Aerodynamicists reveal link between fish scales and aircraft drag — ScienceDaily

The team’s findings have been published in Nature: Scientific Reports: “Transition delay using biomimetic fish scale arrays,” and in the Journal of Experimental Biology: “Streak formation in flow over biomimetic fish scale arrays.”

Reducing drag means faster aircraft speeds and less fuel consumption — an important area of study for aerodynamicists such as Professor Bruecker, City’s Royal Academy of Engineering Research Chair in Nature-Inspired Sensing and Flow Control for Sustainable Transport, and City’s Sir Richard Oliver BAE Systems Chair for Aeronautical Engineering.

Through their biomimetic study, Professor Bruecker’s team has discovered that the fish-scale array produces a zig-zag motion of fluid in overlapping regions of the surface of the fish, which in turn causes periodic velocity modulation and a streaky flow that can eliminate Tollmien-Schlichting wave induced transition to reduce skin friction drag by more than 25 percent.

An examination of oil flow visualisation using computational fluid dynamics

Read More
Read More

Dow Falls Over 500 Points As Tech Stocks Drag Market Lower

Topline

The market fell sharply on Wednesday, adding to its sell-off so far in September as tech stocks again came under pressure and investors remained wary about a resurgence in coronavirus cases.

Key Facts

The Dow Jones Industrial Average closed down 1.9%, or 525 points, on Wednesday, while the S&P 500 fell 2.4% and the tech-heavy Nasdaq Composite dropped 3.0%.

Shares of Big Tech stocks, which have been the source of the sell-off in recent weeks, again dragged the market lower: Apple, Amazon, Microsoft, Netflix and Google-parent Alphabet all fell around 3% or more.

Tesla stock plunged over 9% after the company’s highly anticipated ‘Battery Day’, in which CEO Elon Musk detailed a new battery design that he says will make Tesla’s cars cheaper to produce. 

Some Tesla investors

Read More
Read More