Wind

Dec 5 2011

Orion continues to make a splash

ScienceDaily (Dec. 5, 2011) — Testing continues at NASA Langley Research Center as the 18,000-pound (8,164.6 kg) Orion test article took its seventh splash into the Hydro Impact Basin Dec. 1.

Orion, NASA’s next deep space exploration vehicle, will carry astronauts into space, provide emergency abort capability, sustain the crew during space travel, and ensure safe re-entry and landing.

The testing, which began in this summer, simulates different water landing scenarios and takes into account different velocities, parachute deployments, entry angles, wave heights and wind conditions that Orion may face when landing in the Pacific Ocean.

“We are doing several of these tests to look at the operational envelope for the Orion landing conditions and the analysts need as much data as we can possibly give them,” said Lynn Bowman, SPLASH project manager. “In order to do it in as few cases possible, we have to look at these critical cases, which is not your average landing scenario or sea condition.”

The Dec. 1 test was all about the heat shield and how much it would flex after hitting the water at a slightly different angle. Sea conditions simulated a low-wind swell case.

The test article was only two feet above the water before it dropped pancake-style into the water. It traveled about 7 mph (11.26 kph).

There are more than 150 sensors on the test article that record data during each test drop. The results of these initial tests will help improve the design for the actual flight vehicle.

The last drop of the year is tentatively scheduled for Tuesday, Dec. 13.

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Article source: http://www.sciencedaily.com/releases/2011/12/111205101355.htm

By jimmy • Wind • 0 • Tags: Wind Power

Nov 16 2011

Why solar wind is rhombic-shaped: Temperature and energy equipartition in cosmic plasmas explained

ScienceDaily (Nov. 15, 2011) — Why the temperatures in the solar wind are almost the same in certain directions, and why different energy densities are practically identical, was until now not clear. With a new approach to calculating instability criteria for plasmas, Bochum researchers led by Prof. Dr. Reinhard Schlickeiser (Chair for Theoretical Physics IV) have solved both problems at once. They were the first to incorporate the effects of collisions of the solar wind particles in their model. This explains experimental data significantly better than previous calculations and can also be transferred to cosmic plasmas outside our solar system.

The scientists report on their findings in Physical Review Letters.

Temperatures and pressures in the cosmic plasma

The solar wind consists of charged particles and is permeated by a magnetic field. In the analysis of this plasma, researchers investigate two types of pressure: the magnetic pressure describes the tendency of the magnetic field lines to repel each other, the kinetic pressure results from the momentum of the particles. The ratio of kinetic to magnetic pressure is called plasma beta and is a measure of whether more energy per volume is stored in magnetic fields or in particle motion. In many cosmic sources, the plasma beta is around the value one, which is the same as energy equipartition. Moreover, in cosmic plasmas near temperature isotropy prevails, i.e. the temperature parallel and perpendicular to the magnetic field lines of the plasma is the same.

Explaining satellite data

For over a decade, the instruments of the near-earth WIND satellite have gathered various solar wind data. When the plasma beta measured is plotted against the temperature anisotropy (the ratio of the perpendicular to the parallel temperature), the data points form a rhombic area around the value one. “If the values move out of the rhombic configuration, the plasma is unstable and the temperature anisotropy and the plasma beta quickly return to the stable region within the rhombus” says Prof. Schlickeiser. However, a specific, detailed explanation of this rhombic shape has, until now, been lacking, especially for low plasma beta.

Collisions in the solar wind

In previous models it was assumed that, due to the low density, the solar wind particles do not directly collide, but only interact via electromagnetic fields. “Such assumptions are, however, no longer justified for small plasma beta, since the damping due to particle collisions needs to be taken into account” explains Dipl.-Phys. Michal Michno. Prof. Schlickeiser’s group included this additional damping in their model, which led to new rhombic thresholds i.e. new stability conditions. The Bochum model explains the solar wind data measured significantly better than previous theories.

Universally valid solution

The new model can be applied to other dilute cosmic plasmas which have densities, temperatures and magnetic field strengths similar to the solar wind. Even if the diagram of temperature anisotropy and plasma beta does not have exactly the rhombic shape that the researchers found for the solar wind, the newly discovered mechanism predicts that the values are always close to one. In this way, the theory also makes an important contribution to the explanation of the energy equipartition in cosmic plasmas outside of our solar system.

