Thermodynamic performance evaluation of an indoor designed solar air heater duct equipped with V-down baffle blocks having racetrack-shaped staggered openings of varying aspect ratio – an experimental study. Issue 6 (3rd May 2023)

• Record Type: Journal Article
• Authors: Pandey, Rajeev; Kumar, Manoj; Saini, J. S.
• Is Part Of: International journal of green energy. Volume 20:Issue 6(2023)
• Page Start: 656
• Page End: 676
• Publication Date: 2023-05-03
• Subjects: V-Baffle block -- staggered racetrack-shaped perforations -- hole aspect ratio -- energy efficiency -- exergy efficiency; Power resources -- Research -- Periodicals; Energy industries -- Periodicals; Energy development -- Periodicals; 333.79
• DOI: 10.1080/15435075.2022.2083916
• Languages: English
• ISSNs: 1543-5075

Abstract

ABSTRACT: 1This paper presents the thermodynamic performance assessment of an indoor-designed solar air heater (SAH) duct with its absorber affixing the racetrack perforated 45 o V-down baffle blocks in staggered holes array. The experimentation work encompasses studying the effect of parameters like – the mass flow rate of air ( m ˙ ) and the hole aspect ratio (w/d) of baffle blocks on the air temperature rise ( Δ T r i s e ), the energy ( η I ), the exergy ( η I I ) and the thermohydraulic ( η e f f ) efficiencies of the duct under turbulent airflow conditions. The open area ratio (Φ), relative roughness height (e/H) and relative roughness pitch (p/e) of the baffle blocks are maintained constant in this study. The result showed drastic improvement in the performance assessing parameters due to 'w/d' affecting the heat transfer and friction characteristics significantly in the duct. Increasing 'w/d' at lower airflow rate results in a uniform downfall of ' Δ T r i s e ', and ' η e f f '. At an increased flow rate, the energy and exergy efficiencies decrease. The exergy destruction and pressure drop show non-monotonous variations with the hole-aspect ratio. The smallest hole aspect ratio (w/d of 1.04) baffle blocks outperform in all assessment segments providing maximum values as 14.86 o C, 96.81%, 17.46% and 93.95%, respectively, for the air temperature rise, the energy, the exergy and the thermohydraulic efficiency.