Visualization of In-Flight Flow Phenomena Using Infrared Thermography

Abstract

Infrared thermography was used to obtain data on the state of the boundary layer of a natural laminar flow airfoil in supersonic flight. In addition to the laminar-to-turbulent transition boundary, the infrared camera was able to detect shock waves and present a time dependent view of the flow field. A time dependent heat transfer code was developed to predict temperature distributions on the test subject and any necessary surface treatment. A commercially available infrared camera was adapted for airborne use in this application. Readily available infrared technology has the capability to provide detailed visualization of various flow phenomena in subsonic to hypersonic flight regimes. 1 INTRODUCTION The use of infrared (IR) thermography to visualize certain flow phenomena is not new. Infrared technology has been employed in wind tunnels [1] and in flight at subsonic to hypersonic conditions with both local (that is, when the camera and subject surface are on one aircraft) [2,3,4] a...