Yasser Amini

Most of previous researches on enhancing the heat transfer rate in pipes and channels have focused on passive methods. This article introduces near wall active vortex generators (NWAVG) as a strong way to enhance the heat transfer rate from rectangular channels and simultaneously keep friction losses as low as possible. This article considers three different motion patterns for NWAVG at a constant Reynolds number of 1000. Also, the impact of different numbers of vortex generators and different parameters of each motion pattern on the Darcy friction factor, the Nusselt number and the overall hydrothermal efficiency are examined. The results show that the effect of vortex generators on the heat transfer rate increases significantly when they approach the channel wall. Moreover, the results show that the NWAVG can achieve an 185 % increase in the Nusselt number with an overall hydrothermal efficiency of 1.26.