Numerical and Experimental Modeling of a Low‐Cost Square Pyramid Solar Still in Baghdad

ABSTRACT This research presents a comprehensive experimental and numerical investigation of a low‐cost pyramid solar still (PSS) optimized for the climatic conditions of Baghdad. The study evaluates the system's thermal performance and freshwater productivity through a dual approach. A 3D numerical model was developed using SOLIDWORKS to simulate temperature distributions and heat flux, predicting a daily distillate output of approximately 2.2 L/m². Validation was conducted via a physical prototype tested under real‐world meteorological conditions, including varying solar radiation and ambient temperatures. The experimental results closely mirrored the simulation, achieving a daily yield of 2.1 L/m² and a peak thermal efficiency of 60%. A key finding of this study is the identified “thermal inertia”—the temporal lag between peak solar irradiance and maximum distillate production. The high correlation between simulated and experimental data confirms the reliability of the developed model as a robust design tool. Ultimately, this work demonstrates that the proposed solar still is a technically viable, cost‐effective, and easily manufacturable solution for small‐scale potable water production in arid, sun‐rich regions.