STRUCTURAL OPTIMIZATION OF JOINED WING KIT CONFIGURATIONS UNDER AERODYNAMIC LOAD

The main purpose of the wing kit integration is to convert conventional munitions into guided munitions. This integration essentially enables munitions to gain standoff attack capability and extend their range. As conventional... [ view full abstract ]

The main purpose of the wing kit integration is to convert conventional munitions into guided munitions. This integration essentially enables munitions to gain standoff attack capability and extend their range. As conventional wing kits are usually composed of two main wings, in the joined wing configurations, on the other hand, the main wings are supported by aft wings. The joined wing concept has been studied by many researchers early 1980’s and some potential advantages of the joined wings over the conventional ones as light weight, high stiffness and aerodynamic efficiency benefits have been highlighted. However, the advantages of joined wings are not invariably outstanding than conventional wings. In order to have superior advantages, the geometric parameters of the joined wing such as sweep, dihedral, taper ratio and location of the joint should be chosen properly.
In this paper, the joined wing configurations were investigated by changing two key parameters, namely; aft wing sweep angle and the location of the joint. The other remaining parameters; the front wing sweep angle, dihedral and taper ratio, were kept constant due to aerodynamic considerations and/or geometric constraints. An optimization design methodology was developed for an iterative design of the joined wing kits utilizing aerodynamic and structural analysis. To determine range of configurations, a statistical approach; design of experiments was used. The joined wing configurations were then trimmed for 1.0 g cruise. The external aerodynamic loads are simulated using Computational Fluid Dynamics (ANSYS ® Fluent). These generated loads are transformed to the static structural analysis in order to optimize structural stiffness (i.e. tip deflection) of the joined wing kit. A response surface statistical analysis is then applied to determine the optimal joined wing configuration.