(Press-News.org) Simple 'blast' fences called baffles could deliver improvements in air quality for people living near airports, new research has found.
Placed behind a runway, the baffles could serve as a 'virtual chimney', funnelling emissions from aircraft engines upwards where they can disperse more effectively, thereby reducing the environmental impact on people living nearby.
Prototype baffles have been tested by a team of researchers from Manchester Metropolitan University, Cranfield University, University of Southampton and the University of Cambridge, with funding from the Engineering and Physical Sciences Research Council (EPSRC).
After preliminary wind tunnel testing of various baffle shapes carried out by Cranfield University, an array of three rows of baffles was tested using laser scanning (Lidar, which is the optical equivalent of Radar) and chemical sensor techniques at Cranfield Airport in Bedfordshire. This demonstrated that the aircraft exhaust plume could be made to leave the ground within the airport's boundary fence, using prototype baffles of less than a man's height and constructed out of low-cost agricultural windbreak netting on lightweight frames.
Dr Mike Bennett, who led the project, says: "Airfield surfaces are typically covered with grass, over which the wind can blow freely. An array of baffles makes the surface rough in an aerodynamic sense. This sucks the momentum out of the exhaust jet, allowing its natural buoyancy to come into play. By suitably angling the baffles, we can also give the exhaust an upwards push, encouraging it to rise away from the ground.
"The baffles we tested were tilted at angles between 40° and 60° in order to optimise this vertical flow – and to ensure the baffles didn't blow over! Although the exhaust will still disperse to the ground eventually, it will do so at a lower concentration. We might hope to see a reduction in surface concentrations of around 50 per cent at the perimeter fence behind the place where aircraft are taking off."
Long-term ground-level nitrogen dioxide (NO2) concentrations around many major airports in Europe already exceed the legal limit enforced by the EU.
The aim of the trial was essentially to test the baffles' aerodynamics. As the prototype installation was temporary, it was constructed very differently from how a permanent installation might be made. Each baffle must be sufficiently robust to withstand the 80-90 knot blast from a jet engine, but flimsy enough to collapse harmlessly if an aircraft were to hit it. In the trial, this was achieved by restricting the prototype baffle widths to about two metres but it would be feasible to make them much narrower in a permanent installation. For full-scale use an area of baffles in the order of a thousand square metres would need to be erected behind a runway.
The tests also showed that the baffles dampened engine noise downstream by a modest amount and were helpful in reducing jet blast on the airport perimeter.
"There's no reason why baffles couldn't start to be installed at airports within two or three years," Dr Bennett says. "From the point of view of local air quality, they represent a quick, cheap supplement to developing low-NOx jet engines."
The project was carried out under the auspices of the EPSRC-funded Airport Energy Technologies Network (AETN), which was established in 2008 to undertake cutting-edge research in the field of aviation.
###
Notes for Editors
The development of the baffles has taken place as part of the three year project, under the Research Councils UK (RCUK) Energy Programme, 'A Study of Practical Abatement Techniques for Exhaust Jets from Commercial Aircraft', which concluded in the autumn of 2012 and received total EPSRC funding of £413,000. The University of Cambridge provided air quality monitoring expertise for the field tests. The Institute of Sound and Vibration Research in the University of Southampton carried out the acoustic studies.
The aircraft used in the field tests at Cranfield Airport was the Natural Environmental Research Council's (NERC) Facility for Airborne Atmospheric Measurements (www.faam.ac.uk/), a four-engined BAe146. The aircraft took off 12 times in all and on each occasion burned its engines for 5 -15 seconds at the end of the runway prior to take-off.
Lidar is the optical equivalent of radar. A pulsed ultra-violet laser beam was scanned through the exhaust plume in order to monitor the plume's dispersion.
The initial projects associated with the AETN were the outputs of an EPSRC Sandpit event in November 2009. Sandpits are intensive discussion forums where free thinking is encouraged in order to delve deep into specific issues and identify innovative solutions.
The Engineering and Physical Sciences Research Council (EPSRC) is the UK's main agency for funding research in engineering and physical sciences. EPSRC invests around £800 million a year in research and postgraduate training, to help the nation handle the next generation of technological change. The areas covered range from information technology to structural engineering, and mathematics to materials science. This research forms the basis for future economic development in the UK and improvements for everyone's health, lifestyle and culture. EPSRC works alongside other Research Councils with responsibility for other areas of research. The Research Councils work collectively on issues of common concern via Research Councils UK.
The Research Councils UK (RCUK) Energy Programme aims to position the UK to meet its energy and environmental targets and policy goals through world-class research and training. The Energy Programme is investing more than £530 million in research and skills to pioneer a low carbon future. This builds on an investment of £360 million over the past five years.
Led by the Engineering and Physical Sciences Research Council (EPSRC), the Energy Programme brings together the work of EPSRC and that of the Biotechnology and Biological Sciences Research Council (BBSRC), the Economic and Social Research Council (ESRC), the Natural Environment Research Council (NERC), and the Science and Technology Facilities Council (STFC).
The RCUK Energy Programme works closely with more than 500 public and private sector organizations and presently has 1,100 active collaborative projects. The Programme is helping the UK government make evidence-based decisions and policy.
