Asghar, Asad (1992) Experimental investigations of the vortex flow behind a circular cone at high angles of attack. Masters thesis, King Fahd University of Petroleum and Minerals.
The vortex flow which develops on a flying aircraft or missile becomes asymmetric at some large incidence. This asymmetric vortex configuration can give rise to significant undesirable side forces and yawing moments. The vortex-flow asymmetry was experimentally studied on a circular cone in the low-speed wind tunnel of KFUPM, at high angles of attack. Circumferential surface-pressure distributions were measured, at Re = 142,000 from a - 15 deg to 35 deg. Asymmetric pressure distribution due to vortex-flow asymmetry occurs on the lee-side, at a> 17 deg. Resulting in large side force. Inserting a longitudinal fm between the vortices at a = 25 deg and 35 deg appreciably reduces the asymmetry of the vortices and the side force. The angle of attack, a , at which the lee-side vortex system becomes asymmetric was determined, by smoke-flow visualization, as a function of free-stream Reynolds number Re, for Re = 5,000 to 202,000 (based on cone base diameter). The results show a clear dependence of a on Re and on surface conditions.
|Item Type:||Thesis (Masters)|
|Divisions:||College Of Engineering Sciences > Mechanical Engineering Dept|
|Committee Advisor:||Stahl, Wolfgang H.|
|Committee Members:||Hasan, M. A. Zaqir and El-Shaarawi, Maged A. I.|
|Deposited By:||KFUPM ePrints Admin|
|Deposited On:||22 Jun 2008 16:47|
|Last Modified:||25 Apr 2011 09:23|
Repository Staff Only: item control page