An Analysis of Spin-Diffusion Dominated Ferrofluid Spin-Up Flows in Uniform Rotating Magnetic Fields
S. Khushrushahi, A. Guerrero, C. Rinaldi, and M. Zahn
Massachusetts Institute of Technology, Cambridge, MA
Univeridad Industrial de Santander, Bucaramanga, Colombia
University of Puerto Rico, Mayaguez, Mayaguez, PR
This work analyzes the spin-diffusion dominated explanation for spin-up bulk flows in ferrofluid filled cylinders, with no free surface, subjected to a uniform rotating magnetic field. COMSOL results are compared to experimental results and analytical results. Simulating ferrofluid spin-up flows have many subtleties, especially when using a single domain region to model the ferrofluid ...
T. Burnett, and D. Lower
CH2M-WG Idaho, LLC
The Idaho Cleanup Project at the Idaho National Laboratory
Idaho Falls, ID
Hot Isostatic Pressing (HIP) has been selected as a means of treating calcined high level waste (HLW). The process combines high temperature and pressure to densify the HLW in to a mineral similar to the geologic formulation of granite. This study uses COMSOL to predict densification and shape deformation of a stainless steel can filled with HLW. Two approaches were used to model ...
S. Loire, and P. Kauffmann
University of California
Santa Barbara, CA
Recently, electrokinetic flows have raised the interest of the scientific community. Driving flow with an electric field leads to promising applications for mixing, concentration, pumping application in lab on chips. However, current models are still inaccurate and don\'t fit the measures. The simple decoupled model developed by Ramos et al does not predict velocities for all parameters. ...
Modeling and Simulation of Artificial Core-Shell Based Nanodielectrics for Electrostatic Capacitors Applications
D. Musuwathi Ekanath, N. Badi, and A. Bensaoula
Center for Advanced Materials, University of Houston, Houston, TX
Dept. of Physics, University of Houston, Houston, TX
The need for high storage capacitors led to the development of polymer based capacitors. Polymers have high processability, mechanical flexibility, electrical breakdown strength and compatibility with printed circuit board (PCB) technologies; but usually have very low permittivity (K). In COMSOL Multiphysics software, the AC/DC module is selected and the In-plane electric currents are applied ...
M. Gobbert, and D. Trott
University of Maryland Baltimore County
Many application problems have non-smooth forcing terms, such as the Dirac delta function. The convergence order for the FEM solution is limited by the regularity of the solution in this case. This paper presents information on the techniques needed in COMSOL 4 to enable FEM convergence studies for time-dependent problems of this type, including how to correctly implement the Dirac delta ...
COMSOL Modeling of Groundwater Flow and Pollutant Transport in a Two-Dimensional Geometry with Heterogeneities
M. Gobbert, M. Whitmore, B. Peercy, M. Baker, and D. Trott
University of Maryland Baltimore County
The Delmarva Peninsula is located on the East Coast of the United States, between the Chesapeake Bay and Atlantic Ocean. Industrial farming in the Delmarva Peninsula leads to levels of nutrients nitrogen, which grossly exceed natural levels and greatly impair the health of the bay. The main source of water carrying excess nitrogen to streams is groundwater. We use the software package COMSOL ...
L. Graber, J. Kvitkovic, T. Chiocchio, M. Steurer, S. Pamidi, and A. Usoskin
Center for Advanced Power Systems, Florida State University, Tallahassee, FL
Bruker Energy & Supercon Technologies Inc., Billerica, MA
Finite element models, which include the shielding characteristics of superconductors are often complex and would currently not allow us to study 3D models of devices of complex geometry such as fault current limiters. We propose instead a model based on variable electric conductivity, which is suitable to simulate magnetic field characteristics of inductive superconducting fault current ...
J. Strong, and C. Washburn
Sandia National Laboratories
The newly emerging field of carbon-based MEMS (C-MEMS) attempts to utilize the diverse properties of carbon to push the performance of MEMS devices beyond what is currently achievable. Our design employs a carbon-carbon composite using nano-materials to build a new class of MEMS accelerometer that is hyper-sensitive over a dynamic range from micro-G to hundreds of G’s – far surpassing the ...
P. Mikulski, K. Mcilhany, and R. Malek-Madani
United States Naval Academy
Here we present and discuss numerical solutions to the paraxial wave equation using COMSOL (2D, PDE, General Form, time-dependent analysis). Ultimately, the goal is to extend this treatment of free-space beam propagation to the case of propagation through a medium that is non-uniform and subject to non-linear effects where the beam itself is modifying the properties of the medium in which it is ...
P. Lin, C. Chang, H. Huang, and B. Zheng
Mechanical and Aerospace Eng., Rutgers, The State University of New Jersey, Piscataway, NJ
FTR Systems (Shanghai) Inc., Shanghai, China
PolarOnyx, Inc., San Jose, CA
School of Mechatronics Eng., University of Electronic Science and Technology of China, Chengdu, China
The heat sink designs using impinging liquid jets, which form stagnation flows, feature uniform heat transfer coefficients, and provide thin thermal boundary layers, are studied to reduce the heat from GPUs. Three different designs using central, micro, and uniform-cross-section (UCS) central jets are studied and simulated in COMSOL. The efficiency factors, defined as the ratio of total ...