Multifractal analysis of biodiesel droplet imprints and estimation of the fractal surface energy of the sprayRuslana Kolodnytska, Vyacheslav Kryzhanivskyy, Pavel Moskvin and Oleksiy GromovyyEur. Phys. J. Appl. Phys., 79 1 (2017) 11101DOI: https://doi.org/10.1051/epjap/2017170020