Improvement of thermal performance of Ag nano fluid combined with carbon nano-tube

Abstract

The thermal performance of nano fluid containing Ag NPs with different stabilizers was studied in detail. The wall temperature distributions of the heat pipe containing pure water and a small amount of PAN/Ag, PVP/Ag, L-cys/Ag, and OA/Ag were determined, respectively. With the addition of a small amount of Ag NPs in the pure water, the heat pipe wall temperature became lower than that of pipes filled with pure water. The efficiency under the same conditions was ranked as PVP/Ag > L-cys/Ag > PAN/Ag > OA/Ag. After adding a small amount of CNT in the mixture, the effect was enhanced further. As more CNT became dispersed in the working fluid, the opposite effect was observed. Therefore, the optimal amount is 4 mg/L CNT in nano-fluid. Ag nano fluid could form the multi-scaled surface with higher wettability and spreadability. The wettability of nano-fluid was improved with the addition of a small amount of CNT in the mixture. However, the spreadability of the mixture would decrease significantly in the presence of more CNT.

Keywords

nano fluid / Ag / wettability and spreadability / CNT

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