Hydrothermal performance of different alumina hybrid nanofluid types in plate heat exchanger Experimental study

To enhance the energetic and exergetic performances of the counter-flow plate heat exchanger with corrugations, several experiments were conducted using different Al2O3 hybrid nanofluids as a coolant. The combinations studied were Al2O3-SiC, Al2O3-AlN, Al2O3-MgO, Al2O3-CuO and Al2O3-MWCNT in 4:1 nanoparticle volume ratio and 100% Al2O3 with 0.1 vol% concentration suspended in DI water. Parameters which were varied are the coolant flow rate ranging from 2.0 to 4.0 lpm and coolant inlet temperature from 10 to 25 degrees C. Effect of coolant flow rates and inlet temperatures on different parameters like heat transfer coefficient ratio, heat transfer coefficient to pressure drop ratio, pump work, performance index and irreversibility has been investigated. A maximum enhancement of around 31.2% has been observed in the heat transfer coefficient for Al2O3-MWCNT (4:1) hybrid nanofluid with the negligible enhancement of 0.08% in the pump work and 12.46% enhancement in the performance index. The maximum enhancement in the irreversibility is around 1.6% for Al2O3-CuO (4:1) hybrid nanofluid. Among the studied nanoparticle combinations, Al2O3-MWCNT (4:1) gives better performance. This study suggests that Al2O3-MWCNT hybrid nanofluid can be a good alternative to enhance thermal performance.