Analysis of Superheater Tubes with Mutual Irradiation as Applied to a Solar Receiver Steam Generator
N. Lemcoff, S. Wyatt
Rensselaer Polytechnic Institute, Hartford, CT, USA
Alstom Power, Windsor, CT, USA
The objective of this paper is to analyze the temperature variations within a superheater tube of a solar receiver steam generator. The tube is heated by concentrated, collimated solar irradiation with major cooling by an internal steam flow. The influence of heat loss by radiation, internal convection, and conduction are considered. Analytical models are obtained for an isolated tube, and the ...
H.A. Akhlaghi Amiri, A.A. Hamouda
University of Stavanger, Stavanger, Rogaland, Norway
This paper addresses one of the major challenges in water-flooded oil reservoirs, which is early water breakthrough due to the presence of high permeable layers in the media. COMSOL Multiphysics is used to model two phase (water and oil) flow in dual-permeability porous medium at micro-scales. The heat transfer module is coupled with the laminar two-phase flow interface, because temperature ...
I.M. Abdel-Motaleb, K. Allen 
Department of Electrical Engineering, Northern Illinois University, DeKalb, IL, USA
The design of a RFID-enabled temperature sensor is described in this paper. In this sensor, a change in temperature causes structural beams to bend, which results in a proportional displacement of the plates of the capacitor. Plates\' displacement results, in turn, in changing the value of its capacitance. The capacitor of the sensor is coupled to the LC resonant network of a passive RFID tag. ...
Micromechanical Design of Novel Thermal Composites for Temperature Dependent Thermal Conductivity - new
R. C. Thiagarajan,
ATOA Scientific Technologies Pvt. Ltd., Bengaluru, Karnataka, India
Materials with an order variable in thermal conductivity as a function of temperature are desirable for thermoelectric heat energy recovery, building thermal insulation and solar thermal applications. Thermal Conductivity is an inherent material property. Engineering the fundamental thermal conductivity needs manipulation at thermal photon level for conventional materials. Engineering thermal ...
C. K. Kuruba , R. C. Thiagarajan ,
 ATOA Scientific Technologies Pvt Ltd, Bangalore, Karnataka, India.
Ventilation is mainly used to control indoor air quality and for the purpose of thermal comfort by diluting and displacing pollutants. Because of the effects it has on health, comfort, and serviceability, indoor air quality in our homes is becoming of increasing concern to many people. Many countries even push citizens to opt for energy conservation , energy savings buildings based on natural ...
Coupled Heat and Moisture Transfer in Building Components - Implementing WUFI® Approaches in COMSOL Multiphysics
B. Nusser, M. Teibinger
Holzforschung Austria, Vienna, Austria
Calculating time-dependent heat and moisture transports trough building components are important tasks in the area of building physics. A well known and worldwide used commercial software for this is WUFI®. From the scientific point of view the restricted access to governing equations is nevertheless a drawback of this software. In the present paper it is shown how the physical approaches used ...
Coupling Heat Transfer in Heat Pipe Arrays with Subsurface Porous Media Flow for Long Time Predictions of Solar Rechargeable Geothermal Systems
P. Oberdorfer, R. Hu, M. Azizur Rahman, E. Holzbecher, M. Sauter, P. Pärisch
Applied Geology, Geoscience Centre, University of Göttingen, Göttingen, Germany
Institute for Solar Energy Research Hameln/Emmerthal (ISFH), Emmerthal, Germany
An increased share of renewable energies is regarded as an integral part of a strategy towards a sustainable future. With regard to the heat supply sector this may be achieved using solar thermal collectors or heat pump systems with borehole heat exchangers. During the last years solar thermal and geothermal systems have generally been installed separately. Now, several proposals are discussed ...
S. Carcangiu, B. Cannas, G. Concu, N. Trulli
Department of Electric and Electronic Engineering, University of Cagliari, Cagliari, Italy
Department of Civil Engineering, Environmental and Architecture, University of Cagliari, Cagliari, Italy
Department of Architecture and Planning, University of Sassari, Alghero, Italy
An experimental program has been developed, with the purpose of evaluating the reliability in building diagnosis and characterization of an integrated analysis of several parameters related to heat transfer process through the building material. The Infrared Thermography Technique (IRT) has been applied. Experimental measurements have been carried out on a concrete structure with an inside ...
S. Pemberton, K. Ekici, R. Arimilli
The University of Tennessee, Knoxville, TN, USA
Perspiration during intense physical activity is an essential part of human thermoregulation. Clothing affects the cooling rate of the body. Heat and water vapor are coupled through evaporation and transported through the fabric. A model of the above system was developed for fabrics of different properties to simulate human cooling using COMSOL Multiphysics®. Equation-based modeling allows the ...
H. Zhu, T. Gulati, A. K. Datta, K. Huang
Institute of Applied Electromagnetics, Sichuan University, Chengdu, China
Department of Biological and Environment Engineering, Cornell University, Ithaca, NY, USA
Microwave drying of fruits and vegetables in a domestic oven has been found to result in large textural changes in the product such as puffing, crack formation and even burning due to the inhomogeneous heating of the microwaves. Microwave drying of potatoes is a complex interplay of mass, momentum and energy transport. Three phases are considered in the system: solid (skeleton), liquid (water) ...