Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Perforating aircraft wings with minute holes could make for more efficient flying

14.01.2002


One way to make aeroplanes fly more efficiently is to drill millions of tiny holes in the leading edges of the wings. Like the dimples on a golf ball this has the effect of reducing drag. However, producing these holes on a manufacturing scale is not yet commercially feasible.

Researchers at Heriot-Watt University, funded by the Engineering and Physical Sciences Research Council, and the aerospace company BAE SYSTEMS, have carried out a series of fundamental studies on drilling such holes using laser beams. The results of the work are being assessed by BAE SYSTEMS to determine whether the airflow characteristics of holes produced in this way are suitable.

Dr Duncan Hand is a member of the research team. “It’s been known for a long time that arrays of millions of holes, 50 or 60 micrometres in diameter, on the leading edge of aircraft wings can improve the air flow characteristics around the wing,” he says. “But there’s been no cost-effective way of producing these holes accurately, quickly and cheaply – it is important to justify the increased manufacturing costs against any improvement in the aircraft’s efficiency.”



While conventional mechanical drilling techniques are insufficiently accurate and too slow for holes of this size and in these numbers, using lasers to drill the holes might be a feasible option. Here the energy of the laser melts or vaporises the metal, leaving a hole. By splitting the laser beam it would be possible to drill many holes simultaneously.

“If laser drilling is to be considered it’s necessary to know what sort of laser pulse is best, how much energy is needed, what are the most appropriate conditions – all these factors are important,” says Dr Hand.

The Heriot-Watt team has been examining two ways of laser drilling. One is using the laser in a ‘long pulse’ mode, where the pulse of laser energy lasts for around a millisecond. The other is a ‘short pulse’ mode, where the laser pulses are in the range of nanoseconds.

“For the short pulse mode you need many pulses to drill the hole, whereas for the longer pulse mode you only need a single pulse,” says Dr Hand. “While the shorter pulses produce holes which have more geometric uniformity, they take longer to drill. We also found that because the short pulses have a very high peak power, they tend to ionise the gases they come into contact with – both the air layer on the surface of the material and the vaporised metal.” This ionised gas, or plasma, can block a significant proportion of the laser energy.

The main issue with drilling with the longer pulse lasers is that the holes are less uniform. “There is a lot of interest in the variability of geometry of the holes,” says Dr Hand. “We have found that you can control certain parameters in the process to minimise the variability between holes, but there will always be an intrinsic variability. The main question is whether this variability is acceptable. That is something which is now being assessed.”



Jane Reck | alphagalileo

More articles from Transportation and Logistics:

nachricht German-British Research project for even more climate protection in the rail industry
28.05.2020 | Technische Universität Dresden

nachricht Delivery drones instead of postal vans?
22.04.2020 | Martin-Luther-Universität Halle-Wittenberg

All articles from Transportation and Logistics >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Restoring vision by gene therapy

Latest scientific findings give hope for people with incurable retinal degeneration

Humans rely dominantly on their eyesight. Losing vision means not being able to read, recognize faces or find objects. Macular degeneration is one of the major...

Im Focus: Small Protein, Big Impact

In meningococci, the RNA-binding protein ProQ plays a major role. Together with RNA molecules, it regulates processes that are important for pathogenic properties of the bacteria.

Meningococci are bacteria that can cause life-threatening meningitis and sepsis. These pathogens use a small protein with a large impact: The RNA-binding...

Im Focus: K-State study reveals asymmetry in spin directions of galaxies

Research also suggests the early universe could have been spinning

An analysis of more than 200,000 spiral galaxies has revealed unexpected links between spin directions of galaxies, and the structure formed by these links...

Im Focus: New measurement exacerbates old problem

Two prominent X-ray emission lines of highly charged iron have puzzled astrophysicists for decades: their measured and calculated brightness ratios always disagree. This hinders good determinations of plasma temperatures and densities. New, careful high-precision measurements, together with top-level calculations now exclude all hitherto proposed explanations for this discrepancy, and thus deepen the problem.

Hot astrophysical plasmas fill the intergalactic space, and brightly shine in stellar coronae, active galactic nuclei, and supernova remnants. They contain...

Im Focus: Biotechnology: Triggered by light, a novel way to switch on an enzyme

In living cells, enzymes drive biochemical metabolic processes enabling reactions to take place efficiently. It is this very ability which allows them to be used as catalysts in biotechnology, for example to create chemical products such as pharmaceutics. Researchers now identified an enzyme that, when illuminated with blue light, becomes catalytically active and initiates a reaction that was previously unknown in enzymatics. The study was published in "Nature Communications".

Enzymes: they are the central drivers for biochemical metabolic processes in every living cell, enabling reactions to take place efficiently. It is this very...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

Dresden Nexus Conference 2020: Same Time, Virtual Format, Registration Opened

19.05.2020 | Event News

Aachen Machine Tool Colloquium AWK'21 will take place on June 10 and 11, 2021

07.04.2020 | Event News

International Coral Reef Symposium in Bremen Postponed by a Year

06.04.2020 | Event News

 
Latest News

New image of a cancer-related enzyme in action helps explain gene regulation

05.06.2020 | Life Sciences

Silicon 'neurons' may add a new dimension to computer processors

05.06.2020 | Physics and Astronomy

Protecting the Neuronal Architecture

05.06.2020 | Life Sciences

VideoLinks
Science & Research
Overview of more VideoLinks >>>