Experimental and numerical analysis of the heat transfer in a packed bed exposed to the high thermal radiation flux
Autor: | Mario Toledo, Gustavo Ruiz, Nicolás Ripoll, Vojislav Jovicic, Antonio Delgado, Ana Zbogar-Rasic, Nataliia Fedorova |
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Rok vydání: | 2019 |
Předmět: |
Fluid Flow and Transfer Processes
Packed bed Materials science Mechanical Engineering 02 engineering and technology Mechanics 021001 nanoscience & nanotechnology Condensed Matter Physics Thermal conduction Granular material 01 natural sciences Discrete element method 010305 fluids & plasmas Heat flux Thermal radiation 0103 physical sciences Heat transfer Thermal 0210 nano-technology |
Zdroj: | International Journal of Heat and Mass Transfer. 136:383-392 |
ISSN: | 0017-9310 |
Popis: | This paper investigates temperature profiles and heat fluxes in a packed bed heated by radiation that simulates solar energy flux. For this purpose, the discrete element method (DEM) was used along a heat transfer model (conduction and radiation mechanism). Short-range model is proposed for considering thermal radiation in a discrete elements system, which represents an easy-to-implement and low-computational-cost alternative. As results of the simulations, thermal profiles through the packed bed were obtained, as well as the accompanying heat flux. Experiments were performed in a packed bed of inert ceramic particles (alumina spheres). A radiant porous burner was placed at the bottom of the packed bed to simulate an imposed concentrated solar heat flux. Numerical results show good agreement with experimental data. In addition, the thermal profiles, obtained by the heat transfer model in DEM, were compared with the results obtained by discretizing the conservation of energy equation of the solid phase using finite differences, showing a correlation between the power and temperatures reached. It is concluded that the radiation model proposed provides the basis to continue with the study of granular materials at high temperature, where radiation is the dominant mechanism. |
Databáze: | OpenAIRE |
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