I thought I would send everyone a written idea of how I think everything should work before having a meeting which may be difficult to coordinate. This should give you time to consider your areas of expertise and maybe better ways to accomplish the tasks.
First, I think we must divide the unit into two parts – the wind accelerator (Venturi), with the cowling included, and also the turbine with the cowling included. Optimize each separately and do CFD’s to get peak results. Then marry the two together and get the starting point of where it works best. Hopefully, the CFD on them together will turn out great.
The wind accelerator must be sized to increase the cowlings volume by 59% and increase the velocity to about 21 mph.
We know the cowlings swept area is 9 foot and approximately a 13-foot wind accelerator should increase the cowlings volume by 59% (better check my math). I believe Betz Law can be converted to square inches of the surface area (swept area) so there must be 41% open space inside the cowling for the wind to pass through, or else it will bottleneck.
I believe the funnel of the wind accelerator should be about 36 degrees angle so as not to take too much energy out in the diffusion process. Bevel the edges going in the cowling, plus the outer edge of the funnel (Venturi), and size the opening to 41% of the volume so we get the 21-mph velocity. The wind accelerator will be attached to the rear of the cowling by triangular plates at the outside of the cowling and the inside of the funnel at the 12 o’clock, 3 o’clock, 6 o’clock, and 9 o’clock points. The plates must be pointed in the front and back (elongated football shape).
The wind accelerator will be an inside ring (same size as the cowling) and the larger and a wider outer ring with angled plates to join them together (exact same angle), which gives us the same circumference on the front as on the rear, and no low-pressure pocket to deal with on the back side. The rear will give us the compression-expansion effect of a Venturi and slow the wind down from 21 mph to 13 mph to balance the energy from the front and back (conservation of energy).
We will also gain some energy, as the wind usually starts to slow down before it reaches an obstacle, but in this case, the wind accelerator will be drawing the 13 mph wind in at 21 mph.
The total of the cone and the blades must be no more than 59% of the surface area of the cowling with 41% open for the wind to flow through (must consider bevel on the front of the cowling and avoid bottlenecking).
I believe the angle of the front cone (and rear cone) should be about 36 degrees angle or close to it so not to take too much energy out in the diffusion. The cowling must extend a way out in front of the cone to trap the wind inside. Also, have a top extension to prevent rain and snow from getting inside along with drains if it does.
The cowling is in two sections – the front and the rear with a ring of aluminum to join them together in an airtight fit. The turbine wheel’s outer ring turns inside of this gap and is even with the inside of the cowling. A small flange is in the front of the gap and on the rear of the outer ring to guide the wind from entering the gap. Also, a small flange at the edges of the front cone to guide the wind into the blades and away from entering the rear cone. It may be advantageous to make an exit point in the rear cone for any pressure that may find its way there. The problem with this is the wind accelerator may pull air into it.
When the wind is diffused by the front cone it must be guided to make the turn off the blades and in the direction of the rear cone angle. With the angle and twist of the blade, we can make the wind flip a 90 or 180 degrees turn to do this with the help of the Venturi vacuum pulling it also.
Most of the energy produced on a wind turbine comes from the airfoil and not from the pressure on the front of the blade. We should focus on this and maximize the torque harvest with it. If we can turn the 13 mph wind into a 21 mph wind by means of the venturi effect and then diffuse and augment it off the front cone to 32 mph (Betz Limit) and use the low pressure traveling faster (airfoil) without losing energy, because it is not being stopped by any obstacle, we get a stronger lift effect on our airfoils.
This would all take effect at the outer edge of the turbine wheel to take advantage of the maximum leverage which is most likely the largest gainer of torque. We must have some pressure on the front of the blade to get some push, but it will be from the 32-mph wind speed that we can extract 59% of the energy and possibly more from the blade design that increases the airfoil lift. We will get a small low-pressure pocket behind each blade, plus some turbulence, which comes with it, but the wind accelerator should pull this out as the blades are moving sideways to have the incoming wind blow the low-pressure pockets out and release it at 13 mph behind the unit.
The front point of the blade must divide the incoming wind with pressure on the front of the blade and an equal amount on the back of the blade (airfoil) so we have an even push and pull. Then we get the full effect of the airfoil and the push on the front of the blade. Here some Devinci drawings of the blade, weather vane, and front and rear cowling edges.
All support bars that come in contact with the wind must be elongated football shaped to be aerodynamic including the spokes on the turbine wheel. There must also be a support bar directly in front and directly behind the turbine wheel (like the fork blades on the front wheel of a bicycle) to eliminate any movement of the center shaft, causing vibration or frequencies.
The inside of the cowling should be anodized flat black along with the blades to hide any blade movement. The outside should be anodized semi-gloss grey and both the inside and outside should have golf ball dimples to prevent flow separation (boundary layer).
Most likely a direct drive will work best but we should check out torque converters and belt drive methods to get a smooth operation in the low, rough and tumbling winds of residential settings. The flywheel will help with this.
The turbine wheel will be connected to a magnetic bearing that rotates on the center shaft. Need to find the best way to transfer the torque to the best generator/generators.
The cowling could be made out of 1-inch square extruded aluminum tubing with EPS (extruded polystyrene) to support the space inside. The front and rear of the edges of the cowling need to be like the drawing included above and must be calculated in the Betz Limit so not to bottleneck the unit.
Also, need a stainless spring steel wire screen on the front and rear openings for bird and bat protection. The generator can be attached to the center shaft and for easy maintenance, a shaft coupling made into the center shaft. We need a turret and slip ring on the top of the monopole to turn the unit into the wind by tail fin, wind accelerator, or by a weather vane that controls a ball screw for directional wind control.
A tilt down (Hydraulic Gin Pole) monopole for easy maintenance purposes. The maintenance crew can own it and will keep people from doing their own maintenance for safety and legality reasons. Wireless monitoring of the harvest by customer and power company which also includes wind speed, wind direction, barometer, etc…
Will most likely need various sizes of monopoles for residential, farms, commercial, and community uses.
Will we need a braking system as the downshifting system and boundary layer may eliminate a need for it? If so, an umbrella style shut down system would prevent the wind from entering the unit and would essentially stop the unit. This could be made inside the front cone and would include the tip of the cone and slide forward on the center shaft while expanding out like an umbrella. Going back, it would enter back into the front cone and the tip would seal against the rest of the cone.
Build the flywheel into the outer ring and blades if necessary. Test blades for best angle, twist, number of them, length, and width. The entire unit must be balanced on the monopole.
Is there a counteract for the gyroscope effect when the unit moves into a new wind direction? Or do we really need it?
Build the cowling and turbine in quadrants for assembly on site or build it totally assembled.
Check out whale power: https://asknature.org/idea/tubercle-technology-blades/#.WFiBwvkrKM8
Check out Dyson fan: https://www.youtube.com/watch?v=4WNcjkZ6d0w
Check out aerodynamics: http://www.explainthatstuff.com/aerodynamics.html