Experimental analysis on exergy studies of flow through a minichannel using Tio2/Water nanofluids

The present study involves an experimental investigation on rectangular minichannel heat sink for processor cooling of a workstation. The thermal dissipation power of the corresponding system is 25 W. The heat sink is directly in contact to the processor core and subjected to continuous increase in heat flux to the sink depending on the system loading. Water and TiO2 nanofluid with volume fraction of 0.10%, 0.15%, 0.21% and 0.25% is used as the cooling fluid in the experiments with different volume flow rates with a pulsating pump in the range of 210-400 ml/min respectively. The observations were performed with the sink in both horizontal and vertical position in which heat sink is allowed to reach two different temperature limits of 40 °C and 55 °C above which it is subjected to cooling. The Increase in minichannel efficiency was noticed when flowrate increased from 210 ml/min to 280 ml/min with an increment of 53%, but it started to reduce when flow rate approaches 360 ml/min. The outlet exergy and pumping power increases as the flow rate increases to a limit. Furthermore, decrease in efficiency was noticed beyond flow rate of 360 ml/min and the highest outlet exergy was found at a flow rate of 360 ml/min for about 147.52 W. Additionally, exergy analysis is performed for pure fluid under different flow conditions were examined. Further the effect of nanofluid on pressure drop subjected to pulsating flow for varying volume concentrations is also presented.