Resumo

MARROQUIN-DE JESUS, Ángel et al. Analysis of Flow and Heat Transfer in a Flat Solar Collector with Rectangular and Cylindrical Geometry Using CFD. Ing. invest. y tecnol. [online]. 2013, vol.14, n.4, pp.553-561. ISSN 2594-0732.

The present investigation describes the construction and experimentation of two solar energy absorbersusing water as working fluid and its simulation in Computational Fluid Dynamics (CFD). For Absorber A with rectangular cross section and Absorber B with circular cross section, water temperature was calculated using solar radiation and ambient temperature measurements showing increases of up to 62.5°C for both absorbers. The maximum thermosiphonic flow measurement in Absorber A was 70 l/h and 79 l/h in Absorber B. On this basis, finite element method and CFD were used to analyze the difference between both flows, with 45, 50, 55, 60, 65 and 70 l/h as simulation values. With the simulation results the Reynolds numbers were determined, finding that the maximum flow (70 l/h) gives the largest Reynolds number variation: 25 ≤ Re ≤ 115 for Absorber A and 199 ≤ Re ≤ 235 for Absorber B. With a smaller variation in Absorber B, the flow at all ducts turns out to be more uniform, which results in more ducts transferring heat to the working fluid.

Palavras-chave : flow structure; flat solar collectors; simulation cfd; heat transfer; solar radiation.