Manchester Metropolitan University is the largest campus-based undergraduate university in the UK, with a total student population of more than 37,000 and an emphasis on vocational education and employability. With a history dating back 150 years, it was awarded university status in 1992. http://www2.mmu.ac.uk/
For more information contact:
Dr Mike Bennett, Manchester Metropolitan University, tel: 0161 247 6727, e-mail: m.bennett@mmu.ac.uk
Images are available from the EPSRC Press Office. Contact telephone 01793 444404, e-mail: pressoffice@epsrc.ac.uk
Image details and suggested caption:
Test 1, test 2 and test 3. Jpgs: Testing the baffles at Cranfield airport
The humble 'virtual chimney' fences that could reduce the impact of airport pollution
2013-01-31
ELSE PRESS RELEASES FROM THIS DATE:
Disulfiram: New support for an old addiction drug
2013-01-31
Philadelphia, PA, January 31, 2013 – Disulfiram was the first medication approved for the treatment of alcoholism over 50 years ago. It works, at least in part, by preventing the metabolism of an alcohol by-product, acetaldehyde. High levels of acetaldehyde in the body quickly cause unpleasant symptoms, including nausea, vomiting, headache, and accelerated heart rate. Thus, disulfiram provides a very strong incentive to avoid drinking.
Beginning in the late 1990s, a series of studies conducted at Yale University found that disulfiram reduced the consumption of cocaine, ...
Protein origami: Quick folders are the best
2013-01-31
Proteins are elementary building blocks of life. They often perform vital functions. In order to become active, proteins have to fold into three-dimensional structures. Misfolding of proteins leads to diseases such as Alzheimer's or Creutzfeld-Jakob. So which strategies did nature develop over the course of evolution to improve protein folding?
To examine this question, the chemist Dr. Frauke Gräter (Heidelberg Institute for Theoretical Studies) looked far back into the history of the Earth. Together with her colleague Prof. Gustavo Caetano-Anolles at the University of ...
A possible answer for protection against chemical/biological agents, fuel leaks, and coffee stains
2013-01-31
A recent discovery funded by the Air Force Office of Scientific Research (AFOSR) may very well lead to a process that not only benefits every uniformed service member of the Department of Defense, but everyone else as well: protection from Chemical/Biological agents, to self-cleaning apparel, to effortless thermal management, to fuel purification as well as enhanced control of leaks—especially oil and fuels.
In 2006, AFOSR Program Manager Dr. Charles Lee funded Professor Gareth McKinley at the Massachusetts Institute of Technology exploring nanocomposite technology ...
Second-generation CT scanner substantially reduces radiation exposure
2013-01-31
OAK BROOK, Ill. (January 31, 2013) – Researchers using a newly approved advanced computed tomography (CT) system were able to significantly reduce radiation exposure in patients undergoing coronary CT angiography (CCTA), according to a new study published online in the journal Radiology.
"Radiation exposure during diagnostic imaging is a substantial public concern," said Marcus Y. Chen, M.D., lead author of the study from the advanced cardiovascular imaging laboratory at the National Institutes of Health in Bethesda, Md. "Minimizing radiation exposure while maintaining ...
Corn cobs eyed for bioenergy production
2013-01-31
This press release is available in Spanish.
Corn crop residues are often left on harvested fields to protect soil quality, but they could become an important raw material in cellulosic ethanol production. U.S. Department of Agriculture (USDA) research indicates that soil quality would not decline if post-harvest corn cob residues were removed from fields.
This work, led by Agricultural Research Service (ARS) soil scientist Brian Wienhold, supports the USDA priority of developing new sources of bioenergy. ARS is USDA's chief intramural scientific research agency.
Wienhold ...
Gum disease found to worsen infection in animal model of AIDS
2013-01-31
Texas Biomed scientists in San Antonio have found that moderate gum disease in an animal model exposed to an AIDS- like virus had more viral variants causing infection and greater inflammation. Both of these features have potential negative implications in long term disease progression, including other kinds of infections, the researchers say in a new report.
The public health message from the study is that even mild inflammation in the mouth needs to be controlled because it can lead to more serious consequences, said Luis Giavedoni, Ph. D, a Texas Biomed virologist and ...
Flat boron by the numbers
2013-01-31
It would be a terrible thing if laboratories striving to grow graphene from carbon atoms kept winding up with big pesky diamonds.
"That would be trouble, cleaning out the diamonds so you could do some real work," said Rice University theoretical physicist Boris Yakobson, chuckling at the absurd image.
Yet something like that keeps happening to experimentalists working to grow two-dimensional boron. Boron atoms have a strong preference to clump into three-dimensional shapes rather than assemble into pristine single-atom sheets, like carbon does when it becomes graphene. ...
New study highlights impact of environmental change on older people
2013-01-31
Recent natural disasters illustrate vulnerability of older people: majority of deaths from the Great East Japan Earthquake (2011) and Hurricane Katrina (2005) occurred among older people.
Researchers at the Stockholm Environment Institute at the University of York and Simon Fraser University's Gerontology Research Centre in Canada are calling for better awareness among policy makers and the public of the impact climate change and deteriorating environmental quality will have on an ageing population.
According to UN projections, by 2050, nearly 25 per cent of the global ...
UNC study may lead to treatments that are effective against all MRSA strains
2013-01-31
CHAPEL HILL, N.C. – In the last decade, a new strain of MRSA has emerged that can spread beyond hospital walls, putting everyone at risk of contracting the dangerous bacterial infection. This particular strain of MRSA – known as USA300 – contains a chunk of genes not shared by any other strains, though it is unclear how this unique genetic material enables the bacteria to survive and persist in the community.
Now, research from the University of North Carolina School of Medicine has pinpointed a gene that causes the infection to linger on the skin longer than other strains, ...
How the tilt of a cell-surface receptor prevents cancer
2013-01-31
January 31, 2013, New York, NY and Brussels, Belgium – Clear communication between cells is essential to every aspect of the body's internal function. But since cells can't talk, or send emails, how do they communicate?
The answer, in a nutshell, is by dispatching signaling molecules that selectively bind to protein receptors on the outer surface of other cells with which they must "talk." This activates the tail end of such receptors inside the cell, initiating a cascade of enzymatic reactions, or signaling pathways that reach into the nucleus, turning genes on and off. ...