various geometric configurations of the fixture. 2D and 3D models were created in order ...

Piezoelectric Buzzer Optimization for Micropumps

A. Garcia[1], A. Marcus[1], F. Tejo[1], C. Precker[1], C. Moreira[2]
[1]Universidade Federal de Campina Grande, Campina Grande, PB, Brazil
[2]Instituto Federal de Alagoas, Maceio, AL, Brazil

Piezoelectric buzzers are low cost devices which can be used successfully as actuators in diaphragm-based micro-pumps. The buzzers are piezoelectric wafers (lead-zirconate-titanate-PZT) that are glued on a brass membrane and they are available within different sizes and thicknesses. For the best performance of a diaphragm pump, it is necessary to have a large displacement of the membrane. This ...

Thermal Analysis of Packaged Deep Ultraviolet LEDs

A. Dobrinsky[1], M. Shatalov[1], M. Shur[1], R. Gaska[1]
[1]Sensor Electronic Technology, Columbia, SC, USA

Deep Ultraviolet Light Emitting Diodes (DUV LEDs) are presently operating at a relatively low efficiency, thus large amount of LED driving power is dissipating in heat. Thermal heating degrades LED performance and decreases LED’s lifetime. The degradation of DUV LED devices with temperature increase makes thermal management a key issue for DUV LEDs. We present a thermal analysis of DUV LED ...

Establishing Absorbed Dose Thresholds for Nonlinearities in Water Calorimetry

R.E. Tosh[1], H. Chen-Mayer[1]
[1]National Institute of Standards and Technology, Gaithersburg, MD, USA

The technique of water calorimetry for primary-standard dosimetry of radiotherapy-level ionizing radiation is well established at national metrology institutes around the world, where such a direct realization of absorbed dose establishes the basis for calibrating instruments used for dosimetry in medical settings. The typical calorimeter system uses miniature thermistor beads to measure ...

Modeling of Atmosphere Revitalization

R. Coker[1], J. Knox[1], K. Kittredge[1]
[1]NASA - Marshall Space Flight Center, Huntsville, AL, USA

All spacecraft systems must be minimized with respect to mass, power, and volume. Here, we focus on current efforts to improve system efficiency and reliability for water separation systems to be used on crewed vehicles. These development efforts combine sub-scale systems testing and multi-physics simulations to evaluate candidate approaches. The best performing options will then be ...

Exergy Analysis of a Water Heat Storage Tank

F. Dammel[1], J. Winterling[1], K. J. Langeheinecke[2], P. Stephan[3]
[1]Institute of Technical Thermodynamics, Technische Universität Darmstadt, Germany
[2]IAV, Gifhorn, Germany
[3]Institute of Technical Thermodynamics/Center of Smart Interfaces, Technische Universität, Darmstadt, Germany

A combined heat and power (CHP) plant generates both electricity and useful heat. A heat storage tank enables a decoupling of electricity and heat delivery. In this study a cylindrical hot water storage tank is considered. Charging, holding time and discharging are numerically simulated applying COMSOL Multiphysics 4.2. The performance of the heat storage is evaluated by an exergy analysis. ...

Early Breast Cancer Detection using Patient Symptomatic Breast Images by Finite Element Analysis Aided by COMSOL

Tan Ming Sien[1]
Devendran Perumal[1]
Sri Pooveyninthran[1]
Samavedham Lakshminarayanan[2]
Balu Ranganathan[3]

[1]Department of Chemical and Natural Resources Engineering, University of Malaysia Pahang, Pahang, Malaysia
[2]Department of Chemical and Biomolecular Engineering, National University of Singapore, Singapore, Singapore
[3]Center for Excellence for Fluid Flow Research, University of Malaysia Pahang, Pahang, Malaysia

In this project, we attempted to determine the drug concentration in a breast cancer tumor after a drug has been delivered. We created a COMSOL Multiphysics® finite element model. We investigated the relationship between drug delivery efficiency and parameters such as diffusivity, deepness of the tumor, and the temporal and spatial placement of the transdermal patch that delivers the drug. We ...

Mathematical Modeling of Direct Borohydride Fuel Cells and its Experimental Validation

A. K. R. Paul[1], K. S. Gandhi[2], and A. K. Shukla[3]
[1] Central Electrochemical Research Institute – Madras Unit, CSIR Complex, Taramani, Chennai, Tamil Nadu, India
[2] Department of Chemical Engineering, Indian Institute of Science, Bangalore , Karnataka, India
[3] Solid State & Structural Chemistry Unit, Indian Institute of Science, Bangalore , Karnataka, India

  Direct borohydride fuel cells (DBFCs) use sodium borohydride (NaBH4) as fuel and hydrogen peroxide (H2O2) as an oxidant. A mathematical model encompassing mass balance of ionic species in different regions of the DBFC is developed. Both the oxidation of sodium borohydride and reduction of hydrogen peroxide are assumed to obey Tafel kinetics. This is combined with boundary conditions ...

Gravity-Driven Film Flow: Design of Bottom Topography

C. Heining[1] and N. Aksel[1]

[1]Applied Mechanics and Fluid Dynamics, University of Bayreuth, Bayreuth, Germany

We study the gravity-driven film flow of a Newtonian liquid down an inclined plane. Many applications such as heat- and mass exchangers and evaporators or film coaters require undulated or rippled bottom topographies. In these cases, the interplay of gravity, surface tension and inertia leads to a response of the interface which furthermore strongly depends on the shape of the bottom topography. ...

Quick Search

2721 - 2730 of 3230 First | < Previous | Next > | Last