This paper presents an experimental comparative thermal analysis of Multi Walled Carbon Nano Tubes (MWCNT) in rectangular minichannels. 0.01% volume concentration of MWCNT nanoparticles were suspended in water as base fluid to obtain MWCNT-water nanofluid. MWCNT nanoparticles do not readily get mix well with water, hence functionalization of these particles is carried out. Scanning Electron Microscopy (SEM) analysis is done for the functionalized MWCNT nanofluid. For 0.25lpm (liter per minute), 0.5lpm and 0.75lpm flow rates variation in Nusselt number (Nu), Convective heat transfer coefficient (h), friction factor, pressure drop and pumping power for MWCNT-water nanofluid is compared with water. For all the flow rates considered in present investigation, an increase in all the thermal performance parameters is observed. For 0.5lpm flow rate of nanofluid, the % enhancement in Convective heat transfer coefficient and actual heat transfer rate is 15.48 and 91.21 which is maximum compared to other flow rates considered in the present investigation.
MWCNT, water, nanofluid, rectangular minichannels, thermal analysis
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