EXPERIMENTAL STUDY OF NATURAL CONVECTION IN A SOLAR CHIMNEY WITH HYPERBOLIC COLLECTOR

The solar tower consisting of the chimney, the turbine, and the collector, initiated by Jorg Schlaich, is an electrical energy production system. This work aims to understand the phenomenon of natural air convection in the device as a function of solar radiation. A prototype designed at the L.E.T.RE laboratory made it possible to experimentally study the behavior of air in the device. To do this, we carried out readings on the solar tower using measuring devices such as the Midi LOGGER, the pyranometer and the hot wire anemometer. They showed that the air temperature changes depending on the amount of sunlight as well as the speed of the fluid entering the chimney. The temperature of the absorber is maximum between 12:30 p.m. to 1 p.m. with values ​​respectively of 87.1°C 88.5°C and 91.3°C for the days of October 8, October 9, and November 9, 2022. However, the temperature of the fluid drops from the collector to the chimney. The results show that the collector efficiency reaches 19.32% on average 34.05% and 33.49% respectively for the days of 08/10/2022, 09/10/2022 and 09/11/2022. The collector is insulated using polystyrene. With improvements the system could meet the needs for ventilation by thermal draft, drying as well as electricity production.