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Micro wind power generation through vertical axis wind turbines for low wind velocity in the department of Santander, Colombia, is viable due to the physical characteristics of the region. However, there are crucial factors for the development of a turbine for the region such as turbine typology, robustness, aspect ratios, etc. For this reason, it is a good practice to perform simulations through computational fluid dynamics (CFD) to predict the performance of the turbine in operation. In this context, an analysis of six configurations of a Darrieus-type VAWT turbine with the asymmetric profile DU06W200 and straight blades, which were obtained by an algorithm considering the factors mentioned above was carried out. The height-diameter ratios to be analyzed were 0.25 (with chord lengths of 0.117 and 0.173 m), 0.4 (with chord lengths of 0.0929 and 0.137 m) and 1 (with chord lengths of 0.0587 and 0.0864 m). It can be concluded that with a ratio of 0.25 and a rope length of 0.173 m, it is possible to obtain an average Power Coefficient of 0.31, which is an outstanding value due to the low wind velocity of the region of interest. [ABSTRACT FROM AUTHOR]

A vehicle is more stable when the geometric center, center of gravity, and stagnation point are in line. However, the inflow direction and velocity magnitude of the operational environment of road vehicles are varying. This study aims to investigate the aerodynamic behavior of a water-drop-shaped vehicle under side wind conditions. Some essential aerodynamic performances of the vehicle are numerically and graphically analyzed at 0 deg, 10 deg, and 20 deg of side wind directions. The value of the coefficient of drag, drag force, coefficient of lift, and lift force exponentially increases as the yaw angle elevates. The lower part on the area of the front-wheel compartment becomes the critical location indicated by the results on pressure coefficient, friction coefficient, and total wall shear stress distribution along the vehicle surface. Increasing the side wind angle triggers more significant vortex regions generated around the wheel compartment and on the leeward side of the vehicle. [ABSTRACT FROM AUTHOR]

This research article presents a design methodology for primary control surfaces (Ailerons, Rudder and Elevator) for experimental unmanned radio-controlled aircraft. The methodology is based on the proposal and standardization of the required mechanical and aerodynamic analysis for each control surface sizing, considering the SAE Aero Design competition objectives within Micro Class. It is used on empirical results previously described in references about aeronautical design, computerized fluids dynamics (CFD) software, and aircraft controllability regulations in order to obtain the design variables. Based on this information, the iteration sequences required for design were automated by a C++ language code to obtain the optimal characteristics for each surface, thereby reducing the possibility of calculation errors, overall time, and workload invested in the design process. The application of the methodology to the latest aircraft design reduced the total control systems weight to the aircraft's empty weight ratio to a minimum of 3.4%. [ABSTRACT FROM AUTHOR]

The use of vertical axis wind turbines (VAWT) in Colombia could tackle the energy distribution difficulties as large parts of the territory are not connected to the electrical grid. The present research experimentally determines the wind resource available of a rural place known as Chicamocha's canyon and selects the airfoil for a VAWT blade through CFD modeling. By using the mean wind speed of the location, the performance of the NACA0018 and DU06W200 airfoils is evaluated in terms of the lift and drag coefficients through a 2D CFD modeling using OpenFOAM and the "Spalart-Allmaras fv3" turbulence model. It is found feasible the use of wind energy at the location where the mean year density power is 485 [W/m²], and the DU06W200 airfoil is suggested for constructing the blades of a VAWT, as its aerodynamic efficiency (cl/cd) overcomes by 14% the commonly used NACA0018. [ABSTRACT FROM AUTHOR]