D-shaped optical fiber sensors for the oil and gas industry

Abstract

This study addresses the development of sensor devices based on D-shaped optical fibers, applying them as solutions to different problems faced by the oil and gas industry. The processes used in the fabrication and characterization of the devices are presented, as well as the results obtained from the construction of a computational model. A brief discussion on the divergences found between the numerical model and the experimental results is also presented, focusing on the effect of surface roughness of the D-shaped on the device response. Two different optical fiber technologies were used: plastic optical fibers (POF) and single-mode optical fibers (SMF). The particularities related to each type of optical fiber are also described, as well as the operating parameters of each of the devices produced, such as sensitivity and resolution. Various scenarios were explored, such as adulteration of fuels, detection of leaks in pipelines, level control and management of fertilizer use. From the point of view of adulteration, the sensors were used in tests involving the adulteration of diesel with kerosene, ethanol with water and gasoline with ethanol, encompassing a wide spectrum of possibilities, demonstrating the versatility of the sensor. In the context of leak detection, serial sensors spatially located through the use of optical time domain reflectometry were used. The results obtained showed a high sensitivity for detecting materials with a high refractive index, making the solution especially viable for detecting oil leaks in pipelines. Finally, the use of the sensor in fertilizer management was approached from a computational point of view, where the influence of geometric parameters on the response of the devices was also explored. The obtained results showed that sensors based on D-shaped optical fibers have great potential for the proposed applications, although they have been little explored in the literature.