Numerical investigation of thermo-hydraulic transport characteristics in wavy channels: Comparison between raccoon and serpentine channels

Numerical experiments have been performed to investigate the thermo-fluidic transport characteristics for laminar flow through sinusoidal wavy walled channel. The heat transfer and pressure drop characteristics are assessed for two different channels, namely, raccoon and serpentine for different values of amplitude and wavelength of the wall waviness. Our results reveal that the dependence of heat transfer on the geometry of the wall is strongly influenced by the wavelength of the wall waviness. For lower values of wavelength, the rate of heat transfer is almost same for both the channel, while the heat transfer for raccoon channel is always more than that for serpentine channel for higher values of wavelength and the difference appears to be more prominent for larger values of amplitude of wall waviness and Reynolds number. Furthermore, with the deployment of a performance parameter combining the enhancement in heat transfer and corresponding increase in pressure drop, we assess the thermo-hydraulic performance of the two channels. In contrast to the heat transfer characteristics, our results indicate that the performance factor of a serpentine channel is always more than that of a raccoon channel. The results of the present investigation may be considered as a basis for selection of geometry of channel wall for design of compact heat exchangers.