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.

Heating of Metal Nanoparticles on Absorbing Substrates

L. Bergamini [1], O. Muskens [2], N. Zabala [1], J. Aizpurua [3]
[1] UPV/EHU, Bilbao, Spain; Materials Physics Center and CSIC-UPV/EHU, Donostia-San Sebastian, Spain; Donostia International Physics Center, Donostia-San Sebastian, Spain
[2] University of Southampton, Southampton, UK
[3] Materials Physics Center and CSIC-UPV/EHU, Donostia-San Sebastian, Spain; Donostia International Physics Center, Donostia-San Sebastian, Spain

It is well-known that metal nanoparticles (NPs) excited at the plasmon frequency not only exhibit peculiar optical properties (e.g., a peak in the extinction spectrum, an enhanced electromagnetic near-filed) but also heat up [1]. This phenomenon is highly investigated for medical applications, but it can be exploited also for the realization of optical devices. In our study we use COMSOL ...

Plasmonic Properties of Bimetal Nanoshell Cylinders and Spheres

K. Ehrhold[1], S. Christiansen[1,2], and U. Gösele[1]
[1]Max Planck Institute of Microstructure Physics, Halle, Germany,
[2]Institute of Photonic Technology, Jena, Germany

Plasmonics is a new branch of the fascinating field of photonics and develops concepts to quench light beyond the diffraction limit and enhance electromagnetic fields. These enhancements occur in metals as localized surface plasmon polaritons (LSP) a coupling of the surface density oscillations of the electron gas to the incident light. With threedimensional nano-structures of coinage metals ...

3D Modeling of Plasmon Excitation by Grating

G.G. Gentili[1], S. Pietralunga[2], M. Bolzoni[1]
[1]Politecnico di Milano, Dipartimento di Elettronica e Informazione, Milano, Italy
[2]INFN-CNR, Istituto di Fotonica e Nanotecnologie, Milano, Italy

Grating-assisted optical coupling into long-range modes of strip plasmonic waveguides is analyzed by a 3D numerical simulation with COMSOL Multiphysics. We used the RF Module and its scattering formulation. A comparison with results obtained using the common 2D approximated analysis is shown for the case of 1D grating coupler and input Gaussian beam. Excited diffracted modal field distribution ...

Numerical Simulations of Ion Cyclotron Range of Frequency (ICRF) Wave Fields in a Linear Plasma Device

M. Usoltceva [1], K. Crombé [4], E. Faudot [3], S. Heuraux [3], R. D’Inca [2], J. Jacquot [2], J-M. Noterdaeme [5], R. Ochoukov [2]
[1] Department of Applied Physics, Ghent University, Belgium; Max-Planck-Institut für Plasmaphysik, Garching, Germany; Université de Lorraine, Nancy, France
[2] Max-Planck-Institut für Plasmaphysik, Garching, Germany
[3] Université de Lorraine, Nancy, France
[4] Department of Applied Physics, Ghent University, Ghent, Belgium; LPP-ERM-KMS, TEC partner, Brussels, Belgium
[5] Department of Applied Physics, Ghent University, Belgium; Max-Planck-Institut für Plasmaphysik, Garching, Germany

Fusion devices (tokamaks, stellarators) require hundreds of millions degree Celsius temperature to reach the plasma state when the fusion reactions start to occur. Ion cyclotron resonance heating (ICRH) is a method of energy transfer to the ions in the plasma from electromagnetic radiation having a frequency equal to the ion cyclotron motion frequency in the presence of a magnetic field. Studies ...

Study of Subwavelength Gratings to Understand Their Polarization Behaviour

M. G. Sridharan[1], A. Prabhakar[2], and S. Bhattacharya[2]
[1]Photonics Group, Department of Electrical Engineering, Indian Institute of Technology Madras, Chennai, India
[2]Department of Electrical Engineering, Indian Institute of Technology Madras, Chennai, India

Phase gratings are used in many applications owing to their high transmission and thus higher diffraction efficiencies. COMSOL is based on finite element modeling and is chosen for 2 reasons; firstly, because it can handle complex 2-D and 3-D geometries and secondly, it can handle the vector nature of these structures. The objective of the design is to compare the results of a commonly used ...

