Session: 09-13-03: Design Analysis and Optimization of Energy Conversion Systems III

Paper Number: 171287

Aerodynamical Redesign of the Vertical Axis Wind Turbine (Vawt) 

The Vertical Axis Wind Turbine (VAWT) is a turbine where the rotor shaft is perpendicular to the wind while the blade mechanism rotates around it so that it can capture wind from all directions. The previous state of this VAWT utilized a wind shield to reduce the negative torque and had NACA 7715 airfoils that would rotate the base around the shaft, generating power out of the motor. It currently stands as, and previously was, an H-Rotor style VAWT, where blades, or airfoils, are attached to the center shaft to stimulate rotation. Our primary goal was to improve its overall aerodynamic and mechanical functionality while also trying to make it more aesthetically pleasing. To accomplish this, there were three main components to reconstruct: the assembly frame, the wind shield, and the airfoils. The electronics were avoided, as those components and its housing structure lie outside of our scope. Addressing the major changes with respect to the previously listed components: the assembly now has eighteen secure mounting points with an insert-controlled angle of attack, the wind shield was replaced with an acrylic sheet construct, the angler component was consolidated, and the airfoils were remanufactured with superior methods. The airfoil contours tested were the NACA 0010, 4412, and 7715. The 3D printed materials were also changed over to Onyx, a light, strong, and business standard material, from acrylonitrile butadiene styrene (ABS) plastic, a common thermoplastic polymer. The previous assembly design was meant to test sets of three, six, and nine airfoils. The issue is that the six-airfoil configuration is not aerodynamically symmetric. This three-fold symmetry would be the only way to have six airfoils be evenly distributed when there are nine maximum slots, however this configuration is not ideal. Extending it to eighteen slots allows for more even distribution and thus more ideal conditions when testing the three, six, and nine airfoil configurations. The wind shield, now as Plexi glass, is more practical and cost effective, visually appealing, and much lighter, providing less strain on the system, while the angler consolidation decreases the total area of the VAWT. The previous airfoils were NACA 7715, which is aerodynamically sound, but not in VAWT applications. Many VAWTs possess more symmetrical airfoil contours, so it was in our best interest to test multiple airfoil designs to verify this recommendation. Per our finite element analysis (FEA) and computational fluid dynamics (CFD) analysis, the material changes allowed for reduced structural strain, angling reliability, finer finishes, and more applicable aerodynamic airfoils. This VAWT is around 105% more efficient than its predecessor.

Presenting Author: Jorge Cortina Central Connecticut State University

Presenting Author Biography: Student of Mechanical Engineering at CCSU.

Authors:

Jorge Cortina Central Connecticut State University
Zachary Marchi-Guasp Central Connecticut State University
Gabriel Stark Central Connecticut State University
Luz Amaya Central Connecticut State University
David Broderick Central Connecticut State University