2015 is here, but before we leave last year in the dust let's take a moment to review the 2014 blog posts that can make this year your best yet in Computational Fluid Dynamics (CFD).

External CFD Flow VolumeSubstance (air) modeled outside the car. Half model due to symmetry.

It's not just Google that can doodle. The Computational Fluid Dynamics (CFD) community on occasion has also been known to embrace its whimsy side, especially during holidays, and so I give you a CFD doodle. For fluid dynamicists (or at least this one) the snow globe has always had a special attraction and if one is good then four has to be awesome, right?

Multiple Interconnected Snow Globes Flow Animation

Given the adoption and success of modern GUIs across a broad range of software, you'd think that making the case for one would be redundant. However, for some reason Computational Fluid Dynamics (CFD) was a late adopter of GUIs, and for what is predominantly a visual set of disciplines - think geometry, mesh, solver feedback, 3D visualization, and 2D plots. This late adoption is still evident in CFD software today.

Modern CFD GUI: Caedium Professional

There are many reasons why Computational Fluid Dynamics (CFD) has become a mainstay of most engineering endeavors that have a fluid flow element, but here are my top 5.

CFD Software in Action: Caedium Professional

Niklas Wendel and Julia Gundert, students at Thomas-Morus-Gymnasium, Daun, Germany, recently completed a project to envisage an airliner of the future with a focus on sustainability and fuel efficiency. Their project was named HELT, translated as a German acronym for 'High Efficiency Aircraft', and is also similar to the German word 'held' which translates to 'hero' in English. During their early concept design phase they used Caedium Professional to perform Computational Fluid Dynamics (CFD) simulations to evaluate the aerodynamic efficiency of various configurations before selecting their final Blended Wing-Body (BWB) design.

HELT TeamNiklas Wendel and Julia Gundert

Just as Computational Fluid Dynamics (CFD) has found extensive use across a wide range of external flow applications, it is also used to simulate a diverse set of internal flow applications.

Wind Tunnel CFD SimulationStreamlines colored by velocity magnitude

Computational Fluid Dynamics (CFD) sees broad use in many applications across a diverse range of industries. No more so is this true than in the applications you'll see for CFD in external aerodynamics analysis.

CFD Simulation of a CityAir Velocity Vectors

You probably know that the Navier-Stokes (NS) equations are named after Claude-Louis Navier and George Gabriel Stokes. Navier come up with the first original derivation based on discrete molecular interactions (discrete approach) and Stokes originated the assumption of a continuum directly using viscosity that is the widely referenced approach still taught today. However, between these two approaches there were other derivations, a continuum of sorts, attributed to other luminaries of 19th Century science.

Navier (left) and StokesRoom for more?

Prior to Ludwig Prandtl (1875 - 1953), analytic analysis of fluids with an early form of Computational Fluid Dynamics (CFD), confined to paper and pencil, assumed ideal inviscid potential flow. However, this approach was less than ideal at predicting drag (d'Alembert's paradox) and airfoil stall, which was a pressing problem for engineers at the dawn of powered heavier-than-air flight. Prandtl developed practical theories for real fluids that found favor with aircraft designers. Also, like Osborne Reynolds before him, Prandtl had a non-dimensional number, the Prandtl Number, named after him.

The Life and Times of Ludwig PrandtlTold by Eberhard Bodenschatz

If you have performed simulations with industrial Computational Fluid Dynamics (CFD) and thereby solved the Reynolds-Averaged Navier-Stokes (RANS) equations, or if you have compared scaled fluid dynamic experiments with their full size counterparts using the Reynolds Number, then you have benefited from the groundbreaking work of Osborne Reynolds (1842 - 1912).

The Life and Times of Osborne ReynoldsTold by Brian Launder (himself a giant in turbulence modeling)