Distributed Fiber Optic Temperature Sensing for Bleed Air Leak Detection

ABSTRACT: Luna proposes to design, build, and test a novel leak detection system for the bleed air lines found on advanced tactical aircraft. The proposed leak detection system is based on Luna"s distributed sensing technology, and is capable of detecting and precisely localizing leaks and other temperature events that occur along in the bleed air lines. More than just an alarm system, the proposed technology will provide distributed temperature measurements throughout the aircraft during flight and on the ground, enabling the Air Force to build profiles of expected temperature during typical missions, and look for deviations that may indicate a failure is about to occur. In portions of the aircraft where the temperature is often elevated during flight, Luna"s sensing system will provide data that can be used to eliminate false positive alarms while also assessing temperature-related degradation to critical components housed within those compartments, extending the time needed between servicing or replacement. When a leak occurs, Luna"s leak detection system will provide information on the location, magnitude, and duration of the leak, information that is vital during damage assessment. BENEFIT: Air Force Applications: Luna anticipates that the technology developed during this SBIR will be directly applicable for detection of leaks in bleed air lines on board aircraft, not just the F35. In addition, robust, high resolution distributed temperature sensing will find a range of applications on board aircraft, from monitoring the temperature in the cargo bay to maintaining desired temperature levels near critical instruments. In addition, the miniaturization and ruggedization that will occur as part of this effort will advance Luna"s distributed sensing technology, both temperature sensing and strain sensing, bringing distributed fiber optic structural health monitoring to the Air Force. Commercial Applications: Most commercial and private aircraft have bleed air lines as well. As they strive for more fuel efficiency and longer flights, Luna"s leak detection system will allow their technology to push the design envelope forward. In addition, distributed temperature sensing has applications in industrial chemical processing, nuclear industries, thermodynamics testing, and model verification.