M. Bachmann, V. Avilov, A. Gumenyuk, and M. Rethmeier
BAM Federal Institute for Materials Research and Testing
The article deals with the magnetically-supported high-power full-penetration laser beam welding of aluminum. A stationary simulation was conducted accounting for the effects of natural convection, Marangoni convection and solid-liquid phase transition as well as an electromagnetic volume source term. An ac magnet below the weld specimen induces eddy currents. Consequently, Lorentz forces occur ...
Using COMSOL Multiphysics® Software and the Application Builder for Neutron Transport in Discrete Ordinates
C. J. Hurt , J. D. Freels ,
 University of Tennessee, Knoxville, TN, USA
 Oak Ridge National Laboratory, Oak Ridge, TN, USA
Introduction: The numerical solution to the neutron transport equation is employed to study a variety of problems in nuclear engineering applications, including for both eigenvalue and fixed source studies. Historically, multiphysics analysis at the HFIR has utilized these solutions to include thermal-structural and thermal hydraulic physics with a weak coupling due to the limited ...
Understanding the Magnetic Field Penetration in Mesoscopic Superconductors via COMSOL Multiphysics® Software - new
I. G. de Oliveira
Universidade Federal Rural do Rio de Janeiro, Seropédica, RJ, Brazil
Introduction: One of the main characteristic of the superconductors is its diamagnetic response of applied magnetic fields. The superconductors refuse the penetration of magnetic field into its interior, it is the well know Meissner effect, B=0 into the superconductor sample. However when the applied field reach a determined value, the magnetic field can enter. There are two different ways of ...
S. Durgam , S. P. Venkateshan , T. Sundararajan ,
 Indian Institute of Technology Madras, Chennai, India
This paper deals with the numerical study of optimal distribution of rectangular heat sources populated on a substrate board for electronic cooling. The simulations are performed for laminar forced convection conjugate heat transfer with vertical orientation of substrate board. The laminar forced convection - conjugate heat transfer simulations are carried out using COMSOL Multiphysics® with ...
Finite Element Analysis of Transient Ballistic-Diffusive Heat Transfer in Two-Dimensional Structures - new
S. Hamian, T. Yamada, M. Faghri, K. Park
University of Utah, Salt Lake City, UT, USA
Lund University, Lund, Sweden
University of Rhode Island, Kingston, RI, USA
For the last two centuries, the conventional Fourier heat conduction equation has been used for modeling a diffusive nature of macroscale heat conduction by considering the energy conservation and Fourier's linear approximation of heat flux. However, it cannot accurately predict heat transport when the length scale is comparable to or smaller than the mean free path of thermal energy carriers or ...
V. B. Math, B. G. Sheeparamatti, A. C. Katageri
Basaveshwar Engineering College, Bagalkot, Karnataka, India
This paper presents a unique design of MEMS based 4-bit shift register that perform shifting operation same as logic devices that are composed of solid-state transistors. The MEMS shift register design inherits all the advantages from MEMS switches and thus is expected to have more applications. One unique feature of this device is that it can perform all types of shifting mechanisms, but with ...
Institute of Applied Mechanics, Poznan University of Technology, Poznan, Poland
An external magnetic field imposed on a ferrofluid with a temperature gradient, results in a non-uniform magnetic body force, which leads to a form of heat transfer called thermomagnetic convection. A magnet placed near the device will always attract the colder ferrofluid more than warmer. Viscous, two-dimensional, laminar and incompressible ferromagnetic fluid flow, under the influence of a ...
J. T. Andrews, R. Choubey, O P Choudhary, N. Malviya, A. Patel, M. Kumar, S. Chouksey, J. Solanki
National MEMS Design Center, Department of Applied Physics, Shri G S Institute of Technology & Science, Indore 452003 MP, India
A logic gate performs a certain Boolean logic operation on one or more logical inputs and produces a single logical output. The logic values are either “true” or “false.” Logic gates are bistable devices, that is, they may yield one of these two possible stable outputs. The NAND logic is a universal gate; any logic operation can be performed with various combinations of NAND logics. Many ...
E. C. Santos, J. H. Sales, C. Lima
Universidade Estadual de Santa Cruz, Ilhéus, BA, Brazil
Instituto Federal da Bahia, Irecê, BA, Brazil
This paper compares the efficiency of a vertical solar dryer vis-à-vis the traditional drying method by the means of a computer simulation. The said program considers geometric, thermal and mechanical effects so as to simulate heat transfer via conduction, convection and radiation. We later ran additional tests with simulated data on the greenhouses(traditional method) so as to compare the ...
湛利华 , 李自强 ,
复合材料帽型加筋结构在航空航天领域得到了广泛应用，硅橡胶芯模是实现其共固化成型的关键工装之一。预浸料固化加热过程中硅橡胶的热膨胀需要通过预制调型孔来消除，以保证帽型加筋结构的成型质量。本文通过 COMSOL Multiphysics® 建立了硅橡胶芯模预制调型孔热力耦合有限元分析模型（图 1），采用传热和结构力学模块对不同结构硅橡胶芯模进行计算机仿真，得出实现复合材料帽型加筋结构形性协同制造的硅橡胶芯模预制调型孔的最佳尺寸范围（图 2）。综合分析硅橡胶芯模受热膨胀的可能影响因素，建立了考虑体积修正系数的预制调型孔计算模型。进一步利用有限元方法回归了芯模预调制型孔体积修正系数，利用回归出的修正系数对不同截面尺寸的帽型结构进行仿真验证，从而确定了较准确地预制调型孔的理论计算模型（图 3）。最后，通过实验验证了该数学模型及有限元分析方法的正确性，为制造复合材料帽型加筋结构提供了理论与实验依据 ...