Proof-of-Concept Study of Distributed Measurements of Coal Dust Concentration

Coal dust formed in mines due to the crushing and transportation of coal can lead to many danger situations: from explosions to respiratory diseases among miners. In this paper, it is proposed to use a distributed fiber sensor based on a coreless fiber (CLF) for the task of measuring coal dust concentration. For this purpose a proof-of-study of the effect of external defects on the scattering value in CLF was performed. The optical frequency-domain reflectometry (OFDR) technology is used as a method for studying the reflected/scattered signal from the CLF sensor. To test the possibility of measuring coal dust, the influence of various external factors placed on the CLF surface was studied: a uniform and non-uniform change in the refractive index; influences creating defects on the surface. The experiments confirmed that any of the considered types of impact on the CLF surface can be detected, localized and quantitative characterizated using the the proposed concept.