Vortex generators (VGs) are the most commonly investigated enhancement methods in the field of improved heat exchangers. Illustration of different sizes of fin-and-tube heat exchangers are shown in the figure above. In this study, the effect of delta winglet VG designs in a fin-and-tube heat exchanger (FTHE) with herringbone fin shape was invesitgated numerically using a coupled open source solver in OpenFOAM. The study showed that VGs not only increase the heat transfer in the herringbone fin but also decrease the pressure drop. The highest and longest investigated VG design is found to perform the best because of its ability to delay the flow detachment from the tube, to feed high kinetic energy flow to the recirculation zone and to create longitudinal vortices in the downstream region from the VG.
The herringbone fin fin with VGs enhances the overall performance by 5.23 % in comparison to the fin without VGs.
Read more about the study here.