Richard Smith's blog

Ketchup with your CFD?

If you are a ketchup manufacturer then maintaining your ketchup at the right consistency is a primary concern - same goes for ketchup connoisseurs. A new procedure developed by Bandulasena, et al at the University of Sheffield combines a simple experimental observation and Computational Fluid Dynamics (CFD) to characterize the viscosity of a non-Newtonian fluid, such as ketchup, so we can be confident that our ketchup will flow.

Caedium Free Surface CFD Simulation for a Non-Newtonian FluidCaedium Free Surface CFD Simulation for a Non-Newtonian Fluid

Dam Break CFD Simulation

Can't get enough of Caedium's free surface simulations? Then this new post is for you. This animation shows a transient CFD simulation of a dam break over an obstacle. The simulation is performed in pseudo 2D, i.e., it is one cell thick.

Free Surface Tank Filling CFD Simulation

This animation, created by Caedium Professional, shows a transient multiphase CFD simulation of water filling a tank that is initially filled with air. The free surface is shown as blue for the air-side surface and red for the water-side surface. Each frame of the animation was automatically rendered by POV-Ray (a ray-tracer) through Caedium.


CFD and a Human Powered Centrifuge

Exercise is a crucial ingredient for astronauts to maintain some semblance of their physiological well being and if you can combine that with exposure to artificial gravity then all the better. Enter the Human Powered Centrifuge (HPC), possibly destined for the International Space Station (ISS). It's an un-stationary bicycle that when pedaled spins around generating artificial gravity. Problem solved, right? Not so fast - nothing in space is that easy. When exercising, astronauts generate up to two times more carbon dioxide (CO2) than when relaxing and that level of CO2 could potentially cause problems for the sensitive ISS life support system. What to do? CFD to the rescue.

Super Cavitation Watercraft

Say you've been tasked with designing a new water pleasure craft optimized for speed called the Slickjet (fictional name). You ask the fundamental question - how do you travel fast through water? Easy, get as much of your Slickjet out of the water as you can. You know that the drag force acting on a totally submerged shape in water will be about 1000 times higher than for the same shape in air - the drag force scales according to the density of the fluid and water is 1000 times denser than air. Of course this assumes you are willing to get FAA approval for an aircraft rather than a boat. However, there is an alternative in that if you can somehow cocoon parts of your Slickjet in an air bubble as it moves through the water then you can convince the physics that those parts of your Slickjet are moving through air rather than water. This process is known as super cavitation and results in the drag forces acting on those parts of your Slickjet being more like those encountered in air rather than water.

GHOST Super Cavitation WatercraftGHOST Super Cavitation WatercraftCourtesy of Juliet Marine Systems

London 2012 Olympics: Fluid Technology for Cycling

Cycling is one of the fastest sports in the Olympics. With that speed comes an increased importance on aerodynamics. In cycling the aerodynamic design is focused on minimizing drag. However, as with swimming, there are carefully crafted rules that ensure there is only a narrow scope for aerodynamic optimization to gain a competitive advantage.

Fishing NetLondon 2012 Cycling Test EventCredit: London 2012

Vortex Shedding Behind a Cylinder

Given how simple the geometry defining a cylinder is, you'd intuitively think that the air flow around it would also be simple. And as with many things fluid you'd be wrong.

Vortex Shedding Caedium CFD SimulationVelocity vectors (high definition video)

London 2012 Olympics: Fluid Technology for Track and Field (Athletics)

A big draw of any Olympics is the track and field (athletics) events and no less so in London. What effect is the application of fluid technology to these events likely to have? If past Olympics are anything to go by - not much!

Nike Pro Turbospeed Promo Video: Starts at 0:50

London 2012 Olympics: Fluid Technology for Swimming

With the London 2012 Olympics just around the corner, I thought it would be interesting to review the application of fluid technology to various Olympic sports, starting with swimming.

Men's 200m Freestyle Final - World's Swimming Championship Shanghai 2011No more supersuits

Wind Turbine Crossed with a Blimp

Another helium-filled post - this time it's a helium-filled blimp that houses a horizontal-axis wind turbine [source: gizmag]. Altaeros Energies recently released a video of their prototype Airborne Wind Turbine in action:

Syndicate content