**Abstract**

In today's era demand of fast processing speed and superior performance of electronic devices creates the problem of huge amount of heat generation. About 100 W/cm<sup>2</sup> heat fluxes has been generating from advanced microprocessors of latest electronic devices and heat dissipation limited to 37 W/cm<sup>2</sup> for air cooling. Semi-circular micro-channel heat sink with Phase change materials still needs to be investigated for the cooling of latest electronic devices as combination of large heat transfer area within a small volume of heat sink and large latent heat released from PCM provides huge amount of heat transfer coefficient which is required to be achieved in the present work. Analytical study of micro-channel heat sink has been performed in the present work at a constant power supply of 95 W using PCM slurry at φ = 0.25 and φ = 0.50 for flow rate in the range of 75 ml/min to 300 ml/min. Heat transfer coefficient of slurry and Nu increases with increase in flow rate. At φ = 0.25 higher heat transfer coefficient and Nu has been observed than φ = 0.50 due to high viscous flow at higher concentration of PCM slurry in micro-channels.

**Keywords:** phase change material (PCM), slurry concentration (φ), semi-circular micro-channel, latent heat, flow rate, heat transfer coefficient
