simulation des effets thermiques et hydromecaniques d’une turbine installee dans une cheminee solaire.

Abstract

The objective of this workis to simulate numerically the main thermal and hydrodynamic phenomena in a solar chimney with particular attention to the turbine. This study was conducted using ANSYS FLUENT and FLUENT software to simulate the two-dimensional and three-dimensional models of a solar chimney power plant system, with and without a turbine. The simulation was performed for the geometry of prototype of Manzanares, Spain. Our numerical results are compared and validated with experimental and numerical work published. First, a numerical study of a solar chimney is conducted in order to highlight the characteristics of the system and to define the region where the speed of the flow canturn a turbine. We examined the effect air velocity at the collector inlet, and ambient temperature on the system. The temperature, velocity and pressure distributions in the system are analyzed. In order to find the best site to install a solar chimney in Algeria, oven areas are Chosen (Adrar, Tamanrasset, Ouargla and Constantine). The electrical power produced annually and monthly by the solar chimney for the four regions is estimated. In a second step, a numerical simulation in 3D of a solar chimney coupled with turbine was under taken. The turbine has been treated in two ways, either by adopting the fan model, or by coupling the solar chimney with a real turbine of four blades. In the first case, the detailed configuration of the turbine is not taken in to account, it has been treated as an infinitely thin disk. The effect of solar radiation and the pressure drop across the turbine on elements such as the temperature difference in the collector, the efficiency of the collector and the power of the system, is studied. In the second case, the influence of the rotation speed of the turbine on the velocity and the temperature of the flow at the exit of the chimney is examined. The electric power output and the efficiency of the turbine were also estimated.