Assessment of biodiesel-diesel blends with an optical fiber grating sensor

This work shows a method based on intrinsic optical fiber sensor for evaluating biodiesel-diesel blends. A long-period grating refractometric sensor was used to detect the biodiesel volumetric concentration in biodiesel-diesel blends. For this, all biodiesel-diesel samples were diluted in cyclohexane in both 1:1 and 1:2 proportions. The following metrological characteristics were obtained: calibration curve, sensibility curve, resolution curve, conformity, repeatability, reproducibility, combined standard uncertainty and expanded uncertainty. The expanded uncertainties obtained for confidence level of 95.45 % were 3.66 % v/v and 5.94% v/v for 1:1 and 1:2 proportions, respectively.