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Journal Reference:

1. R. Schlickeiser, M. Michno, D. Ibscher, M. Lazar, T. Skoda. Modified Temperature-Anisotropy Instability Thresholds in the Solar Wind. Physical Review Letters, 2011; 107 (20) DOI: 10.1103/PhysRevLett.107.201102

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Article source: http://www.sciencedaily.com/releases/2011/11/111115073934.htm

By jimmy • Wind • 0 • Tags: Wind Power

Sep 14 2011

Double jeopardy: Building codes may underestimate risks due to multiple hazards

ScienceDaily (Sep. 13, 2011) — As large parts of the United States recover from nature’s one-two punch — an earthquake followed by Hurricane Irene — building researchers from the National Institute of Standards and Technology (NIST) warn that a double whammy of seismic and wind hazards can increase the risk of structural damage to as much as twice the level implied in building codes.

This is because current codes consider natural hazards individually, explains NIST’s Dat Duthinh, a research structural engineer. So, if earthquakes rank as the top threat in a particular area, local codes require buildings to withstand a specified seismic load. In contrast, if hurricanes or tornadoes are the chief hazard, homes and buildings must be designed to resist loads up to an established maximum wind speed.

In a timely article published in the Journal of Structural Engineering, Duthinh, NIST Fellow Emil Simiu and Chiara Crosti (now at the University of Rome) challenge this compartmentalized approach. They show that in areas prone to both seismic and wind hazards, such as South Carolina, the risk that design limits will be exceeded can be as much as twice the risk in regions where only one hazard occurs, even accounting for the fact that these multiple hazards almost never occur simultaneously. As a consequence, buildings designed to meet code requirements in these double-jeopardy locations “do not necessarily achieve the level of safety implied,” the researchers write.

Simiu explains by analogy: a motorcycle racer who takes on a second job as a high-wire performer. “By adding this new occupation, the racer increases his risk of injury, even though the timing and nature of the injuries sustained in a motorcycle accident or in a high-wire mishap may differ,” he says. “Understandably, an insurer would raise the premium on a personal injury policy to account for the higher level of risk.”

The researchers developed a method to assess risks due to wind and earthquakes using a common metric of structural resistance. With a consistent measure (the maximum lateral deflection), the combined risk of failure can be compared to the risk that design limits will be exceeded in regions vulnerable to only one of the hazards, the basis for safety requirements specified in current building codes.

They demonstrate their approach on three different configurations of a 10-story steel-frame building. One of the configurations used so-called reduced beam sections (RBS) to connect girders to columns. RBS technology was developed after California’s Northridge earthquake in 1994, which resulted in significant structural damage in new and old buildings due to unanticipated brittle fractures in frame connections. Shaped like a dog bone, tapered RBS connections made the frames more ductile — better able to deflect without breaking.

In this case study, the researchers found that RBS connections do not decrease the risk that a steel-frame building will exceed its design limit when used in a region exposed to high winds or a region exposed to high winds and earthquakes. Consequently, the risk of failure doubled under dual-hazard conditions, when those conditions are of similar severity. However, they note that RBS connections can decrease the risk that limits associated with seismic design will be exceeded during the structure’s life.

The researchers are continuing to extend their methodology and are proposing modifications to building codes.

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The above story is reprinted (with editorial adaptations by ScienceDaily staff) from materials provided by National Institute of Standards and Technology (NIST).

Journal Reference:

1. Chiara Crosti, Dat Duthinh, Emil Simiu. Risk Consistency and Synergy in Multihazard Design. Journal of Structural Engineering, 2011; 137 (8): 844 DOI: 10.1061/(ASCE)ST.1943-541X.0000335

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Article source: http://www.sciencedaily.com/releases/2011/09/110913172713.htm

By jimmy • Wind • 0 • Tags: Wind Power

Aug 28 2011

Astrophysicists solve 40-year-old Mariner 5 solar wind problem: Turbulence doesn’t go with the flow

ScienceDaily (Aug. 26, 2011) — Research led by astrophysicists at the University of Warwick has resolved a 40-year-old problem with observations of turbulence in the solar wind first made by the probe Mariner 5. The research resolves an issue with what is by far the largest and most interesting natural turbulence lab accessible to researchers today.

Our current understanding tells us that turbulence in the solar wind should not be affected by the speed and direction of travel of that solar wind. However when the first space probes attempted to measure that turbulence they found their observations didn’t quite match that physical law. The first such data to be analysed from Mariner 5 in 1971 found a small but nonetheless irritatingly clear pattern in the turbulence perpendicular to both the direction of the travel and the magnetic field the solar wind was travelling through.

