Numerical investigation of flow and heat transfer characteristics in smooth, sinusoidal and zigzag-shaped microchannel with and without nanofluid

Flow and heat transfer characteristics in smooth, sinusoidal and zigzag-shaped microchannel with and without nanofluid have been investigated by finite volume method. Effects of amplitude and wave length of sinusoidal and zigzag-shaped microchannel, volume of fraction and Reynolds number on heat transfer, performance evaluation criterion were evaluated. The results show that by increasing volume fraction of Copper oxide nanoparticle, Nusselt numbers are increased. Obtained results show that if only the increase in heat transfer is considered, using sinusoidal microchannels without nanoparticles is more effective method than using of nanoparticles in smooth microchannels. By analyzing the effect of wavelength and amplitude on changes of Nusselt number, it can be found that by decreasing sinusoidal and zigzag-shaped microchannel wavelengths, Nusselt number will increase. Also, we concluded that for selection of the best microchannel, the zigzag shaped one is a more appropriate one as compared to the sinusoidal microchannel.