The Mesh Connects Us to a Wiggly World

The natural world is a wiggly place. Wood grain, shoreline, mountain range and sand dune - not a straight line in evidence.?

Alan Watts, a writer and philosopher with a passion for Eastern religions (as well as a self-proclaimed “spiritual entertainer”) considers human beings to be the curlicues at the end of the Big Bang. We each are a continuation of the universe’s big wiggle.

Despite being part of it, wiggliness is difficult for humans to understand. Albert A. Bartlett famously said “The greatest shortcoming of the human race is our inability to understand the exponential function.”?

And then there’s the most challenging wiggle of fluid dynamics: turbulence. None other than Richard Feynman called it the most important unsolved problem of classical physics.

So perhaps we compensate by creating a world dominated by straight lines and right angles. All you have to do is look at architecture.?

Grasping Wiggliness

Watts rhetorically asked how we get a handle on a fish, a wiggly thing for certain in addition to being slimy and generally difficult to grasp. As we all know, we use a net to catch a fish.?

The net is a nice regular object with so many squares in one direction and so many squares in another. So when we look at the fish captured in the net we see it virtually cut up into unwiggly bits that we can easily identify and quantify. The net is how we grasp and comprehend wiggliness.

The Mesh as Net

So if you read enough about Buddhism, you will find a CFD mesh generation analogy. The mesh (the net) is our framework for reducing the wiggly world of fluid flow to bits (in the computer) that bring us comprehension.

Importantly, when the fish is caught, the net is forgotten. Otherwise we risk the net becoming a veil that obscures truth.?

So the next time you generate a mesh for CFD, think of the wiggliness of the fish you’re trying to catch and use a net and beware the veil.

If you're interested in reading Watts' version of this story, it's here.