Pathway to non-intrusive in-flight flow diagnostics with filtered Rayleigh scattering

Abstract

A pathway to in-flight application of Filtered Rayleigh Scattering (FRS) is herein presented, including a viable concept, based on recently published related work. The proposed pathway considers the key technical, operational and regulatory challenges to enable in-flight measurements using FRS for inlet flow distortion characterisation ahead of the aero-engine. Solutions to these challenges are proposed, in particular methods for light delivery, flow imaging and integration of the measurement system in the in-flight environment. This complements the experimental lab-scale demonstration of a FRS concept for flow distortion measurements and provide a route for further exploitation as a diagnostic tool for the next aircraft generations.