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Go to Editorial ManagerIn the present research, a Matlab program with a graphical user interface (GUI) has been established for studying the performance of a solar tower power plant (STPP). The program gives the ability for predicting the performance of STPP for different tower dimensions, ambient operating conditions and locations. The program is based on the solution of a mathematical model derived from the heat and mass balance for the tower components. The GUI program inputs are; tower dimensions, solar radiation, ambient temperature, pressure, wind velocity, turbine efficiency, emissivity and absorptivity for collector and ground and thermal conductivity and thickness for ground. However, the GUI program outputs are; temperature and pressure differences across the collector and tower, velocity in the tower, density of air in collector outlet, mass flowrate of air, efficiency for collector and tower, the overall efficiency and output power of STPP. The effect of the geometrical dimensions of STPP and some climatic variables on the plant performance was also studied. The results show that the output power increases with increasing the collector diameter, chimney diameter and solar radiation by an increasing of 0.282 kW/m, 0.204 kW/m and 0.046 kW/(W/m2) respectively.
Natural convection heat transfer in porous cavity with arc shape wall filled with nanofluid is studied numerically. The right arc shape wall of the cavity is heated at constant temperature (Th) while the left wall is kept cold at constant temperature (Tc), and the other horizontal walls are thermally insulated. The governing equations of the heat transfer and nanofluid flow are solved Flex PDE software. A temperature independent nanofluids properties models are adopted. The investigated parameters are the nanoparticles volume fraction Ø= (0-0.2), Rayleigh number Ra (10-1000) and arc center Ce (1-∞). The results are presented by contour of streamlines, isotherms and the average Nusselt number. The results have showed that the average Nusselt number decreases with increasing Ce and increases with increasing Ra and Ø.