Thermal Hydraulic Performance in a Solar Air Heater Channel with Multi V-Type Perforated Baffles

Abstract

This article presents heat transfer and fluid flow characteristics in a solar air heater (SAH) channel with multi V-type perforated baffles. The flow passage has an aspect ratio of 10. The relative baffle height, relative pitch, relative baffle hole position, flow attack angle, and baffle open area ratio are 0.6, 8.0, 0.42, 60˝, and 12%, respectively. The Reynolds numbers considered in the study was in the range of 3000-10,000. The re-normalization group (RNG) k-ε turbulence model has been used for numerical analysis, and the optimum relative baffle width has been investigated considering relative baffle widths of 1.0-7.0.The numerical results are in good agreement with the experimental data for the range considered in the study. Multi V-type perforated baffles are shown to have better thermal performance as compared to other baffle shapes in a rectangular passage. The overall thermal hydraulic performance shows the maximum value at the relative baffle width of 5.0.

Effect of the size of graded baffles on the performance of channel heat exchangers

“…These correlations, which are used by for the characterization of fluid-flow and heat transfer in ducts [24], are available in the literature [40]: Figures 2(a) and 2(b) show, respectively, a comparison of Nusselt number and friction factor obtained from the present study with those from eqs. (11) and (12). In these figures, the presented results agree reasonably well within ±2.9% and ±5.5% for both friction factor correlation of Blasius and Nusselt number correlation of Dittus-Boelter, respectively.…”

“…The shape of baffles is a necessary parameter for the generation of vortices [1][2][3]. Therefore, various shapes have been developed, for example, the V-baffle shape [4][5][6][7][8][9], the W-baffle shape [10], the Z-baffle shape [11], multi V-type perforated baffles [12][13][14][15][16][17] and diamond shape proposed by Sripattanapipat and Promvonge [18]. All these shapes permit an enhancement in the heat transfer rates, but with catastrophic Ppressure drops.…”

Aerodynamics and Heat Transfer over Solid-Deflectors in Transverse, Staggered, Corrugated-Upstream and Corrugated-Downstream Patterns

“…A discrete multi V-pattern rib combined with dimple staggered ribs also had better overall thermal performance compared to other rib shapes. Kumar and Kim [7] reported heat transfer and fluid flow characteristics in a solar air heater channel with multi V-type perforated baffles. The flow passage has an aspect ratio of 10.…”

Investigation of the Effect of Duct Height on the Performance of Solar Air Heater With Baffles

“…The results revealed that the broken multiple V-type baffles are thermo-hydraulically superior as compared to the other baffles. Kumar and Kim [10] showed that multi V-type perforated baffles performed better as compared to other shapes baffle in a rectangular duct. Karim and Hawlader [11], investigated flat plate, finned and V-corrugated solar air heaters.…”