Alexandria Engineering Journal (Dec 2022)
Analytical and numerical modeling and simulation of heat transfer through raffia vinifera bamboo
Abstract
The permanent search for materials that can improve climatic conditions and thermal comfort in buildings remains a major concern for engineers. The choice of material is motivated by its behavior to the thermal stresses. To predict the distribution of temperature within the material requires mathematical models. In this paper, the heat transfer through raffia vinifera bamboo is modeled using the equation of energy conservation. Raffia vinifera bamboo consists of cork and shell and is treated as two layers material. The thermophysical properties of each layer are constant. The equation is solved analytically by the separation of variables method and numerically by the finite difference method. A numerical simulation with CASTEM software is also performed. A constant temperature is imposed at the external surface of the material while the continuity of the temperature and flux are applied at the cork/shell interface. To test the computational results, the thermophysical properties of the two layers were set equal. The analytical solution in this case of single layer was used as the reference result and the computational methods developed in this work were compared. Results demonstrated that the absolute value of the relative error at the center of material decreases abruptly with time and a maximum value less than 8% occurred for all the developed methods in the paper. Results also indicated that at a given time, the relative error increases slowly to a maximum value less than 8% close the surface. These results showed that the methods presented were correct. The case of two layers with different thermophysical properties was second examined and the raffia vinifera bamboo was viewed as heterogeneous material. The temperature profile at a given time decreases from the surface to the center of the material with a peak occurring at the interface cork/shell. At time t=9750.336s, the temperature at the center increases only by 4.75 °C. Thus, the raffia vinifera bamboo can be used as thermal insulation in buildings.
