In this article, we propose a study of heat transfer through a flexible pavement, the wearing course of which is composed of bitumen modified with sugar cane fibers (bagasse). The expressions for temperature and heat flux density are obtained from the heat equation established by Fourrier. The influence of extrinsic parameters such as the convective and radiative heat exchange coefficient on pavement deformations are presented in order to quantify the thermal behavior of the bituminous mixture under lighting and shade.
Composite wall consisting of three layers placed from outside to inside in concrete, plaster and plexiglass, is subject to external climatic constraints evolving in frequency dynamic regime. Goal is to maintain indoor environment at lower temperature for thermal comfort in homes or thermal insulation of cold rooms. By means of excitation pulsation, periods of external climatic stresses for which thermal insulation is effective for this wall system are determined.
An n/p/p+ silicon solar cell under monochromatic illumination with short wavelength is studied in steady state. Photogenerated minority carrier’s density in the base is obtained by solving the diffusion equation with boundary conditions at the surfaces of both the junction and the back. The photocurrent density is calculated and represented as function of junction surface recombination velocity for different absorption coefficient values in the short wavelength range. Then at short-circuit current condition given for large junction recombination values, the back-surface recombination expression is derived as silicon absorption coefficient dependent. As a result, compared with the intrinsic recombination velocity, optimum thickness is extracted for given absorption coefficient corresponding to short wavelength illumination and modeled in mathematic relationship.
New expressions of back surface recombination of excess minority carriers in the base of silicon solar are expressed dependent of both, the thickness and the diffusion coefficient which is in relationship with the doping rate.
In this paper, we propose a method for determining the frequency band of study of a kenaf-based material in frequency modulation. The impacts of depth and heat exchange coefficients at the front and rear faces, are highlighted in the dynamic frequency regime.
In this study, we propose an evaluation method of the thermal inertia for two adjoining materials to one another from the heat capacity. The expression of the capacity has been deducted from the thermal-electrical analogy in dynamic frequency regime. The influences of the exciting pulse and depth in the concrete slab and in the tow-plaster on the heat capacity were presented.
In this paper, we propose a study of heat transfer through a roadway. The expression of the temperature and heat flux density are obtained from the resolution of the heat equation and the Fourier law in dynamic frequency regime. The influence of extrinsic parameters such as coefficients of convective and radiative heat exchange and cloud cover are presented.
The Niayes area is an agricultural region where market gardeners use a lot of fertilizers and pesticides. With irrigation, water infiltration can lead with it chemicals that can reach the groundwater that is used for drinking by the population and other domestics activities. The study presented in this paper is to assess the risk of contamination of the groundwater consecutive to the use of chemicals in the Niayes area. To perform this, we used the HYDRUS-1D software to model and visualize the spread of flow concentration of the constituent considered as pollutant from the soil surface to the water table. For pollutants we considered in our simulations, urea and NPK 46% mainly used in the Niayes area. The amounts of fertilizer considered in the simulations are those recommended by the Regional Agriculture Center of Thi
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