In the spirit of giving away ideas that might make a difference, I’ve written this post to bang on about an idea I had years ago.
I’ve searched the internet over the last few days and I haven’t found anyone else who’s had the same idea. Either that means it’s a bad concept that won’t work or – and I do hope this is the case – it is genuinely new.
The problem with wind turbines, as far as I understand, is that they are less efficient in urban areas and other areas where there is turbulence. I propose that surrounding a horizontal axis wind turbine (HAWT) with vertical vanes that reduce the turbulence will help increase the turbine’s power output. The vanes would have to swivel about their vertical axes to keep their leading edges facing into the wind, i.e. each vane would swivel about its vertical axis at the same time as the turbine swivels to face into the wind.
Furthermore, the angles of the vertical vanes could be angled to “funnel” air to the turbine. This would exploit Bernoulli’s principle and cause the narrowed stream of air to flow faster, increasing its kinetic energy, and thus cause the turbine to spin at a higher rate.
Before I begin, I’d like to point out that I’m not an engineer. My knowledge of aerodynamics is rather on the empirical side and comes from building and flying model planes. If my big idea turns out to be as useful as nuclear-bomb-proof paint then please let me know in the comments.
When I first dreamt this up I thought I’d build a scale model to test the idea. Years went by and I never got around to it so, hopefully, someone else will pick up the idea and run with it.
Bearing in mind I haven’t done any testing, I reckon that two or three rings of vanes would do the trick.
Below are a couple of diagrams showing plan views of what I mean. They aren’t to scale and the angles of the vanes have been eyeballed, not calculated but I hope they give an indication of what I mean.
The first diagram shows the wind blowing from the north. Each circle of vanes is adjusted to channel more air towards the turbine blades.
A second row of turbines at the rear of the outside circle of vanes could possibly exploit the fastest region of moving air. On the other hand this might make the whole setup too complicated.
In the next diagram the wind direction has shifted to the north-east. The vanes are automatically adjusted to accomodate the new wind direction.
Here’s a side view showing a cross-section through the centre of the arrangement. I reckon the vertical vanes need to be slightly taller than the height of the turbine to avoid the tip vortices from the vanes interfering with the turbine blades.
In strong winds the vanes could all be straightened (i.e. all are set at the same angle as the wind direction) to reduce the stress on the turbine blades. I imagine the vane angles would be controlled by the same system that controls the feathering of the turbine blades in current setups.
Let me know in the comments if you think this would work. Assuming someone else hasn’t already patented this, anyone is welcome to use this idea, develop it further and even take it to market. All I ask for is acknowledgement – including a link to my website.