Simulation of refrigerated space with radiation

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2009
Bayer, Özgür
Performance of a refrigerator can be characterized with its ability to maintain a preset low temperature by spending the least amount of electricity. It is important to understand natural convection inside a refrigerator for optimizing its design for performance. Computational Fluid Dynamics (CFD) together with experiments is a very powerful tool for visualizing flow and temperature fields that are essential for understanding a phenomenon that involves both fluid and heat flow. In this aspect, simulations are performed for compartment and total refrigerator models using the package program Fluent which is based on finite volume method. An experimental study is performed to determine the constant wall temperature boundary conditions for the numerical models. Effect of radiation is also investigated by comparing the numerical study of a different full refrigerator model with a similar one in literature. While evaluating the radiation effect, convection boundary condition is selected by defining overall heat transfer coefficient between the ambient room air at a constant temperature and the inner surfaces of the walls. Based on assumptions, related heat transfer analyses are done using compartment and total refrigerator model analyses. Performing CFD simulations of a refrigerator cabinet for visualizing the flow and temperature fields which is the aim of the study is achieved and some observations that can be useful in design optimization are made.

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Citation Formats
Ö. Bayer, “Simulation of refrigerated space with radiation,” Ph.D. - Doctoral Program, Middle East Technical University, 2009.