AVT Ideas for 2006

Atmospheric Vortex Tower  Built in the Summer of 2005Report on Experiments and Future Plans: 

Atmospheric Vortex Tower Built in the Summer of 2005 Report on Experiments and Future Plans January 25, 2008 Tom Fletcher

Photo of Vortex Tower: 

Photo of Vortex Tower

Vortex Tower Construction: 

Vortex Tower Construction A 48’ tall vortex tower was built using steel frame construction and plywood. It was determined that this was cheaper and more easily modified than a steel or concrete tower. Eight telephone poles were used to support the tower. We located the tower in a hot remote desert location away from any buildings. Castle Dale, Utah was chosen as the construction site. This tower was surrounded by black gravel up to a radius of 100 feet from the tower.

Wind Guide Lowest 12’ of tower.: 

Wind Guide Lowest 12’ of tower. 27’ 7.9’ 11.2’ Doors can slide to block wind Telephone poles

Wind Guide Upper 36’ of tower.: 

Wind Guide Upper 36’ of tower. No Doors With 1’ gaps

Heat Driven Vortices: 

Heat Driven Vortices Heat Sources were used to create a vortex A propane heater A fire in the middle using a mixture of gasoline and diesel fuel A large metal pan of boiling water The velocity of the vortex wind varied with the size of the heat source and the velocity of the ambient wind entering the tower from the sliding doors.

Vortices from Ambient Wind: 

Vortices from Ambient Wind Vortices were always going in the tower when horizontal wind was present. By opening the doors facing the incoming wind, the vortex wind velocity is amplified. One way doors with rubber hinges were proposed to capture the ambient wind. 16’ doors with rubber hinges were added to the upper section.

One way doors with rubber hingesfor Upper section of Tower: 

One way doors with rubber hinges for Upper section of Tower One way doors

Control of the Orifice: 

Control of the Orifice A floor was added at the 12 foot level just above the doors in order to create an orifice that would focus the vortex into the middle. The orifice had a 6 foot diameter. This enabled the formation of a central vortex. Without the orifice, the vortex wind in the tower flowed along the outside wall.

Floor with Orifice at the 12’ level: 

Floor with Orifice at the 12’ level Air spirals into the orifice and increases in velocity as it moves into the central vortex.

Observations: 

Observations Without horizontal wind we had to start the vortex artificially with a fire or propane burner. Heat from the surrounding black rock solar collector does not flow toward the tower in any appreciable amount. A glass solar collector or glass side on the tower is required to enable a true solar vortex.  A smaller structure should work just as well for experimental studies.

Photo of a Fire Whirl in the Tower: 

Photo of a Fire Whirl in the Tower

True Solar Dust Devil: 

True Solar Dust Devil A true dust devil from solar heating of the dust was not produced in the vortex tower because we didn’t have glass walls and the ground was shaded in the center. We learned that the heating of the dust to about 30 degrees F. hotter than the air above it is critical to initiating a dust devil vortex. A glass solar collector can also produce the necessary heat source for initiating a vortex.

Horizontal Wind Amplification: 

Horizontal Wind Amplification Amplification of the horizontal wind velocity with a vortex is an important concept that came out of this study that we plan to pursue further. By funneling the horizontal wind into a vortex we may be able to amplify the wind velocity and drive smaller wind turbines to produce more energy at lower turbine cost. The concept of one-way doors is an interesting idea that could be used to enable the wind amplification.

Control of the Orifice: 

Control of the Orifice The importance of the orifice was clearly demonstrated with this experiment. An orifice should be added at the top of the tower to enable a more optimal central vortex for the entire height of the tower. The relationship between the door size, orifice size, horizontal wind velocity and heat source size are all important variables.

Future Plans: 

Future Plans Add a small solar green house collector to help initiate a true solar vortex. Add windows and reflectors in an optimal way to create a true solar dust devil. Funnel horizontal wind into a vortex in order to amplify the wind velocity and drive smaller wind turbines that produce more energy at lower cost. Optimize size of doors, panels and orifice for amplification of vortex under various conditions.

Solar (Greenhouse) Collector: 

Solar (Greenhouse) Collector Vortex Tower Solar Collector Vortex Solar Energy

Dust Devil Vortex Tower: 

Dust Devil Vortex Tower North Reflective panels reflect solar energy down onto dust. Transparent panels permit solar heating of dust. Northern Hemisphere model The fuel is sun and dirt!

Vortex Wind Amplifier: 

Vortex Wind Amplifier Top View

Vortex Wind Amplifier: 

Vortex Wind Amplifier Flapping doors open or close to steer wind through the orifice at higher velocity.

Backup: 

Backup

Vortex Solar Tower Concept: 

Vortex Solar Tower Concept Solar towers must be very tall to create the temperature differential needed to create a strong wind to drive large turbines. The cost of building such a tall tower is prohibitive for most businesses. If the tower can be replaced by a controlled vortex then a vortex solar tower can be built at much reduced cost. Solar collectors attached to solar towers require large fields of expensive glass and supporting structures to collect the heat. If the collector can be removed or reduced in size, then the vortex solar collector can be built at reduced cost.

Progression from Solar Tower to Vortex Tower: 

Progression from Solar Tower to Vortex Tower

Possible benefits of adding a glass solar collector around the tower: 

Possible benefits of adding a glass solar collector around the tower Air is heated under the collector and cannot go up, but is forced laterally into the tower Less reliance on lateral wind to transfer heat from the black gravel to the tower Possible use of the collector as a greenhouse for agricultural purposes

Benefits Summary: 

Benefits Summary An Inexpensive vortex solar tower would be about 10 times less expensive to build than the currently proposed solar towers, which have been shown to be cost effective. Shrouded turbines at ground level are more efficient and require less space than large wind turbines. Costly solar collector can be reduced in size. Very low cost can make the virtual solar tower concept useful in regions of the world with fewer hours of sunshine.

Internet Links: 

Internet Links http://vortexengine.ca/ http://www.economist.com/printedition/displayStory.cfm?Story_ID=4455446 http://www.energybulletin.net/5258.html http://www.enviromission.com.au/