Anti-icing Fluid Flow off on a Wing Section During Simulated Taxi and Take-off Run

1 Introduction 1 2 Objectives 3 3 Test Arrangement 4 3.1 Wind tunnel 4 3.2 Wing Section Model 4 4 Data acquisition 6 5 Rheological Properties of the Anti-icing Fluid 7 6 Assessment of Measurement Accuracy 8 7 Measurement Program 9 8 Test results 10 8.1 General Observations of Fluid Flow off process 10 8.2 Formation and propagation of waves on fluid surface 12 8.3 Effect of fluid initial thickness to take-off simulation results 15 8.4 Effect of acceleration time to take-off simulation results 16 8.5 Effect of two-step de-icing treatment to take-off simulation results ... 17 8.6 Taxi simulation results 18 9 Conclusion 19 APPENDIX A. Video Frames and Wind Tunnel Data of Test Runs (separate document) Trafi Publications 1/2013 ABSTRACT Flow off process of a selected Type IV non-Newtonian anti-icing fluid was studied in Aalto University Low Speed Wind Tunnel during winter period 2011-12. Wind tunnel model used was a single element two dimensional fixed attitude wing section with a chord of 1.8 m. Wind tunnel test section is 2 m x 2 m. Conducted tests consisted of take-off simulations with approximately linear acceleration up to 60 m/s (120 kt) speed and taxi simulations with constant speeds up to speed of 15 m/s (30 kt). Results showed that during a high airspeed taxi a detrimental premature flow off is possible. Comparison between one-step and two-step de-icing treatment showed no significant differences in fluid flow off properties. Tests generated some data on anti-icing fluid wave formation and propagation that may be utilized in theoretical research.Flow off process of a selected Type IV non-Newtonian anti-icing fluid was studied in Aalto University Low Speed Wind Tunnel during winter period 2011-12. Wind tunnel model used was a single element two dimensional fixed attitude wing section with a chord of 1.8 m. Wind tunnel test section is 2 m x 2 m. Conducted tests consisted of take-off simulations with approximately linear acceleration up to 60 m/s (120 kt) speed and taxi simulations with constant speeds up to speed of 15 m/s (30 kt). Results showed that during a high airspeed taxi a detrimental premature flow off is possible. Comparison between one-step and two-step de-icing treatment showed no significant differences in fluid flow off properties. Tests generated some data on anti-icing fluid wave formation and propagation that may be utilized in theoretical research. Trafi Publications 1/2013