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.

Numerical Simulation of Thermal Runaway in a THz GaAs Photoconductor - new

S. Sarodia[1,2], W. Zhang[2], E. Brown[2]
[1]Centerville High School, Dayton, OH, USA
[2]Wright State University, Dayton, OH, USA

Ultrafast terahertz photoconductor devices, especially photomixers, are usually limited in output power by device failure thought to be caused by excessive temperatures. Therefore, understanding of thermal breakdown is essential to the study of device reliability and failure of photoconductors. We performed a series of simulations to determine the electronic and thermal thresholds responsible ...

Dielectric Adaptive Optical Gels

R. Eisenschmid [1],
[1] OPTIMA pharma GmbH, Schwäbisch Hall, Germany

Adaptive Optics is common sense, since many people use digital cameras with electromechanical iris actors on elastic autofocus lenses. This project tries to create a COMSOL Multiphysics based mathematical model of adaptive optics with electrostatically induced deformation of dielectric gels. Upper and lower sides of a lens (dielectric conductive gel) are coated by transparent conductive films, i ...

Coupling Picosecond Terahertz Pulses to a Scanning Tunneling Microscope

P. H. Nguyen [1], C. Rathje [2], G. J. Hornig [1], V. Jelic [1], C. Ropers [2], F. A. Hegmann [1],
[1] University of Alberta, Edmonton, AB, Canada
[2] 4th Physical Institute, University of Göttingen, Göttingen, Germany

Probing ultrafast processes over subpicosecond and picosecond time scales provides fundamental insight into the nature of materials. We have experimentally demonstrated terahertz (THz)-pulse-induced tunneling in a scanning tunneling microscope (THz-STM) to image surfaces with simultaneous nanometer spatial resolution and subpicosecond time resolution [1]. However, the exact mechanism by which ...

Comparison of Magnetic Barkhausen Noise Tetrapole and Dipole Probe Designs

P. R. Underhill [1], T. W. Krause [1],
[1] Department of Physics, Royal Military College of Canada, Kingston, ON, Canada

COMSOL Multiphysics® software is used to understand the difference in behaviour of two Magnetic Barkhausen Noise (MBN) probes. The dipole probe has to be physically rotated to sample the angular distribution of the MBN. The tetrapole probe uses vector superposition to rotate the magnetic field without probe motion. Using the AC/DC Module and non-isotropic material properties, it was found that, ...

Effect of Antenna Deformation on Performance

J. Persad [1], S. Rocke [1], A. Abdool [1], D. Ringis [1],
[1] Department of Electrical and Computer Engineering, University of the West Indies, St. Augustine, Trinidad and Tobago

Ubiquitous, unobtrusive wearable computing has tremendous potential for impacting many applications including medical, personal entertainment and surveillance. Advances in the underlying technology have allowed for consistent reduction in the size and weight of emerging solutions, with increasing subsystem integration. A key component for the realisation of these systems is the short and long ...

Simulation of Gas Injection with the Level Set Method

J. E. Rivera-Salinas [1], A. Cruz-Ramírez [1]
[1] National Polytechnic Institute - ESIQIE, Department of Metallurgy and Materials, Mexico

The physical mechanisms that operate in gas injection are complex, since the bubble formation at submerged orifices involves a wide range of length and time scales, bubble coalescence occurs, rapid pressure variations around the gas bubble produce the wobbling of the bubble, as well as the high velocities involved in the bubble bursting phenomenon on the free surface, among the others. In this ...

An Application Built with the COMSOL Multiphysics® Software for Managing Computational Sequences in Thermal Fluid Applications

G. Petrone [1], C. Barbagallo [1],
[1] BE CAE & Test, Catania, Italy

An app built with the COMSOL Multiphysics® software allows both expert and beginner users to carry out parametric simulations thanks to flexible and user-friendly customized interfaces. Many people, with or without expertise in numerical analysis, can now access, exploit and share simulation tools, representing a new frontier in virtual prototyping. The investigated topic concerns an industrial ...

Study of Fracture Parameter for Curved Cracked Bimodular Flexural Specimen Using COMSOL Multiphysics® Software

A. Bhushan [1], S.K. Panda [1],
[1]Indian Institute of Technology (BHU) Varanasi, Uttar Pradesh, India

The formulation of bimodular stress field is based on stress dependent elasticity and the simulations have been carried out using commercial finite element software COMSOL Multiphysics® software. The complexity of the problem is enhanced due to adding bimodular stress field in the evaluation of complex J-integral ( ˆ F J ) for curve cracked geometry subjected to flexural loading. The complex J ...

Influence of Non-Newtonian Blood Viscosity on Wall Pressure in Right Coronary Arteries with Serial Stenoses

B. Liu [1]
[1] Monmouth University, West Long Branch, NJ, USA

Three dimensional mathematical models are developed to simulate the blood flows in patient specific right coronary arteries with two stenoses. Simulations are carried out with various flow parameters under physiological conditions. Both Newtonian and non-Newtonian blood viscosity models are applied in the simulations to examine the influence of non-Newtonian viscosity of blood on the wall ...

旋转器结构单元尺寸对其工作带宽的影响

屈治国 [1], 张秀海 [1],
[1] 热流科学与工程教育部重点实验室,西安交通大学能动学院,西安,中国

超材料是一类具有天然材料所不具备的特殊性质的材料[1-3]。近年来,有学者开始研究超材料对波的旋转效应,这一研究有着工程应用价值。江雪等[4]设计并实验验证了一种声场旋转器。江雪等[5]进一步研究了声场旋转器整体尺寸大小对其工作带宽的影响及声场旋转器中心处的旋转角度与其结构单元长度的关系。但未见声场旋转器结构单元尺寸对其工作带宽影响的研究。 本文采用 COMSOL Multiphysics® 的声学模块和结构力学模块模拟图1的俯视二维结构,采用完美匹配层以获得更好的模拟结果。 本文模拟了5个声场旋转器在不同频率下的声场,发现随着长方体结构单元长宽比的增加,尽管声场旋转器在低频仍能工作,但可以工作的高频频率是下降的,即声场旋转器的工作带宽是变窄的。为了确定声场旋转器的高频工作截止频率,本文采用二分法确定声场旋转器#1-#5的高频截止频率 ...