Unconventional characterization of biodiesel from several sources by thermal lens spectroscopy to determine thermal diffusivity: Phenomenological correlation among their physicochemical and rheological properties.

Highlights: [•] TLS permit to attain conductivity and thermal diffusivity of biofuels. [•] Diffusivities and viscosities were correlated to attain oil/ biodiesel Pr numbers. [•] Thermal diffusivity changed as a function of iodine index value. [•] Thermal diffusivity of biofuels is important to modeling combustion problems. [•] TLS is unconventional tool to qualify the quality of biodiesel. [ABSTRACT FROM AUTHOR]