Investigation of transitional phenomena using time-resolved temperature-sensitive paint

Abstract

This seminar will introduce the temperature-sensitive paint as measurement technique for transition detection in aerodynamic and hydrodynamic experiments, and present examples of its application for the study of transitional phenomena at moderate to high Reynolds numbers. Two generic configurations are examined in this presentation: an elliptic profile and a flat plate. The experiments were performed in a water tunnel and in a cryogenic Ludwieg tube, thus covering chord Reynolds numbers from 2.5*10^5 to 10^7, Mach numbers up to 0.8, and a variety of streamwise pressure gradients. Using time-resolved temperature-sensitive paint, the following transitional phenomena were investigated: turbulent spots, intermittency in the transitional region, unsteadiness in laminar separation bubbles, and turbulent wedges