Number：

01100010

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Name：

呂明芳

Titles：

Associate professor

Author：

Hsing-Juin Lee, Shu-Wei Wang, Ming-Fang Lu and Jiunu-Shean Chiang

Paper name：

The Life and Death of Euler, Bernoulli, Navier-Stokes Equations and Associated CFD for So-called Incompressible Fluid Flow

Name of activity：

International Journal of Mechanical Engineering Education Vol.37,n3

Keywords：Incompressible Flow, FD/CFD, Impact Energy Loss, Historical Concept Revolution, Searching/Curing Fatal Derivation Error

Abstract：Euler equations derived in 1755 are the basis for general fluid dynamics analysis. Despite their sparking beauty, elegance, and sacrosanctity, it is well-known that fluid dynamics is a weird academic area full of paradoxes and disaster solutions, for which, viscosity is often only playing the scapegoat for answering many absurdities [1,2]. In fact, the chastity of Euler and sibling N-S equations has long been contaminated by babysitting them with artificial viscosity, upwinding and other measures in CFD. Although derived by momentum equations due to incapability to accommodate any cases with energy loss. Then, should we blindly keep worshipping these non-genuine momentum equations forever ? Insightfully, herein we find that thelong-lived slippery culprit for this fatal non-genuineness is a seemingly innocent“artifical”equalization of crosswise and streamwise fluid pressures by unawares disregarding any possible energy loss in deriving Euler equations. Although this is a concept-revolution paper with tremendous and panoramic impact on past/future FD/CFD academia, yet its back-to-nature surgery for curing the fatal eulerian error and associated judicious discussion on solution existence/uniqueness are not difficult to understand.

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