Investigation of effective parameters on relative thermal conductivity of SWCNT (15%)-Fe3O4 (85%)/water hybrid ferro-nanofluid and presenting a new correlation with response surface methodology

In this study, the parameters affecting the relative thermal conductivity (RTC) of SWCNT (15%)-Fe3O4 (85%)/Water Hybrid Ferro-Nanofluid (HFNF) are investigated. The contributions of temperature and the solid volume fraction (SVF) are carefully studied and analyzed. The initial increase of TC of produced HFNF relative to water at SVF = 0.03% and T = 30 degrees C is equal to 0.9%, but the maximum amount of RTC is reported to be 32.20%, which is a significant amount. The contribution of each parameter in increasing the RTC is considered in present sutdy. In this study, in addition to the laboratory study the response surface methodology (RSM) is used as mathematical based method to predict the TC behavior of studied HFNF and after that, the MOD and sensitivity of RTC are applied to check the accuracy f predictions. As the result of the RSM a new correlation with R-2 = 0.9941 is also predicted for the studied HFNF and as another result the highest RTC sensitivity is reported at + 1.58%.