Thermohydraulic Analysis of a Flat-Plane Solar Collector with Fractal Patterns and Allometric Scaling Using CFD

Abstract:

This work presents the numerical analysis of the thermal behavior of a new model of a flat solar collector. The computational model integrates embedded piping configured in a Rhomboid Tessellation Pattern (RTP), with scaling governed by allometric and fractal principles, constrained within a 3 × 3-branched fractal tree structure. The numerical analysis was performed using Computational Fluid Dynamics (CFD) with Autodesk CFD software. The operation of the collector was estimated with water mass flows ranging from 0.01 to 0.06 kg/s, with the water inlet temperature set at 20°C, and analyzed under two simulated solar radiation conditions, 850 and 650 W/m². The studied collector exhibits superior performance compared to traditional collectors. Specifically, it achieves higher fluid temperatures with similar mass flows, even under lower solar radiation conditions. The collector demonstrates thermal performance with efficiencies reaching up to 84.3% for small mass flows. On average, the collector efficiency was 78.1%. The higher thermal efficiency compared to conventional flat plate solar collectors and the reduction in pressure drop by up to 90% compared to traditional collectors make the collector model analyzed in this study a promising option for systems employing solar collectors or collector-evaporators.

• Periodical: Defect and Diffusion Forum (Volume 445)
• Pages: 97-110
• DOI: https://doi.org/10.4028/p-Dq9PMG
• Online since: December 2025
• Authors: René Rodríguez-Rivera*, Ignacio Carvajal-Mariscal, Hilario Terres-Peña, Sandra Chávez-Sánchez, Arturo Lizardi-Ramos, Juan Ramón Morales-Gómez
• Keywords: Computational Fluid Dynamics, Numerical Simulations, Solar Collector, Thermal Analysis

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