Assessment of the Turbine Location for Optimum Performance of the Solar Vortex Engine as a Replacement to the Tall Chimney Solar Updraft Power Plant Design

The solar vortex engine (SVE) aims to replace the tall and expensive chimney structure in solar updraft power plants by a shorter less expensive structure named the vortex generator. In this study, the entire SVE system is simulated by CFD to determine the appropriate location for the turbine unit as well as prove the capability of the vortex generator in replacing the chimney. Three different cases for the SVE are considered and compared to corresponding cases of the solar chimney power plant (SCPP). Results revealed that the optimum turbine location is at the outlet hole of the vortex generator. An updraft air velocity of 1.82 m/s was achieved at the outlet hole, compared to 1.56 m/s at the base of a solar chimney with the same diameter as the upper hole. The consideration of the turbine pressure drop did not affect the formation and preservation of the air vortex. So, the 1 m high vortex generator successfully replaced the 8.6 m chimney component in solar updraft power plants, greatly reducing the cost and construction complexity of the plant. The vortex generator accelerated the air delivered from the solar collector, increasing its velocity by 14 times. The SVE's power output is directly proportional to the static pressure drop across the turbine. The mean difference values along the air vortex field between the cases with and without a turbine are 0.67 Pa and 0.026 m/s for the static pressure drop and velocity magnitude, respectively.