Simulation and Validation of Seasonal Soil Temperature Variations Using COMSOL Multiphysics® Software
L. J. Matel ,
 Green Streets Infrastructure LLC, Seattle, WA, USA
The influence of the energy (heat) stored in the earth as a major factor in environmental soil processes is recognized by the soil science community. The heat (energy) supplied by the earth is known to fluctuate with depth below ground surface and time of year, obviously as a function of solar radiation variations through the seasons. The variation of energy available to drive evaporation can ...
J. Acuna and B. Palm
Department of Energy Technology, KTH, Stockholm, Sweden
The most common way to exchange heat with the bedrock in Ground Source Heat Pump (GSHP) applications is circulating a fluid through a U-formed closed loop in vertical boreholes drilled several tenths of meters into the ground. This study presents and compares the results of eight cross sectional U-pipe Borehole Heat Exchanger configurations. Values from recent experimental temperature ...
Heat Loss Evaluation of an Experimental Set-up for Predicting the Initial Stage of the Boiling Curve for Water at low Pressure
K. T. Witte, F. Dammel, L. Schnabel, and P. Stephan
Fraunhofer Institut Solare Energiesysteme - Department of Thermal Systems and Buildings, Freiburg, Germany
Technische Universität Darmstadt - Institute of Technical Thermodynamics, Darmstadt, Germany
In this paper heat losses and gains are assessed for a specific measuring set-up improving the validity of performance data to accurately predict the initial stage of a boiling curve. Simulation focus on achieving results predicting real measuring data of a plain surface structure. Therefore, the relevant components of the measuring set-up have been implemented in a 2-D axisymmetric model ...
A. Krishnamurthy, G. Chen, B. Ulmen, D. Ahern, G. Miley
University of Illinois at Urbana - Champaign, Urbana, IL, USA
The Helicon-Injected Inertial Plasma Electrostatic Rocket (HIIPER) is a two-stage electric propulsion system comprising of a helicon plasma source and an inertial electrostatic confinement (IEC) device for plasma production and acceleration, respectively. Several diagnostics such as a Faraday cup, spherical Langmuir probe, and gridded energy analyzer have been developed for analyzing various ...
J. R. Chase ,
 Alphabet Energy, Hayward, CA, USA
Thermoelectric materials have no theoretical limit to conversion efficiency of heat into electrical power. In order to compete with other forms of power generation and small-scale energy conversion, thermoelectric converters need to maximize their practical usability when integrated with real-world sources of waste heat, and in real-life service environments. This trade-off reduces itself to ...
J. C. Almachi , J. A. Montenegro ,
 Departamento de Formación Básica, Escuela Politécnica Nacional, Quito, Pichincha, Ecuador
The fixed beds have the advantage of large heat transfer area, for they are used in some designs of innovative nuclear reactors as the reactor FBNR. Inside of study of fixed beds is important to define the following parameters: flow minimum and velocity profile of cooling fluid, temperature profile of cooling fluid and the fuel elements.
M. Bianchi Janetti , F. Ochs , L. P. M. Colombo 
 University of Innsbruck, Unit for Energy Efficient Buildings, Innsbruck, Austria
 Dipartimento di Energia, Politecnico di Milano, via Lambruschini 4, 20156 Milan, Italy
A model for coupled heat and mass transfer in porous, capillary-active materials is validated against experimental data obtained by drying calcium silicate specimens. The accuracy of the numerical solution is qualitatively investigated by considering mass conservation for a set of different cases, varying boundary conditions and numerical setup. It is shown that the model is able to reproduce ...
J. B. Sangiri , S. Ghosh , C. Chakraborty
 Indian Institute of Technology Kharagpur, Kharagpur, West Bengal, India
Lithium-ion batteries are most preferable energy storage devices for its higher energy density, flexible form factor and lightweight design than comparable battery technologies. The present simulation work is focused on incorporating contact thermal resistance within a two-dimensional thermal model of Lithium-ion pouch cells. In the present study COMSOL Multiphysics® software has been used to ...
M. de Bonis, and G. Ruocco
DITEC, Universitµa degli studi della Basilicata, Campus Macchia Romana, Potenza, Italy
Heat and mass transfer involved in drying is studied by using COMSOL 3.4. The effect of air temperature on the performance of the drying process applied to fresh food slices is scrutinized. COMSOL’s flexible formulation is exploited by using special drying kinetics for the substrate, and by including a treatment of the dependence of the properties upon the residual moisture content. The model ...
P-O. Johansson, and J. Wollerstrand
Lund University, Lund, Sweden
In a hydronic space heating system the heat output arises from natural convection and radiation from the radiators. In order to increase the heat output, without replacing the radiators with larger ones, or increasing the temperature level, the radiator can be equipped with add-onfan blowers. In the latter case, the heat output from the radiator will increase due to increased convection. This ...