Investigation of pH and SDBS on enhancement of thermal conductivity in nanofluids

The heat transfer enhancement of two water-based nanofluids was investigated under different pH values and different sodium dodecylbenzene sulfonate (SDBS) dispersant concentrations. We found that the stability of nanofluids has a good corresponding relation with thermal conductivity, the better dispersion stability behavior and the higher thermal conductivity of the nanofluids, an optimal pH value and optimal SDBS concentration can result in the highest thermal conductivity of the nanofluids. Therefore, the combined treatment with both the pH and chemical surfactant concentration was recommended to improve the heat transfer enhancement for practical applications of nanofluid.