Our Blade Design
In addition to the simulation, we will also be construction a small scale prototype turbine as a way of experimentally testing the key concepts behind our design. We will be retrofitting the dual turbine from the previous senior design group to fit our design concept. The will involve building new blades, adding an outside casing around the tower, and constructing new solid tiers within the tower to hold the generators.
The blades will be constructed using sheet metal, steel rods, and wooden ribs according to the following specs in table 1.
The models of each blade were built using an online airfoil plotting tool that allows the user to set design parameters including the profile, chord length, thickness, pitch angle, etc… The plotter will then output a 2-D plot of the profile. This plot can then be input into SolidWorks at a given z-distance using the input curve feature. Each blade model consists of a certain number of profiles equivalent to the number of ribs that each blade has. The models for both the down-wind and up-wind blades can be seen in the following figures.
In House Built-in System
For our small scale prototype, we will also be making a few changes to the previous group’s turbine tower. First we will be adding a conical casing to give the turbine tower both better aerodynamic properties, and a more aesthetically pleasing look. The casing will be constructed using four angle iron supports, and 4 steel rings that will serve as both the conical profile and the surfaces to which the outside sheet metal will be attached. Next we will be adding support structures within the tower of the turbine where each generator will be positioned. A section view of the conical casing and tower super structure can be seen in figure below.
The small scale prototype will also contain a fairly complex planetary gearing system that will add the inputs from either turbine rotor to give a single output. This output will be redirected down the tower to the generators using a bevel gear. The gearing will come from the turbine built by the previous senior design group and will be discussed in more detail in the theory of this report. This gearing can be seen in the following figure.
After brainstorming through multiple design concepts, we developed what we believe is the most efficient and reasonable design for a large scale conventional turbine. Through both the simulation and small scale prototype we hope to show that our design concept will drastically increase the amount of power production possible from a conventional turbine, while simultaneously decreasing maintenance costs through an increase in accessibility and safety.
Drive Train Transmission Designs
Vertical Drivetrain Transmissions created using Solidworks 2014