Design and aerodynamic evaluation of a medium short takeoff and landing tactical transport aircraft

Abstract

The present article deals with the conceptual design of a new medium short takeoff and landing tactical transport aircraft, which is intended to expand the institutional capabilities of the Colombian Air Force in terms of versatility and flexibility. An original design strategy was developed during the conceptual design, combining classical methodologies and high-fidelity computational fluid dynamics (CFD) simulations. This methodology allowed the aircraft to be assessed in a single design space, based on its design requirements, mission, and applicable airworthiness standards. Once obtained a baseline concept, the aerodynamic study focused on the flow around two types of wingtip devices: tip tanks and blended winglets. These devices were designed to optimize the performance capabilities of the aircraft, while keeping simple certification procedures. Wind tunnel experiments and CFD simulations were carried out to evaluate and select the best configuration. Lift, drag, and pitching moment coefficient charts, along with vorticity contours, are presented. Results showed that blended winglets have a significant potential for improving aircraft performance without severe structural weight penalties, allowing additional payload capabilities and/or increased range and fuel savings. Finally, the optimized aircraft is compared to major competitors in order to discuss and highlight its main advantages and feasibility for future production.

Drag reduction of a commercial bus with add-on aerodynamic devices

“…The maximum wind speed is 25 m/s with a maximum intensity of turbulence of about 0.15%. Other studies performed at this wind tunnel can be found in Ribeiro et al, 25 Bravo-Mosquera et al, 34 Mezarina et al, 35 Florez et al, 36 and Bravo-Mosquera et al 37…”

“…The maximum wind speed is 25 m/s with a maximum intensity of turbulence of about 0.15%. Other studies performed at this wind tunnel can be found in Ribeiro et al, 25 Bravo-Mosquera et al, 34 Mezarina et al, 35 Florez et al, 36 and Bravo-Mosquera et al 37 Local temperature and atmospheric pressure were acquired with an ITWH-170 INSTRUTEMP weather station. The drag force was measured with a TE-81 aerodynamic balance (uncertainty of 60.02N), while the dynamic pressure was measured with a Pitot tube connected to a digital micro manometer DP-CALC TSI (uncertainty of 60.1 Pa).…”

“…A uniform velocity profile of 23.8 m/s was set at the inlet to obtain the same Re as the wind tunnel tests. Note that the turbulence intensity of the free stream flow in the wind tunnel test section is about ±0.15% at U ∞ = 25 m / s 34 ; hence, a uniform inflow is likewise imposed at the inlet of the computational domain, allowing for precise measurement of the flow structure surrounding the vehicle model. 46 At the outlet, the boundary condition was set as zero relative average static pressure.…”

Developments in Wingtip Vorticity Mitigation Techniques: A Comprehensive Review

“…The blended winglet proved to be the most beneficial design, with a 22% reduction in drag compared with the plain wing. Bravo-Mosquera et al [78] showed that the blended winglet provides a considerable improvement in aerodynamic efficiency despite a very small increase in the wingspan and wing surface.…”