Celebrating the physics of all that flows with Nicole Sharp, Ph.D.
- Profile
Beach Cusps
Beach cusps are arc-like patterns of sediment that appear on shorelines around the world. Cusps consist of horns, made up of coarse materials, connected by a curved embayment that contains finer particles. They are regular and periodic in their spacing and usually only a few meters across. A couple of theories exist as to how…
The Reynolds Number Illustrated
The dimensionless Reynolds number is a key concept in fluid dynamics, allowing scientists to distinguish regimes of flow between differing geometries and even different fluids. This video gives a great primer on the subject by examining the physics of swimming for a sperm versus a sperm whale. The Reynolds number is essentially a ratio between…
Reader Question: Oceans Meeting?
Reader favoringfire asks: Hi! Maybe you can help me: I’ve seen a pic revolving around Tumblr from the Danish city of Skagen showing the Baltic and North sea meeting. Where they meet the ocean is two very distinct hues of blue–what captions say are “two opposing tides with different densities.” Tides? Currents w/different temps often…
Bouncing Atop a Pool
When slowed down, everyday occurrences, like a drop of water falling into a pool, can look absolutely extraordinary. When a falling drop has low momentum, it doesn’t simply disappear into the puddle. It sits on the surface, separated from the main pool by a very thin layer of air. Given time, the air drains away…
Fluids Round-up – 21 September 2013
First off, I’d like to give a special shout-out to FYFD’s friends at Pointwise, who were kind enough to invite me for a visit this week. For any readers looking for CFD grid-generation software, check them out; they are a fantastic bunch and very good at what they do. My thanks again to everyone who donated this…
Other Ig Nobel Fluids
To round out our series on fluid dynamics in the Ig Nobel Prizes (which are not the same thing as the actual Nobel Prizes), here are some of the other winners. Last year Mayer and Krechetnikov won for a study on coffee sloshing when people walk. We’ve mentioned the pitch-drop experiment measuring the viscosity of an extremely viscous…
Ig Nobel Fluids: Shower Curtain Science
Nearly everyone has faced the frustration of a shower curtain billowing inwards to stick to one’s leg. Various explanations have been offered to explain the effect, but David Schmidt won the 2001 Ig Nobel Prize in Physics for a numerical simulation suggesting that the spray of droplets from the shower head drives a horizontal vortex whose…
Ig Nobel Fluids: Swimming in Syrup
Does a person swim faster in water or syrup? One expects the more viscous syrup would offer a swimmer greater resistance, but, at the same time, it could also provide more to push against. Gettelfinger and Cussler put this to a test experimentally with competitive and recreational swimmers in a pool of water and in…
Thank You!
I have the best readers in the world. Seriously, everyone one of you is amazing. In less than 23 hours, you have blown past the goal I set. I will be going to the APS Division of Fluid Dynamics meeting thanks to you. THANK YOU! For those of you reading who will be at APS,…
Ig Nobel Fluids: Cookie Dunking
Back in 1999 Len Fisher earned an Ig Nobel Prize in Physics for explaining the physics of dunking a biscuit or cookie in a liquid. The cookie is porous, with many tiny, interconnecting channels run throughout it. When dipped in a liquid, capillary action pulls the fluid up into these channels against the force of…