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The aerodynamic performance of an airfoil provides specific information on wing design of HALE UAV and is considered as eminent for enhancing its flight conditions. In this paper, numerical investigation of a wing is conducted to predict its preliminary aerodynamic quality. A concise comparison of lift and drag curve obtained from numerical analysis conducted in two different programs, will be the scope of this research. Preliminary aerodynamic performance study including 12 different wings were previously performed in Fortran program GLAUERT-trapezoidal wing. From those 12 wings, one wing was selected which has the best aerodynamic performance at an operational altitude of 15000 m. Computational fluid dynamic (CFD) software package, ANSYS Fluent is used for numerical analysis of the selected wing. Two different turbulence models were simulated in this work. Lift and drag coefficients were calculated respectively by varying angle of attacks. Hence, the resulted lift and drag curve generated in GLAUERT were compared with those obtained from ANSYS FLUENT. Additionally, other parameters like flow separation, pressure and velocity contours obtained by different turbulent models were also discussed.

This research paper addresses an novel problem that has not been addressed in detail for many decades. Ice formation on aircraft has procedures and protocols to deal with expected and actual problems. Complex modern aircraft are equipped with a variety of techniques to remove Ice formation on an aircraft, especially the wings. The introduction of Unmanned Aerial Vehicles has added an old problem, that of low speed and the lack of power to overcome losses in lift through ice formation. In this research the different types of Ice formation, how they combine and affect Lift and Drag are also addresses in theory and application. Furthermore, practical design and operational recommendations are made for take-off and landing.

Balash, C., Blake, W., & Sterling, D. (2020). Seeking maximum effectiveness and efficiency for large multi-sail penaeid otter boards. Ocean Engineering, 200, Article 107093. https://doi.org/10.1016/j.oceaneng.2020.107093

Impulsively-started flow about sharp-edged rectangular cylinders has been investigated experimentally. The forces acting on the bodies have been determined, as a function of the relative displacement of the fluid at a subcritical Reynolds number, for various angles of attack. The results have shown that the shedding of the first two or three vortices and the manner in which they are generated have profound effects on all the characteristics of resistance. The results have also shown that the drag force in the transient state is always larger than that in the asymptotic steady state, pointing out the importance of the understanding of impulsively-started flow about bluff bodies. The data presented here are expected to form the basis of future numerical analyses of similar time-dependent flows. At present, accurate analytical and numerical data, for comparison with those presented herein, do not exist, save for the later stages of motion where the behavior of flow becomes nearly identical to that of steady flow., http://archive.org/details/impulsivelystart1094519845, Lieutenant Commander, United States Navy, Approved for public release; distribution is unlimited.