While it was an irritating aberration the affect was relatively small and has been essentially ignored by physicists until now. However the most recent space missions to look at the solar wind, such as the Cluster mission, are examining it with such sensitive and highly accurate modern instrumentation that what was once a small aberration was threatening to become a significant stumbling block to us getting a deeper understanding of what is going on in the solar wind — which is effectively the solar system’s largest and most interesting natural turbulence lab.

Research led by Andrew Turner and Professor Sandra Chapman in Centre for Fusion, Space and Astrophysics at the University of Warwick has found a solution to this 40 year old problem. The research team looked at data from the Cluster mission and they also created a virtual model of how magnetohydrodynamic (MHD) turbulence builds up in the Solar wind. They then flew a virtual space probe through that virtual model in a range of directions unlike the single direction of travel open to a probe such as Mariner 5.

University of Warwick researcher Andrew Turner said that what they found was that: “The analysis clearly showed that when all these results were considered together any correlation between changes in the turbulence in the solar wind and the direction of travel simply disappeared. The observed non-axisymmetric anisotropy may simply arise as a sampling effect of using just one probe taking a single particular path through the solar wind.”

The research paper is published in Physical Review Letters and is by A.J. Turner, S. Chapman B. Hnat Centre for Fusion, Space and Astrophysics, University of Warwick; G. Gogoberidze, Centre for Fusion, Space and Astrophysics, University of Warwick and the Institute of Theoretical Physics, Ilia State University; and W.C.Müller of the Max-Planck-Institut für Plasmaphysik.

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Article source: http://www.sciencedaily.com/releases/2011/08/110826085147.htm

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Jul 30 2011

Motorcycle helmets hard on hearing

ScienceDaily (July 29, 2011) — Motorcycle helmets, while protecting bikers’ brains, may also be contributing to hearing loss. Scientists mapped the airflow and noise patterns to find out why.

The distinctive roar of a Harley’s engine is loud, but studies have revealed the biggest source of noise for motorcyclists is actually generated by air whooshing over the riders’ helmets. Even at legal speeds, the sound can exceed safe levels. Now, scientists have identified a key source of the rushing din. Researchers from the University of Bath and Bath Spa University placed motorcycles helmets atop mannequin heads, mounted them in a wind tunnel, and turned on the fans.

By placing microphones at different locations around the helmet and at the mannequin’s ear, the researchers found that an area underneath the helmet and near the chin bar is a significant source of the noise that reaches riders’ sensitive eardrums. The team also investigated how helmet angle and wind speed affected the loudness. Future tests will move beyond the wind tunnel to real-life riders on the open road.

The findings, described in the Journal of the Acoustical Society of America, may one day be used to design quieter helmets, saving riders’ ears for the enjoyment of hard biker rock, the researchers say.

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The above story is reprinted (with editorial adaptations by ScienceDaily staff) from materials provided by American Institute of Physics, via EurekAlert!, a service of AAAS.

Journal Reference:

1. J. Kennedy, O. Adetifa, M. Carley, N. Holt and I. Walker. Aeroacoustic sources of motorcycle helmet noise. Journal of the Acoustical Society of America, 2011

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Article source: http://www.sciencedaily.com/releases/2011/07/110729175559.htm

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Jul 14 2011

Wind-turbine placement produces tenfold power increase, researchers say

ScienceDaily (July 13, 2011) — The power output of wind farms can be increased by an order of magnitude — at least tenfold — simply by optimizing the placement of turbines on a given plot of land, say researchers at the California Institute of Technology (Caltech) who have been conducting a unique field study at an experimental two-acre wind farm in northern Los Angeles County.

A paper describing the findings — the results of field tests conducted by John Dabiri, Caltech professor of aeronautics and bioengineering, and colleagues during the summer of 2010 — appears in the July issue of the Journal of Renewable and Sustainable Energy.

Dabiri’s experimental farm, known as the Field Laboratory for Optimized Wind Energy (FLOWE), houses 24 10-meter-tall, 1.2-meter-wide vertical-axis wind turbines (VAWTs) — turbines that have vertical rotors and look like eggbeaters sticking out of the ground. Half a dozen turbines were used in the 2010 field tests.

Despite improvements in the design of wind turbines that have increased their efficiency, wind farms are rather inefficient, Dabiri notes. Modern farms generally employ horizontal-axis wind turbines (HAWTs) — the standard propeller-like monoliths that you might see slowly turning, all in the same direction, in the hills of Tehachapi Pass, north of Los Angeles.

