Iranian Nanotechnology Society International Journal of Nanoscience and Nanotechnology 1735-7004 8 1 2012 03 01 Preparation of CuO/Water Nanofluids Using Polyvinylpyrolidone and a Survey on Its Stability and Thermal Conductivity 27 34 3924 EN M. Sahooli Nano Chemical Eng. Dep., Faculty of Advanced Technologies, Shiraz University, Shiraz, I. R. Iran S. Sabbaghi Nano Chemical Eng. Dep., Faculty of Advanced Technologies, Shiraz University, Shiraz, I. R. Iran M. Shariaty Niassar Transport Phenomena & Nanotech. Lab., Engineering School, University of Tehran, I. R. Iran Journal Article 2012 01 10 In this article CuO/water nanofluid was synthesized by using polyvinylpyrolidone (PVP) as the dispersant.  Thenanofluid stability period and the heat transfer enhancement were determinedby measuring the thermal conductivities. To study the nano-fluid stability, zeta (ζ) potential, and absorbency were measured under different pH values and PVP surfactant concentrations; also thermal conductivity enhancement was measured based on different volume fraction of CuO nanoparticles and temperature. The results showed that the nano-fluid with PVP surfactant has a good stability of about a week in the optimum pH and PVP concentration which are 8 and 0.095,respectively. Furthermore, in the abovementioned concentration of pH and PVP, optimum CuO volume fraction of 6% was obtained, in which, the thermal conductivity enhancement is 17% at 25oC. Finally, with changing temperature at optimum values (for PVP surfactant and CuO nanoparticles), 31% increase in thermal conductivity was obtained at 50oC. https://www.ijnnonline.net/article_3924_943b5fd1ef60d3a4db537af4a4d0c802.pdf