Different Nonlinear Regression Techniques and Sensitivity Analysis as Tools to Optimize Oil Viscosity Modeling
Dicho Stratiev,
Svetoslav Nenov,
Dimitar Nedanovski,
Ivelina Shishkova,
Rosen Dinkov,
Danail D. Stratiev,
Denis D. Stratiev,
Sotir Sotirov,
Evdokia Sotirova,
Vassia Atanassova,
Krassimir Atanassov,
Dobromir Yordanov,
Nora A. Angelova,
Simeon Ribagin,
Liliana Todorova-Yankova
Affiliations
Dicho Stratiev
LUKOIL Neftohim Burgas, 8104 Burgas, Bulgaria
Svetoslav Nenov
Department of Mathematics, University of Chemical Technology and Metallurgy, Kliment Ohridski 8, 1756 Sofia, Bulgaria
Dimitar Nedanovski
Faculty of Mathematics and Informatics, St. Kliment Ohridski University, 15 Tsar Osvoboditel Blvd, 1504 Sofia, Bulgaria
Ivelina Shishkova
Department of Mathematics, University of Chemical Technology and Metallurgy, Kliment Ohridski 8, 1756 Sofia, Bulgaria
Rosen Dinkov
Department of Mathematics, University of Chemical Technology and Metallurgy, Kliment Ohridski 8, 1756 Sofia, Bulgaria
Danail D. Stratiev
Institute of Biophysics and Biomedical Engineering, Bulgarian Academy of Sciences, Academic Georgi Bonchev 105, 1113 Sofia, Bulgaria
Denis D. Stratiev
Intelligent Systems Laboratory, Department Industrial Technologies and Management, University Prof. Dr. Assen Zlatarov, Professor Yakimov 1, 8010 Burgas, Bulgaria
Sotir Sotirov
Intelligent Systems Laboratory, Department Industrial Technologies and Management, University Prof. Dr. Assen Zlatarov, Professor Yakimov 1, 8010 Burgas, Bulgaria
Evdokia Sotirova
Intelligent Systems Laboratory, Department Industrial Technologies and Management, University Prof. Dr. Assen Zlatarov, Professor Yakimov 1, 8010 Burgas, Bulgaria
Vassia Atanassova
Intelligent Systems Laboratory, Department Industrial Technologies and Management, University Prof. Dr. Assen Zlatarov, Professor Yakimov 1, 8010 Burgas, Bulgaria
Krassimir Atanassov
Institute of Biophysics and Biomedical Engineering, Bulgarian Academy of Sciences, Academic Georgi Bonchev 105, 1113 Sofia, Bulgaria
Dobromir Yordanov
Intelligent Systems Laboratory, Department Industrial Technologies and Management, University Prof. Dr. Assen Zlatarov, Professor Yakimov 1, 8010 Burgas, Bulgaria
Nora A. Angelova
Department of Mathematics, University of Chemical Technology and Metallurgy, Kliment Ohridski 8, 1756 Sofia, Bulgaria
Simeon Ribagin
Intelligent Systems Laboratory, Department Industrial Technologies and Management, University Prof. Dr. Assen Zlatarov, Professor Yakimov 1, 8010 Burgas, Bulgaria
Liliana Todorova-Yankova
Department of Mathematics, University of Chemical Technology and Metallurgy, Kliment Ohridski 8, 1756 Sofia, Bulgaria
Four nonlinear regression techniques were explored to model gas oil viscosity on the base of Walther’s empirical equation. With the initial database of 41 primary and secondary vacuum gas oils, four models were developed with a comparable accuracy of viscosity calculation. The Akaike information criterion and Bayesian information criterion selected the least square relative errors (LSRE) model as the best one. The sensitivity analysis with respect to the given data also revealed that the LSRE model is the most stable one with the lowest values of standard deviations of derivatives. Verification of the gas oil viscosity prediction ability was carried out with another set of 43 gas oils showing remarkably better accuracy with the LSRE model. The LSRE was also found to predict better viscosity for the 43 test gas oils relative to the Aboul Seoud and Moharam model and the Kotzakoulakis and George.