In such farms, the individual turbines have to be spaced far apart — not just far enough that their giant blades don’t touch. With this type of design, the wake generated by one turbine can interfere aerodynamically with neighboring turbines, with the result that “much of the wind energy that enters a wind farm is never tapped,” says Dabiri. He compares modern farms to “sloppy eaters,” wasting not just real estate (and thus lowering the power output of a given plot of land) but much of the energy resources they have available to them.

Designers compensate for the energy loss by making bigger blades and taller towers, to suck up more of the available wind and at heights where gusts are more powerful. “But this brings other challenges,” Dabiri says, such as higher costs, more complex engineering problems, a larger environmental impact. Bigger, taller turbines, after all, mean more noise, more danger to birds and bats, and — for those who don’t find the spinning spires visually appealing — an even larger eyesore.

The solution, says Dabiri, is to focus instead on the design of the wind farm itself, to maximize its energy-collecting efficiency at heights closer to the ground. While winds blow far less energetically at, say, 30 feet off the ground than at 100 feet, “the global wind power available 30 feet off the ground is greater than the world’s electricity usage, several times over,” he says. That means that enough energy can be obtained with smaller, cheaper, less environmentally intrusive turbines — as long as they’re the right turbines, arranged in the right way.

VAWTs are ideal, Dabiri says, because they can be positioned very close to one another. This lets them capture nearly all of the energy of the blowing wind and even wind energy above the farm. Having every turbine turn in the opposite direction of its neighbors, the researchers found, also increases their efficiency, perhaps because the opposing spins decrease the drag on each turbine, allowing it to spin faster (Dabiri got the idea for using this type of constructive interference from his studies of schooling fish).

In the summer 2010 field tests, Dabiri and his colleagues measured the rotational speed and power generated by each of the six turbines when placed in a number of different configurations. One turbine was kept in a fixed position for every configuration; the others were on portable footings that allowed them to be shifted around.

The tests showed that an arrangement in which all of the turbines in an array were spaced four turbine diameters apart (roughly 5 meters, or approximately 16 feet) completely eliminated the aerodynamic interference between neighboring turbines. By comparison, removing the aerodynamic interference between propeller-style wind turbines would require spacing them about 20 diameters apart, which means a distance of more than one mile between the largest wind turbines now in use.

The six VAWTs generated from 21 to 47 watts of power per square meter of land area; a comparably sized HAWT farm generates just 2 to 3 watts per square meter.

“Dabiri’s bioinspired engineering research is challenging the status quo in wind-energy technology,” says Ares Rosakis, chair of Caltech’s Division of Engineering and Applied Science and the Theodore von Kármán Professor of Aeronautics and professor of mechanical engineering. “This exemplifies how Caltech engineers’ innovative approaches are tackling our society’s greatest problems.”

“We’re on the right track, but this is by no means ‘mission accomplished,’” Dabiri says. “The next steps are to scale up the field demonstration and to improve upon the off-the-shelf wind-turbine designs used for the pilot study.” Still, he says, “I think these results are a compelling call for further research on alternatives to the wind-energy status quo.”

This summer, Dabiri and colleagues are studying a larger array of 18 VAWTs to follow up last year’s field study. Video and images of the field site can be found at http://dabiri.caltech.edu/research/wind-energy.html.

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The above story is reprinted (with editorial adaptations by ScienceDaily staff) from materials provided by California Institute of Technology. The original article was written by Kathy Svitil.

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Article source: http://www.sciencedaily.com/releases/2011/07/110713092153.htm

By jimmy • Wind • 0 • Tags: Wind Power

Jun 15 2011

Why Did Cowboys Facility Collapse?

ScienceDaily (Oct. 7, 2009) — A fabric-covered, steel frame practice facility owned by the National Football League’s Dallas Cowboys collapsed under wind loads significantly less than those required under applicable design standards, according to a report released on October 6 for public comment by the Commerce Department’s National Institute of Standards and Technology (NIST).

Located in Irving, Texas, the facility collapsed on May 2, 2009, during a severe thunderstorm. Twelve people were injured, one seriously.

Based on the national standards for determining loads and for designing structural steel buildings, NIST researchers studying the Cowboys facility found that the May 2 wind load demands on the building’s framework—a series of identical, rib-like steel frames supporting a tensioned fabric covering—were greater than the capacity of the frame to resist those loads.

