Perpustakaan Digital ITB

This thesis discuss about the development of an optimisation framework for preliminary design of HALE-ITB UAV closed-wing design. Simplification of the design is applied by isolating the wing from its body and represent it as two individual wings with gaps and laps. The main objectives of this optimisation are devided into 2 categories. The first one is 2D aerodynamic aspect which uses high fidelity method, and the second one is 3D aerodynamic and structural aspect which uses a low fidelity one. In 2D perspective, the objective is to maximise the aerodynamic efficiency of the wing’s airfoil with respect to its shape and configuration (12 total design variables). While in 3D aspect, the objectives are to develop the wing planform so that it maximise the aircraft flight endurance and structurally efficient (10 total design variables). The optimisation is conducted for several cases within a given aerodynamic, performance, stability, and structural constraints which are addressed to the HALE-ITB UAV requirements. RANSbased CFD is used as high fidelity solver for airfoil analysis, while combination of Datcom, Vortex-Lattice (VLM), and analytical structural method are used for low fidelity analysis in 3D aspects. Ordinary Kriging (OK) is used to assist the optimisation algorithm as the surrogate model of the high fidelity data. NSGA-II is chosen as the optimisation algorithm to find the pareto-front of each case. In result, the optimisation goals are achieved with no conflict of interest found.