Experimental study on flow properties of jojoba oil-diesel fuel blends with/without alcohols additives

The flow characteristics of different jojoba oil–diesel fuel blends (JDFBs) with and without additives (diethyl ether or Butanol at 5, 10 or 15 %) were experimentally examined to assess their flow performance in comparison with diesel fuel. The density and kinematic viscosity of jojoba oil, diesel fuel, and their blends were measured using an SVM 3000 Stabinger Viscometer (Anton Paar). Rheograms and viscosity–shear rate profiles were derived using the MCR 92 Modular Compact Rheometer. The density of pure diesel fuel increases slightly upon the addition of jojoba oil. For example, at 40 °C, the density increases from 0.813 g/cm³ for pure diesel to 0.87 g/cm³ for the JDFB with 50 % jojoba oil content. Moreover, the kinematic viscosity increases gradually with jojoba oil content, ranging from 4.06 cSt for pure diesel to 4.76, 9.16, and 20.30 cSt for JDFBs containing 10 %, 25 %, and 50 % jojoba oil at 20 °C, respectively. The power-law model can predict the flow behavior of JDFBs up to 50 % jojoba oil content. The dynamic viscosity increases from 3.60 mPa.s for pure diesel to 4.97, 6.75, and 12.17 mPa.s for JDFBs containing 10 %, 25 %, and 50 % jojoba oil, respectively, at 20 °C. The increase in the viscosity of the blend was managed either by heating and / or adding non-viscous alcohols. At 60 °C, the viscosity reduction reaches approximately 64 % for the JDFB with 50 % jojoba oil content. The viscosity reduction is more notable when using diethyl ether as an additive than when using butanol. For instance, the 15 % of Butanol addition, caused the viscosity of the blend to be very much comparable to the diesel fuel.