Half Model Testing for Canard of a Hybrid Buoyant Aircraft

Authors: A. U. Haque, W. Asrar, A. A. Omar, E. Sulaeman, J. S. Mohamed Ali

Abstract:

Due to the interference effects, the intrinsic aerodynamic parameters obtained from the individual component testing are always fundamentally different than those obtained for complete model testing. Consideration and limitation for such testing need to be taken into account in any design work related to the component buildup method. In this paper, the scaled model of a straight rectangular canard of a hybrid buoyant aircraft is tested at 50 m/s in IIUM-LSWT (Low Speed Wind Tunnel). Model and its attachment with the balance are kept rigid to have results free from the aeroelastic distortion. Based on the velocity profile of the test section’s floor; the height of the model is kept equal to the corresponding boundary layer displacement. Balance measurements provide valuable but limited information of overall aerodynamic behavior of the model. Zero lift coefficient is obtained at -2.2o and the corresponding drag coefficient was found to be less than that at zero angle of attack. As a part of the validation of low fidelity tool, plot of lift coefficient plot was verified by the experimental data and except the value of zero lift coefficients, the overall trend has under predicted the lift coefficient. Based on this comparative study, a correction factor of 1.36 is proposed for lift curve slope obtained from the panel method.

Keywords: Wind tunnel testing, boundary layer displacement, lift curve slope, canard, aerodynamics.

Digital Object Identifier (DOI): doi.org/10.5281/zenodo.1109053

References:

[1] E. Reshotko and W. S. Saric, “Flow quality issues for large wind tunnels Flow Quality Issues for Large Wind Tunnels,” AIAA Paper (1997): 97- 0225.
[2] D. Kiichemann, “Problems in Wind Tunnel Testing Techniques.” AGARD Report No. 601, 1973
[3] A. U. Haque, W. Asrar, A. A. Omar, E. Sulaeman, and J. S. Mohamed, “Assessment of Engine ’ s Power Budget for Hydrogen Powered Hybrid Buoyant Aircraft,” Journal of Power and Propulsion, 2015 (in press).
[4] A. U. Haque, W. Asrar, A. A. Omar, E. Sulaeman, and M. A. JS, “Conceptual Design and Sizing of a Winged Hybrid Airship,” 21st AIAA Lighter-Than-Air Systems Technology Conference, 16-20 June 2014, Atlanta, GA. Paper No. AIAA–2014–2710.
[5] J. T. Tambahan and S. D. Ehsan, “winglet technology for the modern aircraft In Proceedings of the 3rd BSME-ASME International Conference on Thermal Engineering (Vol. 20, p. 22).
[6] R. Hills, “A Review of measurements on AGARD calibration models,”Agardograph-64, Advisory Group For Aeronautical Research And Development Paris (France), 1961.
[7] N. Gross and M. R. Number, “The ETW wall interference assessment for full and half models, AIAA paper, 769, 2004.
[8] J. F. Marchman, W. J. Devenport, W. H. Mason, and T. Experiments, “Gap Size Effect on Low Reynolds Number Wind Tunnel Experiments. (Doctoral dissertation, Virginia Polytechnic Institute and State University), 1999.
[9] A. Group, F. O. R. Aerospace, and A. A. Report, A Selection of Experimental Test Cases for the Validation of CFD Codes, AGARD AR, 2(303), 1994 .
[10] W. H. Rae, & A. Pope (1984). Low-speed wind tunnel testing. John Wiley.
[11] H. C. Garner, E. W. Rogers, W. E. Acum, & E. C. Maskell, Subsonic wind tunnel wall corrections (Agardograph-109), 1966, Advisory Group For Aerospace Research And Development Neuilly-Sur-Seine (France).
[12] A. Malik, “Suppression of junction flow effects in half model wind tunnel testing.” PhD Thesis, Loughbergh Univerity, UK, 2011
[13] M. R. Soltani, A. Mamaghani, and A. Bakhshalipour, “Half-Model Testing and Sidewall Effects,” 25th International Congress of the Aeronautical Sciences, 3 - 8 September 2006, Hamburg, Germany
[14] S. Kuppa and Marchman III, J. F. End plate gap effects on a half wing model at low Reynolds nUfy, bers. In a Collection of Technical Papers: AIAA 5th Applied Aerodynamics Conference, August 17-19, 1987, Monterey, California, American Institute of Aeronautics and Astronautics.
[15] H. Schlichting and K. Gersten, Schlichting, H., Gersten, K., & Gersten, K., Boundary-layer theory. Springer Science & Business Media, 2000.
[16] A. Deperrois, XFLR5: a tool for the design of airfoils, wings and planes operating at low Reynolds numbers. Software Package.”, 2010
[17] S. G. Hedman, Vortex lattice method for calculation of quasi steady state loadings on thin elastic wings in subsonic flow (No. FFA-105). Aeronautical Research Inst of Sweden Stockholm, 1966.