DFS: Direct Finite Element Simulation


DFS is Direct Finite Element Simulation as best possible computational solution of Euler’s equations expressing first principle physics of slightly viscous flow (beyond drag crisis with Reynolds number larger than 500.000):

  • incompressibility,
  • momentum balance Newton’s 2nd law,
  • slip/small friction boundary condition on solid wall.

DFS with slip is parameter-free without need of turbulence and wall models and as such represents Einstein’s ideal model of physics.

DFS with small friction captures the drag crisis transition from no-slip to slip boundary condition at wall.

DFS is best possible as having a residual which a best combination of being small in a weak sense and not too large in a strong least square sense, in the presence of turbulence manifested by the fact that there is no solution with small strong residual.

DFS computes lift and drag of bluff bodies beyond drag crisis depending solely on form with very small contribution from skin friction. DFS solutions are partly turbulent.

DFS makes CFD as computational fluid mechanics computable with todays computer power.

DFS is implemented using FEniCS Unicorn.

Key Presentation of DFS: High-Lift III 2017

How to make CFD truly predictive: DFS


1 thought on “DFS: Direct Finite Element Simulation

  1. Pingback: Euler’s Dream Come True: DFS! | The Secret of Flight

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