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.

An Examination of Wall Shear Stresses in Curved Arterial Vessels Using Bioresorbable Stents

D. W. Pepper [1], S. Pirbastami [1],
[1] University of Nevada - Las Vegas, Las Vegas, NV, USA

Bioresorbable stents are providing temporary mechanical support to keep a narrowed or blocked coronary artery open and restore the blood flow and will be gradually degraded and resorbed after the healing and remodeling of arterial wall. This new generation of stents has lower rates of restenosis and in-stent thrombosis in comparison with permanently bare-metal stents. Since this new generation ...

超声辅助水下湿法焊接气泡生长规律研究

滕俊博 [1], 孙清洁 [1], 王建峰 [1],
[1] 哈尔滨工业大学(威海)

文章从数值模拟的角度研究了超声辅助水下湿法焊接中超声对自保护药芯焊丝产生的气泡的影响。在水下湿法药芯焊丝电弧焊接(FCAW)中,通过药芯燃烧产生的气泡来保护电弧和熔池,电弧的稳定性因此得到提高。采用了CMOSOL两相流水平集的方法来模拟气泡,采用压力声学来模拟变幅杆振动产生的声波。在变幅杆模拟中,通过在辐射端端面上添加法向加速度,在变幅杆的表面和工件表面添加硬声场条件来形成驻波,通过改变变幅杆端面与工件上表面的距离,计算声辐射功率,从而得到超声谐振高度。在两相流中,首先模拟无超声时气泡的自由上浮过程,再通过在层流中添加体积力即声辐射力来实现声场与流场的耦合。根据模拟情况可以得出轴线上声辐射力、声压的变化规律,以及气泡的上浮规律,从而在实际焊接中控制气泡上浮的速度,更好的保护电弧和熔池,提高焊接质量。

Investigation of Stability of Current Transfer to Thermionic Cathodes

M. Benilov, and M. Faria
Departamento de Física, Universidade da Madeira, Funchal, Portugal

Current transfer from high-pressure arc plasmas to thermionic cathodes may occur in a diffuse mode, when the current is distributed over the front surface of the cathode, or in a spot mode, when most of the current is localized in one or more small areas. Spectra of perturbations of 3D steady-state current transfer to thermionic cathodes of a high-pressure argon arc have been computed in the ...

Electric Field Distributions and Energy Transfer in Waveguide-Based Axial-Type Microwave Plasma Source

H. Nowakowska[1], M. Jasínski[1], and J. Mizeraczyk[1,2]
[1]The Szewalski Institute of Fluid-Flow Machinery, Polish Academy of Sciences, Gdansk, Poland
[2]Dept. of Marine Electronics, Gdynia Maritime University, Gdynia, Poland

In this paper, we examine changes of the electric field distributions in waveguide-based axial-type microwave plasma source (MPS) during tuning procedure. The distributions strongly depend on position of the movable short, so does the wave reflection coefficient of the incident wave. A method of determining tuning characteristics of the MPS consisting in treating the MPS as a two-port network, ...

A Mean Field Approach to Many-particles Effects in Dielectrophoresis

O. Nicotra, and A. La Magna
CNR-IMM Sezione di Catania, Catania, Italy

One of the major applications for dielectrophoresis is the selective trapping and fractionation in lab-on-a-chip devices. Nevertheless, many-particle effects due to high concentrations of biological material around electrodes can cause a rapid decrease of trapping efficiency in dielectrophoretic devices. In this contribution we present a new approach based on a drift-diffusion dynamics to study ...

Hyperbolic Heat Transfer Equation for Radiofrequency Heating: Comparison between Analytical and COMSOL Solutions

V. Romero-García[1], M. Trujillo[2], M.J. Rivera[2], J.A. López Molina[2], and E.J. Berjano[3]
[1]Centro de Tecnologías Físicas Acústica, Universidad Politécnica de Valencia, Valencia, Spain
[2]Dpto. Matemática Aplicada, Instituto Universitario de Matemática Pura y Aplicada, Universidad Politécnica de Valencia, Valencia, Spain
[3]Institute for Research and Innovation on Bioengineering, Universidad Politécnica de Valencia, Valencia, Spain

The Radiofrequency Heating (RFH) is widely employed to heat biological tissue in different surgical procedures. Most models analyze the RFH employing a Parabolic Heat Transfer Equation (PHTE) based on Fourier's theory. The PHTE can be used for problems involving long heating times or low thermal gradients. However, when the problem involves short heating times or extreme thermal gradients it is ...

Inductance of Magnetic Plated Wires as a Function of Frequency and Plating Thickness

T. Graf[1], O. Schälli[1], A. Furrer[1], and P. Marty[1]

[1]Technik und Architektur, Hochschule Luzern, Horw, Switzerland

This paper analyzes the magnetic behavior of electroplated wires. For this purpose the resistance and inductance of single turn loops and coils have been simulated and measured. The measurement is delicate due to the influence of a stray capacitance. We show that the quality factor of magnetic plated loops and coils can be tuned easily by the plating thickness. In addition the quality factor of ...

Long Term Performance Of Borehole Heat Exchanger Fields With Groundwater Movement

S. Lazzari, A. Priarone, and E. Zanchini
DIENCA, University of Bologna, Bologna, Italy

A numerical investigation of the long-term performance of double U-tube borehole heat exchanger (BHE) fields, in the case of non-negligible effects of groundwater movement, is performed by means of COMSOL Multiphysics. Two time periodic heat loads, with a period of one year, are studied: Q1, with a partial compensation between winter heating (principal load) and summer cooling; Q2, with no ...

Modeling Heat and Mass Transfer in Bread During Baking

V. Nicolas[1,2], J.P. Ploteau[1], P. Salagnac[2], P. Glouannec[1], V. Jury[3], and L. Boillereaux[3]
[1]Laboratoire d’Ingénierie des MATériaux de Bretagne – Equipe Thermique et Energétique, Université Européenne de Bretagne, Lorient Cedex, France
[2]Laboratoire d’Etudes des Phénomènes de Transfert et de l’Instantanéité : Agro-industrie et Bâtiment, Université de La Rochelle, La Rochelle Cedex, France
[3]Laboratoire de Génie des Procédés, Environnement, Agroalimentaire, ENITIAA, France

In this paper, we present a first model carried out with COMSOL Multiphysics to model bread baking, considering heat and mass transfer coupled with the phenomenon of swelling. This model predicts the pressures, temperatures and water contents evolutions in the dough for different energy requests. First results obtained are analyzed according to various physical parameters in order to better ...

A Methodology For The Simulation Of MEMS Spiral Inductances Used As Magnetic Sensors

S. Druart, D. Flandre, and L.A. Francis
Université catholique de Louvain - ICTEAM, Louvain-la-Neuve, Belgium

In this paper, a methodology to simulate the electric behavior of spiral inductances is presented and discussed. All the methodology is built with the COMSOL software used with the Matlab scripting interface and then allows performing fully parameterized simulations. The program architecture is explained and is used to simulate two applications. The first calculates the voltage induced by an ...