The aim of this thesis is to create a CFD model of a fluidized bed to study the heat transfer having concentrated solar as a heat source. First, some background about concentrated solar energy, a review of its actual potentials and barriers and a comparison among other energy sources will be exposed. Then the fluidized bed concept and the recent studies about heat transfer will be presented and discussed.
The core of the thesis will be based in creating a CFD model to predict the behavior and understand the interactions in a fluidized bed when is irradiated with concentrated solar. It has been decided to create a 2-D model of a rectangular fluidized bed with solid particles of SiC. First, the model has been tested and validated without the heat source and then the heat source has been added. Once the simple model has shown the desired results it has been upgraded including heat to the model. A crucial part of the study was how to model the heat source and how to implement it into the model. With the data obtained from current studies an approach of the heat source to a Gaussian distribution with its peak in the focal point has been made. Then this heat source has been introduced in the model affecting always the surface of the bed.
Once the heat model has been set up two different cases have been studied: a fixed bed and a fluidized bed. In the fixed bed case, the temperature in the focal point increase very rapidly like in the current studies due to that a high amount of energy is concentrated in a very small region. On the fluidized bed case, the temperature of the bed fluctuates due to the high mixing and interaction that there is in the bed that improves the heat transfer between the solid particles.
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