Conceptual Configuration of Non-Constant Sweep UCAV Concept

Abstract

The design of unmanned combat aerial vehicles (UCAVs) used for military applications is dictated by their low-observability characteristics rather than the aerodynamic performance. Owing to this reason, the UCAVs experience flow separation during takeoff and landing and exhibit stability issues. Moreover, the wing design significantly influences the aerodynamic performance of the UCAV model. The configurations of UCAV models are still under exploration, and the conceptual design of UCAV is still undergoing various developments, so the dimensions and shape of the UCAV design have not been defined yet. Hence, the assessment of the conceptual configurations and their design are worthy issues that need to be investigated. In the present work, the initial weight, aerodynamic sizing, planform selection and then the conceptual design of a non-constant leading-edge UCAV configuration was performed. Later, the obtained conceptual design was optimized using multi-fidelity surrogate models with a vortex-lattice method to achieve a better lift and drag ratio. Lastly, the optimized design was validated using the computational fluid dynamic (CFD) model to verify the accuracy of the surrogate model. It was found that the optimized design exhibited superior lift and drag characteristics compared to the reference design.