Heat and mass transfer problem and some applications

Kılıç, İlker
Numerical solutions of mathematical modelizations of heat and mass transfer in cubical and cylindrical reactors of solar adsorption refrigeration systems are studied. For the resolution of the equations describing the coupling between heat and mass transfer, Bubnov-Galerkin method is used. An exact solution for time dependent heat transfer in cylindrical multilayered annulus is presented. Separation of variables method has been used to investigate the temperature behavior. An analytical double series relation is proposed as a solution for the temperature distribution, and Fourier coefficients in each layer are obtained by solving some set of equations related to thermal boundary conditions at inside and outside of the cylinder.


Fabrication of nanostructured samples for the investigation of near field radiation transfer
Artvin, Zafer; Okutucu Özyurt, Hanife Tuba; Mengüç, M. Pınar; Department of Micro and Nanotechnology (2012)
Radiative heat transfer in nanostructures with sub-wavelength dimensions can exceed that predicted by Planck's blackbody distribution. This increased effect is due to the tunneling of infrared radiation between nanogaps, and can allow the eventual development of nano-thermo-photo-voltaic (Nano-TPV) cells for energy generation from low temperature heat sources. Although near field radiation effects have been discussed for many years, experimental verification of these effects is very limited so far. In this ...
Heat Transfer Simulation of Rarefied Laminar Flow past a Circular Cylinder
Çelenligil, Mehmet Cevdet (2016-07-15)
Direct simulation Monte Carlo calculations are performed to study the heat transfer in laminar, rarefied flows past a circular cylinder. Results are obtained for flows with Knudsen numbers of 0.02 and 0.2; Mach numbers of 0.102 and 0.4, and also several cylinder temperatures are considered. Calculations show that these flows are attached except for the one with a Knudsen number of 0.02 and a Mach number of 0.4 in which separation occurs in the wake of the cylinder. Results are little affected by the changes...
Hydrodynamic ve Thermal Modelling of Circulating Fluidized Bed Solar Receivers
Bilyaz, Serhat; Tarı, İlker (2016-11-17)
The riser tube solar receiver of a circulating fluidized bed solid particle absorption solar thermal energy system was numerically modeled for analyzing hydrodynamic and heat transfer behaviors of the solid particles in the riser. Hydrodynamics of the model is validated by comparing radial distribution of void fractions with an experimental study. For the heat transfer from the opaque walls of the receiver that is heated to high temperatures by the solar rays concentrated by the heliostat field, a simple fr...
Heat transfer enhancement in water-feldspar upflows through vertical annuli
Ozbelge, TA; Koker, SH (1996-01-01)
Although there are many industrial applications of liquid-solid flows in technology, the available knowledge of heat transfer to or from such flows is limited. In this study the effects of parameters on the enhancement of heat transfer from water-feldspar slurries flowing turbulently upwards in vertical annuli were investigated and the experimental conditions beneficial to the enhancement of heat transfer were determined. It was found that the heat transfer enhancement in upflow of slurries through a vertic...
Detailed simulations of parabolic trough collector for investigating enhancement of heat transfer to absorber tube flow
Uygur, Sinan; Tarı, İlker; Department of Mechanical Engineering (2021-2-12)
In this thesis, a detailed method to simulate heat transfer and fluid flow of parabolic trough solar collectors is presented. An optical model of the considered collector is created with Tonatiuh ray tracing program. The data of ray tracing analysis is exported to MATLAB as a binary file for post-processing. Curve fitting and surface fitting to the data are performed to obtain the heat flux distribution on the absorber tube’s outer surface. User-defined functions (UDFs) for ANSYS Fluent Computational Fluid ...
Citation Formats
İ. Kılıç, “Heat and mass transfer problem and some applications,” Ph.D. - Doctoral Program, Middle East Technical University, 2012.