Heat Transfer Enhancement inside Rectangular Channel by Means of Vortex Generated by Perforated Concave Rectangular Winglets

Abstract

Passive methods using vortex generators (VGs) to enhance heat transfer have been a concern of researchers in recent decades. This study is intended to investigate the strength of the vortex generated by VGs by trying to reduce the pressure drop in the flow. The present work also takes into account the influence of the vortex intensity on the improvement of heat transfer, which can be indicated by the low value of the synergy angle. Experiments were carried out in the current investigation to validate the results of the numerical simulations in the Reynolds number range of 3102 to 16,132. The study results indicate that the observed heat transfer coefficients from the experimental and simulation results have a similar tendency with relatively small errors. A reduction in pressure drop is observed with the use of perforated concave rectangular winglets (PCRWs) against the nonperforated ones although there was a slight decrease in heat transfer improvements.

Evaluation of Vortex Generators in the Heat Transfer Improvement of Airflow through an In-Line Heated Tube Arrangement

“…Validation was necessary to ensure that the experiments carried out were going in the right direction. This validation was carried out by comparing the current experiment with the experiment from Whitaker, for which validation results can be seen in previous studies [31]. In the validation, the current experimental conditions were adjusted to the experimental conditions used by Whitaker.…”

“…Although the results of their study were not as expected, they showed a significant decrease in pressure drop. In a subsequent study, Syaiful et al (2021) tried to investigate the use of concave rectangular winglet (CRW) VGs for increasing the heat transfer rate, where CRW VGs showed a better thermal improvement than concave delta winglet (CDW) VGs [31]. As with previous studies, they found that pressure drops could be reduced with the use of perforated VGs compared with non-perforated VGs.…”

Numerical Investigation of Heat Transfer Enhancement in Circular Channel with Variation in Angle of Delta-Winglet Vortex Generator

“…The computational domain consists of an upstream extended region, the test region, and an extended downstream region. Before entering the test section, the extended upstream region is used to obtain fully developed flow [21,22]. Subsequently, the air passes through the test section, which contains 56 pairs of the DW VGs arranged on the top and bottom surfaces of the flat plate in an inline configuration.…”

“…The surface of the circular channel is subjected to heat induction along the test section. The air passes through the extended downstream region, which helps prevent reverse flow [21,22]. The schematic of this computational domain is shown in Figure 4.…”

Enhancing Heat Transfer in Rectangular Channels: An Experimental Study on Perforated Concave Delta Winglet Vortex Generators

“…The results showed the heat transfer performance/volume (Qv) and pumping power/volume (Pv) increased by 12.5% and 7.41%, respectively, when using DWP on corrugated FTHE. Furthermore, Siwi et al [15] and Hendraswari et al [16] conducted a numerical analysis of DWP, CDWP, RWP, and CRWP with an angle of 15°. The study showed the concave VG outperformed the flat VG shape due to the generation of more significant vortices.…”