Continuous Fuel Level Sensor Based on Spiral Side-Emitting Optical Fiber

Chengrui Zhao,Junfeng Ge,Lin Ye,Xun Yu

doi:10.1155/2012/267519

Chengrui Zhao, Junfeng Ge + Show 2 more

Open Access

https://doi.org/10.1155/2012/267519

Copy DOI

Abstract

A continuous fuel level sensor using a side-emitting optical fiber is introduced in this paper. This sensor operates on the modulation of the light intensity in fiber, which is caused by the cladding’s acceptance angle change when it is immersed in fuel. The fiber is bent as a spiral shape to increase the sensor’s sensitivity by increasing the attenuation coefficient and fiber’s submerged length compared to liquid level. The attenuation coefficients of fiber with different bent radiuses in the air and water are acquired through experiments. The fiber is designed as a spiral shape with a steadily changing slope, and its response to water level is simulated. The experimental results taken in water and aviation kerosene demonstrate a performance of 0.9 m range and 10 mm resolution.

Highlights

Fuel level measurement is a great challenge in aircraft fuel systems [1]
Experiments are taken in water and aviation kerosene
A novel optical fiber level sensor was proposed, based on a spiral bent side-emitting optical fiber, which is produced by cladding material crystallization

Summary

Introduction

Fuel level measurement is a great challenge in aircraft fuel systems [1]. The most frequently used level sensor for aircraft is the capacitive level sensor for its good sensitivity and maintainability. When the plane takes off from an airport with hot and wet environment, the moisture in the fuel tank will be congealed and mixed in the fuel, error and short circuit will happen to the capacitive sensor For this reason, ultrasonic level sensor was used to replace the capacitive sensor in the planes like B777, F22, and so forth. There are many implementations for optical fiber side leakage: reducing the thickness of fiber cladding [8]; removing several zones of the cladding [9]; using fluorescent impurity-doped fiber [10]; side-polishing the cladding and a portion of core on a curved fiber [11]; using an etched FBG [12], or using a tilted FBG [13] Until now, these sensors have not been commercialized due to low sensitivity [9, 11], limited range [12, 13], expensive cost [8], and complicated manufacturing [8, 12, 13]

Methods

Results

Conclusion