The effects of ripple amplitude on heat transfer and fluid flow of X-lattice corrugated honeycombs

A previous study showed that the thermal performance of the X-lattice cored corrugated honeycomb (XCCH) is better than that of most other periodic cellular materials (PCMs). To further improve the thermal performance of the XCCH, the effects of different ripple amplitudes (i.e., a = 0.5, 0.7 and 1.0) on the characteristics of the flow and heat transfer are numerically investigated by thorough comparisons. In terms of the flow characteristics, with the increase of ripple amplitude, the vortex interaction in the channel becomes stronger, which results in evident increase of kinetic energy of turbulence at the boundary of vortex and reduction in the turbulent kinetic energy dissipation. As far as the heat transfer is concerned, within the Reynolds number range of 3696–7436, the heat transfer increases with the increase of ripple amplitude. The overall Nusselt number of the XCCH with a = 1.0 is 15.7% higher than that with a = 0.5. Within the corresponding range of pumping power, the thermal performance of the XCCH with a = 1.0 is up to 7% higher than that with a = 0.5 at relatively higher Reynolds numbers.