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 Researchers 'count cars' -- literally -- to find a better way to control heavy traffic
10.08.2017 | Florida Atlantic University

nachricht From parking garage to smart multi-purpose garage
19.07.2017 | Fraunhofer-Institut für Arbeitswirtschaft und Organisation IAO

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: Fizzy soda water could be key to clean manufacture of flat wonder material: Graphene

Whether you call it effervescent, fizzy, or sparkling, carbonated water is making a comeback as a beverage. Aside from quenching thirst, researchers at the University of Illinois at Urbana-Champaign have discovered a new use for these "bubbly" concoctions that will have major impact on the manufacturer of the world's thinnest, flattest, and one most useful materials -- graphene.

As graphene's popularity grows as an advanced "wonder" material, the speed and quality at which it can be manufactured will be paramount. With that in mind,...

Im Focus: Exotic quantum states made from light: Physicists create optical “wells” for a super-photon

Physicists at the University of Bonn have managed to create optical hollows and more complex patterns into which the light of a Bose-Einstein condensate flows. The creation of such highly low-loss structures for light is a prerequisite for complex light circuits, such as for quantum information processing for a new generation of computers. The researchers are now presenting their results in the journal Nature Photonics.

Light particles (photons) occur as tiny, indivisible portions. Many thousands of these light portions can be merged to form a single super-photon if they are...

Im Focus: Circular RNA linked to brain function

For the first time, scientists have shown that circular RNA is linked to brain function. When a RNA molecule called Cdr1as was deleted from the genome of mice, the animals had problems filtering out unnecessary information – like patients suffering from neuropsychiatric disorders.

While hundreds of circular RNAs (circRNAs) are abundant in mammalian brains, one big question has remained unanswered: What are they actually good for? In the...

Im Focus: RAVAN CubeSat measures Earth's outgoing energy

An experimental small satellite has successfully collected and delivered data on a key measurement for predicting changes in Earth's climate.

The Radiometer Assessment using Vertically Aligned Nanotubes (RAVAN) CubeSat was launched into low-Earth orbit on Nov. 11, 2016, in order to test new...

Im Focus: Scientists shine new light on the “other high temperature superconductor”

A study led by scientists of the Max Planck Institute for the Structure and Dynamics of Matter (MPSD) at the Center for Free-Electron Laser Science in Hamburg presents evidence of the coexistence of superconductivity and “charge-density-waves” in compounds of the poorly-studied family of bismuthates. This observation opens up new perspectives for a deeper understanding of the phenomenon of high-temperature superconductivity, a topic which is at the core of condensed matter research since more than 30 years. The paper by Nicoletti et al has been published in the PNAS.

Since the beginning of the 20th century, superconductivity had been observed in some metals at temperatures only a few degrees above the absolute zero (minus...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Call for Papers – ICNFT 2018, 5th International Conference on New Forming Technology

16.08.2017 | Event News

Sustainability is the business model of tomorrow

04.08.2017 | Event News

Clash of Realities 2017: Registration now open. International Conference at TH Köln

26.07.2017 | Event News

 
Latest News

A Map of the Cell’s Power Station

18.08.2017 | Life Sciences

Engineering team images tiny quasicrystals as they form

18.08.2017 | Physics and Astronomy

Researchers printed graphene-like materials with inkjet

18.08.2017 | Materials Sciences

VideoLinks
B2B-VideoLinks
More VideoLinks >>>