Here you will find presentations given at COMSOL Conferences around the globe. The presentations explore the innovative research and products designed by your peers using COMSOL Multiphysics. Research topics span a wide array of industries and application areas, including the electrical, mechanical, fluid, and chemical disciplines. Use the Quick Search to find presentations pertaining to your application area.
COMSOL-News-Magazine-2017
COMSOL-News-Magazine-2017-Special-edition-acoustics
COMSOL News Magazine 2017

Looking for the Origin of Power Laws in Electric Field Assisted Tunneling

H. Cabrera[1], D.A. Zanin[1], L.G. De Pietro[1], A. Vindigni[1], U. Ramsperger[1], D. Pescia[1]
[1]Laboratory for Solid State Physics, ETH Zurich, Zurich, Switzerland

A sharp tip approached perpendicular to a conducting surface at subnanometer distances and biased with a small voltage builds a junction across which electrons can be transferred from the tip apex to the nearest surface atom by direct quantum mechanical tunneling. Such a junction is used e.g. in Scanning Tunneling Microscopy (STM). When the distance d between tip and collector is increased ...

Simulation of Helmholtz Resonators for Optical Gas Sensing: Comparison Between Pressure Acoustics and Thermoacoustics - new

B. Parvitte[1], C. Risser[1], R. Vallon[1], V. Zéninari[1]
[1]Université de Reims, Reims, France

Among optical gas sensing methods, photoacoustic (PA) spectroscopy combined with a laser source has proven to be a very robust and sensitive method for trace gas detection. COMSOL Multiphysics® software was used to calculate the frequency response of differential Helmholtz resonator cells in order to optimize the detection limit of PA sensors. Two different kind of simulation were performed: ...

Near-Wall Dynamics of Microbubbles in an Acoustical Trap - new

L. Wright[1], G. Memoli[1], P. Jones[2], E. Stride[3]
[1]National Physical Laboratory, Teddington, UK
[2]University College London, London, UK
[3]University of Oxford, Oxford, UK

Understanding the interactions between microbubbles and surfaces is key to the successful deployment of microbubbles in a range of applications. Two important examples are their use as a drug delivery mechanism, and their potential use of acoustically-driven bubbles as microscale sensors. Drug delivery with bubbles involves sonication at high frequency close to a boundary, and sensing with ...

Modeling of Asphaltenes and Oil Shale Pyrolysis - new

J. P. Mmbaga[1], F. Munoz[2], S. Dhir[1], R. Gupta[1], R. E. Hayes[1], M. Toledo[2]
[1]University of Alberta, Edmonton, AB, Canada
[2]Departamento de Ingenieria Mecanica, Universidad Tecnica Federico Santa Maria, Valparaiso, Chile

Pyrolysis is a key step in the conversion of carbonaceous materials into useful products. In this study, we investigate the pyrolysis of asphaltene and oil shale, both experimentally and numerically. COMSOL Multiphysics® software is used to model the combined effects of fluid flow in porous media, mass transfer of species, heat transfer, and reaction kinetics. Gas evolution and the porosity ...

Conductivity Estimation of Breast Cancer Using COMSOL® Modeling of Microwave Scattering and Frechet Mean Estimate of Covariance - new

A. Jeremic[1], E. Khoshrowshahli[2]
[1]Electrical & Computer Engineering, McMaster University, Hamilton, ON, Canada
[2]Biomedical Engineering, McMaster University, Hamilton, ON, Canada

Breast cancer detection is one of the most important problems in health care and it is second most frequent cancer according to WHO. It is recommended that women over fifty or even younger in some cases do a screening test every two years. Besides clinical breast examination, there are number of imaging methods used for this purpose, such as mammography, ultrasound and MRI. Among them, ...

Tuning Sensitivity to Ectopeptidase Rates in the Rat Hippocampus Using Numerical Simulations - new

Y. Ou[1], S. Weber[1]
[1]University of Pittsburgh, Pittsburgh, PA, USA

We have created and optimized a multiphysics model in COMSOL Multiphysics® software that studies sensitivity to ectopeptidase rates in the rat hippocampus. Ectopeptidases are membrane-bound enzymes whose catalytic domains face the extracellular space (ECS) (Figure 1). They have traditionally been accepted to inactivate peptides from the ECS[1]. Recently, not only can these enzymes activate ...

Electron Drift in Xe Gas

T. J. Berger [1],
[1] Department of Physics, Applied Physics, and Astronomy, Rensselaer Polytechnic Institute, Troy, NY, USA

The XENON Dark Matter Experiment utilizes ultra-pure xenon (Xe) as a target for particle interaction in the effort to detect dark matter particles. To measure the purity of Xe, a gas purity monitor (GPM) is being developed which drifts electrons through Xe gas to detect impurities that contribute to charge attenuation. An axially-symmetric model is used to simulate the electric field generated ...

浅海声场建模预报

刘佳琪 [1], 朴胜春 [2], 唐骏 [2]
[1] 哈尔滨工程大学,哈尔滨,黑龙江,中国
[2] 挪威科技大学,特隆赫姆,挪威

海洋覆盖了地球表面百分之七十以上的面积,其中蕴藏着丰富的生物矿产资源,日益受到世界各国的重视。声波作为海水中传输信号的唯一载体,在浅海波导中的传播受海底和海面影响很大,当声波在浅海波导中发生折射反射和散射时,如何预报复杂海底边界条件下浅海中的传播特性对海洋开发有重要意义。针对含有声速剖面的沉积层海底、楔形海底及实际弹性海底,利用有限元理论,对二维浅海声场的传播损失进行数值模拟。应用 COMSOL Multiphysics® 软件的声压接口和声结构耦合接口,把地形数据导入软件模拟真实海底的地形。把浅海波导简化成分层矩形,信号源以点声源的形式向外发射单频信号,在模型定义处添加完美匹配层模拟无限远距离处声压场情况;对于含有声速剖面情况的波导问题,在 COMSOL 中可以较为便捷地以添加内插函数的形式进行仿真,与其他声场建模软件形成对比,突显有限理论元理论计算浅海传播损失的优势 ...

Simulation of the Acoustic Environment for the Manufacture of Graded Porosity Materials by Sonication

C. Torres-Sanchez, and J. R. Corney
University of Strathclyde, United Kingdom

Many materials require functionally graded cellular microstructures whose porosity is engineered to meet specific requirements of diverse applications. It has been shown in previous work that the bubble growth rate of a polymeric foam can be influenced by the surrounding acoustic environment and, once solidified, produce a solid of graded porosity. Motivated by the desire to create a flexible ...

Simulation of C-MEMS Based Enzymatic Biofuel Cell

Y. Parikh, V. Penmatsa, J. Yang, and C. Wang

Department of Mechanical & Material Science Engineering, Florida International University, Miami, FL, USA

An Enzymatic Biofuel Cell (EBFC) converts the chemical energy in biological fuels into electricity. In this work, we optimize the performance of the Carbon-Micro Electro Mechanical system in an EBFC by using COMSOL Multiphysics. With a simple model, we realized that most of the glucose reacts with enzymes at the top of the electrode posts, while the bottoms of the posts remain deficient of the ...