title: A Continuous Liquid-Level Sensor for Fuel Tanks Based on Surface Plasmon Resonance.
abstract: A standard problem in large tanks at oil refineries and petrol stations is that water and fuel usually occupy the same tank. This is undesirable and causes problems such as corrosion in the tanks. Normally, the water level in tanks is unknown, with the problems that this entails. We propose herein a method based on surface plasmon resonance (SPR) to detect in real time the interfaces in a tank which can simultaneously contain water, gasoline (or diesel) and air. The plasmonic sensor is composed of a hemispherical glass prism, a magnesium fluoride layer, and a gold layer. We have optimized the structural parameters of the sensor from the theoretical modeling of the reflectance curve. The sensor detects water-fuel and fuel-air interfaces and measures the level of each liquid in real time. This sensor is recommended for inflammable liquids because inside the tank there are no electrical or electronic signals which could cause explosions. The sensor proposed has a sensitivity of between 1.2 and 3.5 RIU(-1) and a resolution of between 5.7 × 10(-4) and 16.5 × 10(-4) RIU.
authors.affiliation: Department of Optics, Faculty of Science, Edificio Mecenas, Campus Universitario de Fuentenueva, University of Granada, 18071 Granada, Spain. ampmolin@ugr.es.
authors.forename: Antonio M
authors.initials: AM
authors.lastname: Pozo
authors.affiliation: Department of Optics, Faculty of Science, Edificio Mecenas, Campus Universitario de Fuentenueva, University of Granada, 18071 Granada, Spain. fperez@ugr.es.
authors.forename: Francisco
authors.initials: F
authors.lastname: Pérez-Ocón
authors.affiliation: Department of Civil Engineering, University of Granada, 18071 Granada, Spain. ovidio@ugr.es.
authors.forename: Ovidio
authors.initials: O
authors.lastname: Rabaza
keywords: air-fuel-water interfaces; fuel level; fuel tanks; plasmonic sensor; surface plasmon resonance