Embedded Files
Aereomine's key concept was a vertical airfoil arrangement that would allow for a good envelope of operating angles for a static turbine, eliminating the lion's share of mechanical complexity and expense of distributed small wind turbines. The edge of a building presents an interesting environment for a wind energy system if it can cope with some turbulence, which the vertical foils should theoretically help with. What's shown here is more of the latter day prototype work. There were a few conceptual and architectural elements that would have been extremely economical that ended up not working as well as theorized, so we moved to the dual horizontal axis rotor design as pictured.
One of the changes that we were most excited about was the addition of stator elements. This would have added significant internal structure and stiffness, making the necessary hardware and joinery a much easier problemt to solve. Making the system adaptable to different roof structures was one of the main design goals, and reducing the complexity of the base mounting system was a big part of that. Reducing bending moments in all the elements with that additional structure was a tremendous help.
Aeromine had a lot of pilot deployments to different sites globally. There were two in Europe, one in Taiwan, and two in Texas, although one of those was a dedicated test site at Reese Technology center in Lubbock. We spent most of our effort iterating on the units in Texas.
The design saw a good deal of change over the years, going from a vertically oriented modified industrial fan to a horizontal axis exposed rotor. On the latter we used a hub interface that let us vary angle of attack or pitch (these terms are actually pretty muddy in the wind power world) with a set of printed jig blocks to explore the design environment.
While we would have liked to integrate a simple electrical braking resistor setup on the three phases of a permanent magnet generator for shutdown, eventually it became clear that a fail-safe mechanical brake was necessary. The presence of electrical power in a disconnected system wasn't sufficiently safe. We ended up integrating a stock system, anticipating that down the road we could customize a solution with minimal power draw during operation.
One of my roles at Aeromine was facilitating geometry generation for our fluids team. We went through quite a few parameterizations for the system so that they could perform design of experiments (DOE) on a variety of geometries and scenarios in chunk jobs with cloud CFD partners. Generating water tight geometry for CFD in a manner that is robust to a wide envelope of design change is actually a nontrivial problem! We were in the process of implementing a design that would use FRP pultrusions as the primary structure due to its high strength and economy, which is what is shown here.
There was a lot of work on roof structure integration, which is shown here with an older iteration of the aerodynamic system.
I did a lot of analysis of different options over my time at the company, usually starting at reduced order global models for wind loads and modal analysis, then taking those results to get more granular with design of individual parts. We went through a lot of design iterations to optimize for different market conditions, eventually settling on a system that we would transport intact to minimize installation labor costs.
Page updated
Google Sites
Report abuse