Numerical analysis of thermal energy storage effects on solar updraft tower performance with natural and forced draught
摘要
The solar updraft tower (SUT) is an innovative approach for generating renewable energy by converting solar energy into electricity. The efficiency of SUT systems is affected by the integration of thermal energy storage (TES) and the use of forced draught systems. This study investigates the performance of two SUT models, such as Model-A (without TES) and Model-B (with TES), under different radiation intensities and forced convection conditions. Numerical simulations were conducted using ANSYS 16 to assess pressure, velocity, and temperature distributions. A realizable k–ε turbulence model that accounts for full buoyancy effects, along with the discrete ordinate method for radiation modeling, was utilized. For Model-A, both natural and forced convection (inlet velocities ranging from 1 to 3 ms−1) were analyzed, with radiation levels varying from 750 to 1150 Wm−2. Results showed that higher radiation increased the absorber plate temperature from 328 to 355 K and air velocity from 2.3 to 2.89 ms−1. Forced convection significantly improved performance, achieving maximum air velocities of 5.07 ms−1 and 14.49 ms−1 at inlet velocities of 1 ms−1 and 3 ms−1, respectively. Model-B simulations examined TES materials, including quartz, sandy gravel, loam, and sand-rock mix, under forced convection, resulting in absorber plate temperatures of 345 K, 346 K, 349 K, and 350 K, respectively. This study demonstrates the influence of TES integration and forced draught systems on the performance of SUTs, highlighting the potential for optimizing renewable energy generation.