Heat transfer operations in microchannel are of special relevance in designing micro-devices involving accumulation of high heat flux. The current study explores simultaneously developing, unsteady laminar flow inside a twisted sinusoidal wavy microchannel and heat transfer involved. A square cross-sectioned channel is taken for the study. The channel is wavy in nature as well as twisted about the flow axis. The modified geometry helps in enhancing out of plane mixing of the fluid and formation of recirculation inside the flow. The evaluation is performed for a Reynolds number range of 1–100. A sinusoidal (varying with time) normal velocity component is employed at the inlet. The study was conducted over a range of pulsation amplitude and frequency. To solve the governing equations, a finite volume based method was employed. The Nusselt number data shows significant enhancement for the sinusoidal inlet velocity as compared to that of a steady case. In terms of pressure drop, the proposed design shows that at different frequencies and amplitudes, it can keep the pressure drop within admissible limits. Entropy generation is used as the measure of dissipated energy. Performance in terms of entropy generation is also reported.
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