Abstrakt: |
This study aimed to investigate the effect of the cationic chitosan dispersant on the thermal conductivity, dispersion, and the suspension of 15nm Al2O3/water nanofluid. The study employed two-step method to mix the Al2O3 powder, deionized water, and dispersant to conduct an experiment of the settling properties and thermal conductivity of nanofluid in a stable environment, analyzing the adhesion of nanofluid to copper pipe walls in practical operations. The results indicated that 1.0wt.% Al2O3/water nanofluid with 0.05 wt.% cationic chitosan dispersant increased its thermal conductivity up to 4.1% and 12.6% compared with nanofluid with deionized water at the temperature of 15°C and 55°C. At the flow ratio of 2 L/min, the overall heat conductivity improved by 8.3% and 17.4%, respectively, under 60W and 150W heating power. The solution performed better in dispersion and suspension than that in the original sample with no cationic chitosan dispersant. The cationic chitosan dispersant, as a result, was proved to improve the dispersion and suspension of nanofluid. It also helped to reduce the frequency of nanoparticles sticking to the pipe wall, increasing the practicability of nanofluid. [ABSTRACT FROM AUTHOR] |