Image-based Aerodynamic Measurement Techniques

Image-based aerodynamic measurement techniques are being developed at Western Michigan University's applied aerodynamics laboratory under a unified theoretical framework to provide integrated three-dimensional, quantitative optical diagnostics of different aspects of complex flows on and around an object (e.g. aircraft model), and gain a deeper and more complete understanding to related physical phenomena.  In particular, the theoretical foundation for unified flow vector field diagnostics is the physics-based optical flow method. 

These image-based techniques include pressure and temperature sensitive paints (PSP and TSP), stereoscopic particle image velocimetry (SPIV), continuous scalar velocimetry (CSV), planar laser induced fluorescence (PLIF) system, optical skin friction meters, high-speed videogrammetric system for kinematical and geometrical measurements.  The unified image-based aerodynamic measurement techniques allow extractions of various physical quantities of aerodynamic flows from flow visualizations, including the fields of surface pressure, surface temperature/heat-flux, skin friction, velocity, species concentration, model deformation, and model attitude.  Figure 1 illustrates the concept of the unified image-based measurements. 

Several topics being studied are briefly described below.

• Pressure and temperature sensitive paints 
• Physics-based optical flow method for extraction of velocity fields from flow visualization images,
• Global skin-friction diagnostics based on surface flow visualizations with luminescent oil, sublimation coating, and temperature and pressure sensitive paints.
• Photogrammetry/videogrammetry for measurements of static and dynamic model deformation and attitudes and optical force measurements.
• Other relevant topics including skin-friction topology, avian wing geometry and kinematics, comparative scaling of fixed and flapping flyers, wing flow control, and oil droplet deposition in turbulent flow.

Force measurement equipment

AEROLAB sting balance