Powering up solar power plants with math

Power plants that utilize solar thermal energy often make use of parabolic troughs, which concentrate sunlight to maximize power generation. Many researchers hoping to optimize parabolic troughs, however, typically focus on only one aspect of these devices, which does not necessarily show how multiple factors can interact and affect the troughs’ performance.

Wang et al. have developed a numerical method that predicts how the performance of a parabolic trough can be influenced by heat, stress and geometry. Using their technique, the authors showed that geometry can affect the way that heat is distributed along a parabolic trough, which in turn changes its stress distribution.

Notably, the authors confirmed that uneven temperature distributions along a trough lead to areas of high stress concentrations. These “stress concentrators,” which in the modeled device became pronounced when its rim angle was 75 degrees, are dangerous for the trough as they can cause them to break, but can be mitigated by optimizing the geometry of the device. This can be done by tweaking the ratio of the trough’s aperture relative to its receiver, as well as its rim angle.

The authors plan to further develop their method so that it considers even more factors – such as different direct normal irradiance levels, transfer fluid mass flow rates, and transfer fluid inlet temperatures – and to compare their results with experiments to verify their method’s applicability to troughs in the real world.

Source: “Optical, thermal, and structural performance analyses of a parabolic-trough solar collector,” by Chunwei Wang, Yanwei Hu, and Yurong He, Journal of Renewable and Sustainable Energy (2020). The article can be accessed at https://doi.org/10.1063/5.0012611 .