A viscosity model was proposed for oxygenated fuel components; it was based on Eyring’s absolute rate theory and a cubic equation of state Soave-Redlich-Kwong. The viscosity was associated with flow energy which could be divided into the activation energy and the vacancy-formation energy, and then a reference state for simplifying the calculation process was introduced in the present model. This work also reported a viscosity database at temperatures from 243.15 K to 413.15 K and pressures up to 200 MPa for 31 oxygenated fuel components containing alcohols, esters and ethers in order to verify the proposed model. The average absolute relative deviations between calculated and experimental data were lower than 2.37%. Furthermore, the free-volume model, which has a similar consideration of flow energy with this work, was chosen to further investigate the performance of the present model, and in general, the present model showed a better accuracy than the free-volume model. Finally, it was shown that the proposed model could be extended to the mixtures successfully.
Bibliographical noteThe authors gratefully acknowledge the supports provided by the National Science Fund for Distinguished Young Scholars of China [No. 51525604], the Foundation for Innovative Research Groups of the National Natural Science Foundation of China [No.51721004], the National Basic Research Program of China [No. 2015CB251502] and 111 Project [No. B16038].
- Eyring's absolute rate theory
- Flow energy
- Oxygenated fuel
- Free-volume model