Houari Ameur

This work consists of a numerical study of a thermally stressed rotary kiln shell part in a cement plant. The numerical simulations are performed by using the finite volume method for the discretization and the simple algorithm for resolution. The velocity air injection, its temperature, and the kiln rotational velocity are the main parameters under investigation. The distribution of temperature, velocity, and pressure, as well as the evolution of the Nusselt number are determined. In the second step of this study, fins are inserted on the shell to examine their effect on cooling. The results analysis shows that the insertion of fins to the shell has a significant influence on the decrease in temperature of the shell’s external surface. The study shows that this decrease in temperature depends significantly on the air injection rate, not on its temperature, and a bit less on the rotating velocity of the kiln. To avoid overloading our equipment (weight of the shell), only four fins distributed around the kiln are added to explore their effect.

The increase in the heat dissipation rate in heat sinks (HSs), the reduction of the occupied volume and mass, and the elimination of the lower heat transfer areas (LHTAs) behind the pins are the main parameters to be controlled in HSs design. For this purpose, this study is devoted to numerically investigating the effect of the combination between perforation technique and splitters inserts on the heat dissipation and turbulent fluid flow characteristics of pin fins heat sinks (PFHSs). The splitter is located in the back of the pin, and the cylindrical pin fins heat sinks (CPFHSs) are perforated with different pairs of hole numbers. These configurations are named PFHS-0 (without perforation) to PFHS-5. The results obtained for the PFHS-5 show an increase in Nusselt number by 34.91% and a reduction in the thermal resistance by 24.22%, compared with CPFHSs. For the same conditions, the occupied volume and mass of this case are also reduced by 70% and 47.5%, respectively. In addition, the PFHS-5 case ensures the highest hydrothermal performance factor (HTPF) of 1.42 at Re = 8,740.

Although thermoelectric technology is little-known in the public domain, it presents an exciting alternative solution in many cases where lost heat energy can be quickly recovered to produce electricity. In the present paper, an attempt is undertaken to exploit this energy. For this purpose, an experimental study is conducted to produce electricity with the thermoelectric effect by utilizing a device placed on a parabolic concentrator. The device is placed on a solar tracker. The results obtained for two days of two distinct months, January and June, revealed that the production in June was higher than that in January by around 92.86%. This distinction is due to the concentrated solar beam being different on a day in each month. A vital product was recorded by utilizing the concentrator. This gadget permitted us to take advantage of the limit of sun-based radiation to produce power. The power may be stored with a legitimate stockpiling procedure.