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The ascent of humanity

Navier–Stokes Equation

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What does it say?

It’s Newton’s second law of motion in disguise. The left-hand side is the acceleration of a small region of fluid. The right-hand side is the forces that act on it: pressure, stress, and internal body forces.

Why is that important?

It provides a really accurate way to calculate how fluids move. This is a key feature of innumerable scientific and technological problems.

What did it lead to?

Modern passenger jets, fast and quiet submarines, Formula 1 racing cars that stay on the track at high speeds, and medical advances on blood flow in veins and arteries. Computer methods for solving the equations, known as computational fluid dynamics (CFD), are widely used by engineers to improve technology in such areas.