Assumptions and approaches used in the design of the Cowboys facility led to the differences between the values originally calculated for the wind load demand and structural frame capacity compared to those derived by the NIST researchers. For instance, the NIST researchers included internal wind pressure due to the presence of vents and multiple doors in their wind load calculations because they classified the building as “partially enclosed” rather than “fully enclosed” as stated in the design documents. The NIST researchers also determined that the building’s fabric could not be relied upon to provide lateral bracing (additional perpendicular support) to the frames in contrast to what was stated in the design documents and that the expected wind resistance of the structure did not account for bending effects in some members of the frame.

“Our investigation found that the facility collapsed under a wind load that a building of this type would be expected to withstand,” said study leader John Gross. “As a result of our findings, NIST is recommending that fabric-covered steel frame structures be evaluated to ensure the adequate performance of the structural framing system under design wind loads.”

The NIST report recommends that such evaluations determine whether or not: (1) the fabric covering provides lateral bracing for structural frames considering its potential for tearing; (2) the building should be considered partially enclosed or fully enclosed based on the openings that may be present around the building’s perimeter; and (3) the failure of one or a few frame members may propagate, leading to a partial or total collapse of the structure.

Shortly after the Cowboys facility’s collapse, NIST sent a reconnaissance team of three structural engineers to assess the failed structure and wind damage in the surrounding area, and collect relevant data such as plans, specifications and design calculations. Using the data acquired during the reconnaissance, the NIST study team developed a computer model of a typical structural frame used in the practice facility and then studied the frame’s ability to resist forces under two wind conditions: the wind loads based on the design standard wind speed of 90 miles per hour and the actual wind loads based on conditions at the time of the collapse.

NIST worked with the National Oceanic and Atmospheric Administration’s (NOAA) National Severe Storms Laboratory to estimate the wind conditions at the time of collapse. The researchers determined that, at the time of collapse, the wind was blowing predominantly from west to east, perpendicular to the long side of the building. Maximum wind speed gusts at the time of collapse were estimated to be in the range of 55 to 65 miles per hour—well below the design wind speed of 90 miles per hour in the national standard for wind loads. The center of a microburst (a small, intense downdraft which results in a localized area of strong winds) associated with the May 2 thunderstorm was located about one mile southwest of the structure at the time of collapse.

According to the NIST and NOAA researchers, the wind field in the vicinity of the Cowboys facility at the time of collapse was consistent with design standards and not unusual.

Based on their study of the wind conditions at the time of collapse and the structural response, the NIST researchers determined the following likely collapse sequence:

• Buckling of the inner chord (inner side of the roof truss) of a frame in a section of the roof on the east side resulted in the formation of a kink in the frame.
• Failures of the east and west “knees” (connections between the side walls and the roof) allowed the frame to sway eastward with the wind.
• Compressive failure of the east side at the roof’s highest point (ridge) led to fractures of the nearby inner and outer chords in the vicinity of the ridge.
• A progression of frame failures throughout the structure resulted in total structural collapse.

The draft report is available online at http://www.bfrl.nist.gov/investigations/investigations.htm.

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The above story is reprinted (with editorial adaptations by ScienceDaily staff) from materials provided by National Institute of Standards and Technology (NIST).

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Disclaimer: This article is not intended to provide medical advice, diagnosis or treatment. Views expressed here do not necessarily reflect those of ScienceDaily or its staff.

Article source: http://www.sciencedaily.com/releases/2009/10/091006173553.htm

By jimmy • Wind • 0 • Tags: Wind Power

Jun 15 2011

For Safer Emergencies, Give Your Power Generator Some Space

ScienceDaily (Oct. 10, 2009) — To subdue the steaming heat of hurricanes or to thaw out during a blizzard, gasoline-powered, portable generators are a lifeline during weather emergencies when homes are cut off without electricity. But these generators emit poisonous carbon monoxide—a single generator can produce a hundred times more of the colorless, odorless gas than a modern car’s exhaust.

New research from the National Institute of Standards and Technology (NIST) shows that to prevent potentially dangerous levels of carbon monoxide, users may need to keep generators farther from the house than previously believed—perhaps as much as 25 feet.

Up to half of the incidents of non-fatal carbon monoxide (CO) poisoning reported in the 2004 and 2005 hurricane seasons involved generators run within 7 feet of the home, according to the U.S. Centers for Disease Control and Prevention (CDC).

