Lectures on Experimental Aerodynamics

Lectures on Experimental Aerodynamics

The lectures attempt to provide an overview of image-based aerodynamics measurement techniques and their applications for students and researchers. The presented materials include the research results obtained by the WMU group and collaborators in other institutions. 

1. Pressure and temperature sensitive paints (PSP and TSP),
2. Physics-based optical flow method for extraction of velocity fields from flow visualization images,
3. Global skin-friction diagnostics based on surface flow visualizations with luminescent oil, sublimation coating, TSP and PSP,
4. Photogrammetry/videogrammetry for measurements of static and dynamic model deformation and attitudes,
5. 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.

Pressure Temperature Sensitive Paints

• Historical remarks on PSP/TSP
• Foundations of PSP/TSP
• Intensity-based measurement and uncertainty analysis based on PSP system modeling
• Lifetime-based measurement and uncertainty
• Photogrammertry and integration with PSP/TSP
• Applications of PSP/TSP
• Conclusions

Full lecture

Fluid Flow and Optical Flow

• Projected motion equation and optical flow equation
• Variational formulation and Euler-Lagrange equations
• Numerical algorithms
• Application to various flow visualizations

Full Lecture

Extraction of Skin Friction Fields from Surface Flow Visualizations as an Inverse Problem

• Global luminescent oil-film (GLOF) visualization
• Surface heat transfer visualization with TSP
• Surface mass transfer visualization with PSP and sublimating coatings in air and dye in water

Full Lecture

Skin Friction Topology in a Region Enclosed by Penetrable Boundaries

• To obtain high-resolution skin friction fields in regions with penetrable boundaries on surface in complex 3D separated flows
• To examine the skin friction topology by application of the Poincare-Bendixson index formula

Full lecture

Global Skin Friction Diagnostics Using Temperature Sensitive Paint

• Skin friction is the most difficult surface quantity to measure in aerodynamics and fluid mechanics
• Global skin friction diagnostic is highly desirable in studies of complex flows

Full Lecture

Global Skin Friction Diagnostics Based on Surface Mass-Transfer Visualizations

• Global luminescent oil-film skin friction meter
• Global skin friction diagnostics based on surface heat-transfer/temperature visualizations

Full lecture

Skin Friction Topology of Wing-Body Junction Flows

• To obtain high-resolution skin friction fields in wing-body junction flows from luminescent oil-film images taken at multiple viewing angles and positions
• To examine the skin friction topology of wing-body junction flows based on the topological rules

Full lecture

Skin Friction Fields on Delta Wings

Skin Friction Fields and Surface Dye Patterns on Delta Wings in Water Flows

Skin Friction Structures Extracted from Surface Pressure Gradient Field

Flow Structures Extracted from Visualization Images: Vector Fields and Topology

Full lecture

Comparison between Optical Flow and Cross-Correlation Methods for Extraction of Velocity Fields from Particle Images

Temperature Sensitive Paint Heat Flux Measurements in Hypersonic Tunnels

Videogrammetric Technique for Aerospace Applications: From Model Attitude and Deformation to Surface Geometry

• Measurement of attitudes and positions of models and control surface
• Measurement of static and dynamic aeroelastic deformation and extracting vibration modes
• Mapping surface qualities onto surface
• Reconstruction of 3D velocity fields

Full lecture

Thin Wing Vibration Control Using Flexible Fins

Effects of Flexible Fin on Low-Frequency Oscillation in Post-Stalled Flows

• Develop a simple passive device to suppress the natural low-frequency oscillation and reduce drag in deep stall
• Explore the physical mechanisms

Full lecture

Avian Wing Geometry and Kinematics

• Recover avian wing geometry from non-contact laser scanning surface measurements
• Extract avian wing kinematics from videos of flying birds
• Give analytical expressions for avian wing geometry and kinematics for computational and experimental studies

Full lecture

Comparative Scaling of Birds and Aircraft

Full Lecture

Fluid Mechanics of Deposition of Micron Liquid Droplets on Wall in Impinging Turbulent Air Jet

• Flow structures and formation of droplet deposition ring patterns
• Droplet collisions induced by small-scale turbulence

Full lecture

Determining Aerodynamic Loads Based on Optical Deformation Measurements

Videogrammetric Determination of Aircraft Position and Attitude for Vision-Based Autonomous Landing

• To study videogrammetric methods for vision-based landing based on natural ground features
• To develop algorithms for virtual reality simulation and real flight control system
• To evaluate the accuracy of videogrammetric methods

Full Lecture

Flight Testing: Measurements and Design

What is Flight Testing?

• Flight testing is the process of gathering information (or data) which will accurately describe the capabilities of a particular type of airplane, and which can be used to accurately predict and optimize the use of all airplanes of that same type in future missions.
• Flight testing of research airplanes constitutes the gathering of data in regions of the flight environment where little past information has been obtained. This information is then used to design future airplanes that can operate safely in this new environment.
• Flight testing is at the end of the aircraft design process and is a unique part of it.

Full Lecture

Image-Based Aerodynamics Measurements - Transfer from Aerospace to Automotive Applications

Full Lecture

Computer Vision and Measurements in Aerospace Applications

Development of Pressure-Sensitive Paint Systems for Low-Speed Flows and Large Wind Tunnels

Full Lecture

Analytical Inverse Heat Inverse Method for Temperature-Sensitive Coating Measurement on a Finite Base