New research into drag reduction has the potential to help industries such shipping to reduce energy use and carbon emissions.
Professor
Derek Chan from the University of Melbourne’s Department of Mathematics
and Statistics said the research demonstrates a new way to minimise
drag of fast moving projectiles in water.
A
collaboration between the University of Melbourne and the King Abdulla
University of Science and Technology in Saudi Arabia, the research was
based on the 255 year-old Leidenfrost effect.
The
Leidenfrost effect describes the phenomenon where a liquid produces an
insulating vapour layer when it comes in contact with a solid surface
that is hotter than its boiling point.
The
new research used high-speed video footage to assess the drag produced
from polished balls dropped into liquid. The results found that the drag
on the ball is reduced to almost the minimum possible through the
creating of an insulating vapour as it falls through the liquid.
Professor
Chan said that the new drag reduction method has the potential to
reduce energy costs for a broad range of applications, such as ocean
transport and high-pressure pumping of liquid through pipelines.
“An obvious area of application is shipping,” he said.
“Australia
transports a large amount of products such as iron ore and grain around
the world. The ship’s hot body could substantially minimise the amount
of drag as it passes through water, therefore potentially reducing
transportation costs and greenhouse gas emissions.”
“There
are still a number of issues that need to be addressed before this drag
reduction method can be applied commercially, such as the effect of
increased heat on issues such as corrosion,” he said.
The
paper was published as a research highlight in Nature Physics today,
and in full by the Physical Review Letters, a peer-reviewed scientific
journal published by the American Physical Society.
The
University of Melbourne and the King Abdullah University are now
writing a follow-up theory paper. While the first paper demonstrated
that the drag reduction method is real and achievable, the follow-up
paper will provide detailed theoretical analysis of the research.
SOURCE: University of Melbourne
