Reducing thermal imbalances and flow nonuniformity in solar collectors through the selection of free flow area ratio

Autor: Juan Manuel Garcia-Guendulain, J.M. Riesco-Ávila, Martín Picón-Núñez
Rok vydání: 2020
Předmět:
Zdroj: Energy. 194:116897
ISSN: 0360-5442
Popis: The effect of the riser to header diameter ratio and total cross-sectional area ratio on the flow distribution and thermal performance of flat-plate solar collectors is investigated. An analytical model based on the mass and momentum conservation equations is developed to determine the pressure drop and flow distribution in flat plate collectors. A numerical model is also developed to the assess the thermal effects of flow maldistribution. The accuracy of both models is verified against comparison with experimental measurements taken from the open literature. The use of the models is then extended to cover the flow distribution in solar collector networks. It is found that for laminar and turbulent conditions, cross-sectional area ratios and diameter ratios equal or lower than 0.75 and 0.25 respectively, minimize flow nonuniformity and reduce thermal imbalances. The results can be used for design purposes.
Databáze: OpenAIRE