Use of Simulation in the Development of Next-generation Measurement Standards for Radiation Dosimetry
R. E. Tosh, H. Chen-Mayer
NIST, Gaithersburg, MD, USA
Calibration of field instruments used in radiation treatment clinics is currently traceable to NIST primary standards via protocols involving static, flat-field radiation beams. By contrast, radiation beams prescribed for treating cancer incorporate temporal and spatial modulation strategies in order to maximize dose to the tumor while sparing healthy tissue. Differences in the detector ...
A. Travis, K. Ekici, J. Freels
The University of Tennessee, Knoxville, TN, USA
Oak Ridge National Laboratory, Oak Ridge, TN, USA
A model utilizing interdimensional variable coupling is presented for simulating the thermal hydraulic interactions of the High Flux Isotope Reactor (HFIR) core at Oak Ridge National Laboratory (ORNL). The model’s domain consists of a three-dimensional fuel plate and a two-dimensional coolant channel slice. In simplifying the coolant channel, the computational cost and solution time are both ...
Combustion Study of DDGS Char from Steam-O2 Blown CFB Gasifier and Charcoal Using Thermogravimetric Analysis and COMSOL Multiphysics®
X. Meng, W. de Jong, A.H.M. Verkooijjen
TU Delft, Delft, The Netherlands
To obtain reliable kinetic data for the modeling of Dried Distiller’s grains with Soluble (DDGS) gasification using a 100 kWth steam-O2 blown circulating fluidized bed (CFB) gasifier, the combustion behavior of partially gasified residual DDGS char and pure charcoal as a comparison has been investigated using thermogravimetric analysis (TGA). Two conversion models, volume reaction model (VRM) ...
N. Garcia-Polanco, J. Capablo, J. Doyle
Whirlpool Corporation, Cassinetta di Biandronno (VA), Italy
The heat and mass transfer processes occurring in a domestic oven is in detailed analyzed in this work, with the final objective of improving the global energy efficiency of the system. A 3D Finite Element model developed with a Multi-physics approach is validated with the experimental data from the standard test for energy consumption of the European Union (EN 50304:2001). In this test a brick ...
E. Levine, G. Nagashima, D. Hoogerheide, M. Burns, J. Golovchenko
Harvard University, Cambridge, MA, USA
Rowland Institute at Harvard University, Cambridge, MA, USA
Extreme localized superheating and homogeneous vapor bubble nucleation have recently been demonstrated in a single nanopore in thin, solid state membranes . Aqueous electrolytic solution present within the pore is superheated to well above its boiling point by Joule heating from ionic current driven through the pore. Continued heating of the metastable liquid can eventually lead to explosive ...
T. Gulati, A. K. Datta
Department of Biological & Environmental Engineering, Cornell University, Ithaca, NY, USA
Puffing of biomaterials involves mass, momentum and energy transport along with large volumetric expansion of the material. Development of physics-based models that can describe heat and moisture transport, rapid evaporation and large deformations can help understand the puffing process. In this context, a fundamentals based study of salt-assisted puffing of rice is described. A multiphase model ...
N. Baccichet, G. Savini
Department of Physics and Astronomy, University College London, London, UK
Multiphysics Simulation of Polymer-Based Filters for Sub-Millimeter Space Optics This work focuses its analysis on polymer-based filters used in space-borne astronomical instrumentation for Cosmic Microwave Background Radiation and Far-Infrared observations. Most of these observatories mount quasi-optical elements made of such materials, due to their high transparency and low absorption in ...
COMSOL Multiphysics® Simulation of Energy Conversion and Storage Concepts Based on Oxide Crystals - new
C. Cherkouk, M. Zschornak, J. Hanzig, M. Nentwich, F. Meutzner, M. Urena, T. Leisegang, D. C. Meyer
Institute of Experimental Physics, Technische Universität Bergakademie, Freiberg, Germany
Fraunhofer-Technologiezentrum, Freiberg, Germany
A mathematical model based on a finite element method (FEM) is presented as an initial approach for a system converting waste heat energy into chemical energy. This system consists of a pyroelectric LiNbO3 plate placed into a cylinder which undergoes a laminar water flow with an appropriate periodic heat source. It solves the heat transfer equation in non-isothermal flow, where the density of ...
A. Gil-Garcia, I. Kings, B. Al-Duri
University of Birmingham, School of Chemical Engineering, Edgbaston, Birmingham, UK
In clean coal technologies, improving energy conversion efficiency is one of the most important directions. Compared to traditional subcritical power plants, pressure-increased supercritical power plants improve the plant energy efficiency from 35% up to 45%. This work presents a study of the thermodynamic behaviour of the water cycle in coal-fired boilers in response to the changes in energy ...
Use of COMSOL to Estimate the Thermal Properties and Kinetic Parameters for the Degradation of Anthocyanins in Grape Pomace
D.K. Mishra, and K.D. Dolan[1,2]
 Department of Biosystems and Agricultural Engineering, Michigan State University
 Department of Food Science and Human Nutrition, Michigan State University
Degradation of components in low-moisture and high-temperature food is difficult to model because of the temperature gradient and long heating time. A method was developed to estimate the thermal properties of grape pomace and the rate constant and activation energy of anthocyanin degredation.