Papers by Dr. Taha Ahmed Abdullah
International journal of mechanical and production engineering research and development, 2020
The correction method is developed to correct the distribution of pressure coefficient around an ... more The correction method is developed to correct the distribution of pressure coefficient around an airfoil for the aim of the post processing of measurement data from wind tunnel. The measured pressure coefficient is numerically corrected to compensate walls interference effects for wind tunnel test section. The airfoil NACA0012, in this paper, is simulated by segments with linear vortex, which are then mirrored due to the floor and ceiling of the wind tunnel test section using sufficient number of images, to simulate the flow around an airfoil in the test section with walls. The perforated wall is approximated by constant source segments. Flow calculations, both in the free stream and with the presence of tunnel walls, are then performed. The numerically pressure coefficient difference obtained between these two cases should be superimposed to the measured pressure coefficient distribution in the wind tunnel for the same airflow conditions and corresponding points, resulting in the experimental pressure coefficient distribution corrected. With the relative height reduction of the wind tunnel test section, the correction values increase. The verification of lift coefficient corrections in this paper is concentrated, where very good agreements have been obtained comparison with several well-known analytical methods.
AL-Rafdain Engineering Journal (AREJ), 2012
An experimental work of continuous normal suction from the wing upper surface effects on the aero... more An experimental work of continuous normal suction from the wing upper surface effects on the aerodynamic forces is carried out, as well as, the effect of normal suction slot channels location and the mass flow rate sucked strength are involved in this study. The wing model with NACA-0015 has been made to achieve normal suction from the wing upper surface by means of four slot channels. The satisfaction of the suction is done by using vacuum pump. The tests are to be done for incompressible flow over wing with and without a continuous normal suction for three different angle of attack 8, 12 and 16 Deg., and for three different Reynolds numbers 13.6×10 4 , 20.4×10 4 and 24.5×10 4. The results showed that the continuous normal suction can significantly increase the lift to drag force ratio, and this ratio is increasing more as the strength of the suction increases.
Tehnicki vjesnik-Technical Gazette, 2015
Original scientific paper The correction method for pressure coefficient distribution around an a... more Original scientific paper The correction method for pressure coefficient distribution around an airfoil is developed for the purpose of the postprocessing of wind tunnel data, obtained from the model pressure measurements. Pressure coefficient distribution around the airfoil, directly obtained by wind tunnel measurements, is corrected numerically in order to compensate for the interference effects of the wind tunnel test section walls. In this paper, the airfoil NACA0012 is approximated by linear vortex segments, which are then mirrored using sufficient number of images with respect to the ceiling and the floor of the test section, to model the flow pattern around an airfoil in the wind tunnel test section with solid walls. Flow calculations, both with the tunnel wall presence and in the free stream, are then performed. The numerically obtained pressure coefficient difference between these two cases should be superimposed to the pressure coefficient distribution measured in the wind tunnel, for the same nominal airflow parameters and angle of attack, at the corresponding points, resulting in the corrected experimental pressure coefficient distribution. The values of corrections generally increase with the reduction of the wind tunnel test section relative height. The paper is focused on the verification of lift curve slope corrections, where very good agreements have been obtained with several well-known classical correction methods.
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Papers by Dr. Taha Ahmed Abdullah