Numerical study on optimization of fillet size on the chimney base of solar updraft tower plant for enhanced performance

Abstract

• The effect of fillet near chimney base of SUT plant was studied with a parametric study. • Seven cases with different fillet sizes were modeled and CFD simulations were run. • The estimated output parameters were compared and the optimized case was proposed. • Case 6 with a fillet size of 2.5 m shows a 61% increment in air velocity. • Case 6 showed 97% increment in power and 96.5% on overall efficiency. A numerical study was performed to optimize the size of the fillet at the base of the chimney of a solar updraft tower plant. A parametric study was conducted with seven different fillet size models (cases 1 to 7). Therefore, seven 3D models with different fillet sizes based on the Manzanares prototype were generated and numerical simulations were performed. Realizable k-ε model for turbulence and DO irradiation model for radiation were used. The flow properties such as temperature, pressure and velocity inside the setup of all seven models were estimated. Performance characteristics such as collector efficiency, theoretical and actual turbine powers and overall efficiency were estimated for all cases and compared. The fillet has a 45° inclination such that the height to width ratio of the fillet was unity. The setup with a fillet size of 2.5 m (case 6) showed the optimum results with an increase in velocity of 61% and an improvement of 97% and 96.5% on theoretical power and overall efficiency, respectively, compared with case 1 (no fillet case).