Novel use of CuO nanoparticles additive for improving thermal conductivity of MgO/water and MWCNT/water nanofluids.

Amburi, Prudhvi Krishna; Senthilkumar, G; Nithya, A

The present work aims to emphasize the improvement in thermal conductivity of magnesium oxide (MgO)/water and Multi-walled carbon nanotubes (MWCNT)/water by adding copper oxide (CuO) nanoparticles. The nanofluids were prepared on volume basis by two-step approach. Initially, two different nanofluids such as 1% MgO + 99% water and 1% MWCNT + 99% water were prepared by ultra-sonication, and the thermal conductivity of chosen fluid samples was measured experimentally by KD2 pro instrument. The Nusselt number, Reynolds number, Graetz number and heat transfer coefficient were examined at two different temperatures such as 30 °C and 40 °C. Again 1% CuO nanoparticle was mixed in above samples and two different hybrid nanofluids such as 1% CuO + 1% MgO + 98% water and 1% CuO + 1% MWCNT + 98% water were prepared. The addition of CuO in MgO/water resulted in 11.3% increase in thermal conductivity compared to MgO/water at temperature of 30 °C. Furthermore, 13.3% improvement in thermal conductivity was attained due to the inclusion of CuO in MWCNT/water at 30 °C. Similar trend was depicted at 40 °C such that the thermal conductivity was enhanced by 12.8% and 14.5% in MgO/water and MWCNT/water due to the inclusion of CuO, respectively. In addition, the nanoparticles volume fraction enhanced the nanofluids' thermal conductivity at lower concentration only.

THERMAL conductivity; NANOFLUIDS; COPPER oxide; MULTIWALLED carbon nanotubes; NUSSELT number; HEAT transfer coefficient; MAGNESIUM oxide

Journal of Thermal Analysis & Calorimetry, 2023, Vol 148, Issue 19, p10389

1388-6150

Academic Journal

10.1007/s10973-023-12374-z