螺旋推进器对提高微波辅助生物柴油生产效率的作用

叶菁华 [1], 朱铧丞 [1]
[1] 四川大学,成都,中国

微波辅助生物柴油生产越来越受到了人们的关注,但是,微波的不均匀加热也影响了微波辅助生物柴油的大规模生产。研究表明,连续流微波加热器可以有效地解决微波辅助生物柴油的批量生产问题[1],螺旋推进器也可以改善加热均匀性,于是仿真带有螺旋推进器的连续流微波加热器的生物柴油生产过程,有利于优化连续流微波加热器的设计,对提高微波辅助生物柴油生产效率有重要的意义。 本文使用了电磁场、旋转机械流、流体传热和化学反应接口。电磁场中的介电系数是关于温度和物质浓度的函数,流体的热参量由流体各组分的质量比等效所得[2]。计算采用步进求解的方法,先在频域求解电磁场,所得的耗散功率代入流体传热,再将求解得到的温度和浓度用于更新介电系数,如此类推直至计算时间结束。 图1为有无螺旋推进器的连续流微波加热器的纵截面温度分布图,可见由于螺旋推进器的搅拌作用,流体的温度均匀性得到了很好的提高 ...

基于等效热模型的三维封装快速热仿真技术

唐旻 [1], 冯强强 [1], 董一琳 [1]
[1] 上海交通大学,上海,中国

近年来,三维系统级封装技术逐渐成为人们的关注焦点,是下一代集成电路封装设计最有发展潜力的实现方案。然而,热管理是系统级封装技术需解决的关键问题。图1是典型的系统级封装结构,包含堆叠芯片、硅通孔、封装基板、热界面材料以及多层凸点结构。若对该结构的所有细节进行建模,将会消耗巨大的计算资源,导致分析效率非常低下。因此,本论文将封装中的硅通孔层以及凸点层等复杂结构进行等效处理,提取它们在水平和垂直方向上的等效热导率以及等效比热容、等效密度等参数。例如,在建模过程中,采用 COMSOL Multiphysics® 传热模块对硅通孔层的水平方向等效热导率进行提取,边界设置如图2所示,通过仿真得到的热源端温度来推导等效热导率。类似地,垂直方向的等效热导率提取如图3所示。经过上述处理,可将封装中的硅通孔层以及凸点层等复杂结构等效为介质均匀的材料,然后再采用 COMSOL 进行整体封装结构的热仿真 ...

Microwave Applicators With Conveyor Belt System

A. Methlouthi, O. Rouaud, and L. Boillereaux
GEPEA-ONIRIS, France

Industrial microwave ovens are widely used in agri-food and chemical applications. Resonant cavities are used to speed up chemical reactions and have the advantage to be small sized and efficient in terms of microwave distribution. These multimode cavities are considered as batch ovens where a small amount of products is treated. Rotating plates are added in the cavities to ensure a homogeneous ...

COMSOL Multiphysics Super Resolution Analysis of a Spherical Geodesic Waveguide Suitable for Manufacturing

H. Ahmadpanahi[1], D. Grabovi?ki?[1], J.C. González[1], P. Benítez[1], J.C. Miñano[1]
[1]Cedint Universidad Politécnica de Madrid, Madrid, Spain

Recently it has been proved theoretically (Miñano et al, 2011) that the super-resolution up to ? /500 can be achieved using an ideal metallic Spherical Geodesic Waveguide (SGW). This SGW is as a theoretical design, in which the conductive walls are considered to be lossless conductors with zero thickness. In this paper, we study some key parameters that might influence the super resolution ...

Designing and Simulating THz Guided Wave Devices Using Finite Element Techniques

L. M. Hayden[1], D. A. Sweigart[1]
[1]Department of Physics, University of Maryland Baltimore County, Baltimore, MD, USA

The generation of terahertz frequency radiation (0.1-10 THz) is an important technological goal due to the use of this non-ionizing radiation to penetrate a wide range of non-conducting materials. One outstanding problem has been the propagation of THz radiation in guided wave devices. Few studies on the construction of efficient THz waveguide devices have been performed. We designed and ...