Carbon monoxide can enter a house through a number of airflow paths, such as a door or window left open to accommodate the extension cord that brings power from the generator into the house. While some guidance recommends 10 feet from open windows as a safe operating distance, NIST researcher Steven Emmerich says the “safe” operating distance depends on the house, the weather conditions and the unit. A generator’s carbon monoxide output is usually higher than an automobile’s, he says, because most generators do not have the sophisticated emission controls that cars do.

“People need to be aware that generators are potentially deadly and they need to educate themselves on proper use,” Emmerich says. With funding from CDC, NIST researchers are gathering reliable data to support future CDC guidance.

NIST building researchers simulated multiple scenarios of a portable generator operating outside of a one-story house, using both a test structure and two different computer models—the NIST-developed CONTAM indoor air quality model and a computational fluid dynamics model.

The simulations included factors that could be controlled by humans, such as generator location, exhaust direction and window-opening size, and environmental factors such as wind, temperature and house dimensions. In the simulations the generator was placed at various distances from the house and tested under different weather conditions.

“We found that for the house modeled in this study,” researcher Leon Wang says, “a generator position 15 feet away from open windows was not far enough to prevent carbon monoxide entry into the house.”

Winds perpendicular to the open window resulted in more carbon monoxide entry than winds at an angle, and lower wind speeds generally allowed more carbon monoxide in the house. “Slow, stagnant wind seems to be the worst case because it leads to the carbon monoxide lingering by the windows,” Wang explains. Researchers determined that placing the generator outside of the airflow recirculation regions near the open windows reduced carbon monoxide entry.

In the next phase of the study NIST will model a two-story house that researchers believe will interact with the wind differently. NIST researchers also have worked with the Consumer Product Safety Commission on related work. (See: “NIST to Study Hazards of Portable Gasoline-Powered Generators,” NIST Tech Beat, March 5, 2008.)

* L. Wang and S.J. Emmerich. Modeling the Effects of Outdoor Gasoline Powered Generator Use on Indoor Carbon Monoxide Exposures. (NIST Technical Note 1637,) 2009.

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The above story is reprinted (with editorial adaptations by ScienceDaily staff) from materials provided by National Institute of Standards and Technology (NIST).

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Disclaimer: This article is not intended to provide medical advice, diagnosis or treatment. Views expressed here do not necessarily reflect those of ScienceDaily or its staff.

Article source: http://www.sciencedaily.com/releases/2009/10/091006191351.htm

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Jun 15 2011

Research Continues On Secure, Mobile, Quantum Communications

ScienceDaily (Nov. 2, 2009) — Researcher Dr. David H. Hughes of the Air Force Research Laboratory in Rome, N.Y. is leading a team investigating long-distance, mobile optical links imperative for secure quantum communications capabilities in theater.

Hughes and his Air Force Office of Scientific Research-funded team have conducted high data-rate experiments using an optical laser link, a tool which exploits the quantum noise of light for higher security. The system uses adaptive optics for transmission of high data-rate video and audio signals over long distances.

AOptix Technologies, a developer of ultra-high bandwidth laser communication solutions for government and commercial markets has joined forces with AFOSR and AFRL to conduct flight tests at 10,000 feet to evaluate the performance of the high-altitude, air-to-ground, quantum communications links.

Up to this point, the challenge with free space optical links, which use fiber optics for transmission have been the turbulence or distortions from temperature differences that cause motion or wind in the atmosphere.

“When you transmit information through turbulence (motion in the atmosphere caused by turbulent cells or “wind”) it’s distorted just like the information coming from the light reflected off a distant, twinkling star to your eye. It’s fuzzy,” said Hughes. “You have to overcome that by using adaptive optics to rectify the distortion and get a better quality signal.”

As of right now, Hughes and his team have established an optical link without distortion in test situations at a distance of 35 kilometers in both stationary and flight situations. The next flight test will aim for increased altitudes to demonstrate further air-to-ground distances.

“If we can now put one link on the ground and one on a demo aircraft, it wouldn’t take much to apply the technology to operational aircraft for the Air Force,” said Hughes.

“This new capability may even save lives because it will enable the military to access ultra-high bandwidth ISR (intelligence, surveillance reconnaissance) information in real-time from various manned and unmanned airborne platforms,” said Dean Senner, President CEO of AOptix Technologies.

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The above story is reprinted (with editorial adaptations by ScienceDaily staff) from materials provided by Air Force Office of Scientific Research.

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Article source: http://www.sciencedaily.com/releases/2009/10/091027132959.htm

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