Large eddy simulation of single-phase forced convection in pillow plate channel with periodic boundary conditions

•The mean flow suggests that the flow is statistically stationary.•Within pillow plate channels, turbulent flow is highly anisotropic.•the spanwise Reynolds stress is higher than the other components of stresses. Most of the literature focused on the mean flow characteristics of pillow plate channels and there is lack of understanding on the turbulent motions inside the pillow plate channels. Hence, in this work, the flow and heat transfer characteristics in a pillow plate channel is investigated using the large eddy simulations (LES). The simulations are performed on a periodic section of the pillow plate channel. The average Nusselt number obtained from the LES model is validated with the experimental value available in the literature. The simulations are carried out for Reynolds number, Re = 7800. Water is considered as the cooling medium for the large eddy simulations. It is observed that the spanwise Reynolds stress is consistently higher than the streamwise and wall normal stresses. This is due to the movement of the recirculation zones within the channel as observed during the analysis of instantaneous flow features. The flow is observed to be moderate to highly anisotropic. It is found that the heat transfer enhancement is mainly due to the high velocity in the primary core flow zone in the pillow plate channel.