One Integral Read as 0.1406 and 56.91 — Torsion Stress Function and Duct Laminar Flow
·8 min read
A square bar's torsion constant and a square duct's f·Re are one Poisson solution read twice. One linear-triangle FEM run gives both handbook numbers.
How Far Must Water Flow Before It Becomes a Parabola — Entrance Length and Hagen–Poiseuille
·4 min read
The pipe entrance region, the Hagen–Poiseuille parabola, and the 64/Re friction factor