2.0000 in laminar flow, 1.0322 in turbulent — the coefficient in front of the velocity head
·7 min read
A mean-velocity head is not the kinetic energy a pipe actually carries. Alpha is 2.0000 for laminar Poiseuille flow and 1.0322 at Re = 10^6.
Where Total Pressure Dropped 1,080 Pa, Dissipation Was Zero — When the Bernoulli Constant Crosses Streamlines
·8 min read
Inside a spinning vortex core the total pressure falls 1,080 Pa while viscous dissipation stays exactly zero. A Rankine vortex marks where a head deficit stops meaning loss.
Water Boils at 20°C Too — The Physics of Cavitation
·6 min read
At 20°C vapor pressure is 2.34 kPa. If a venturi throat drives static pressure under that line, water boils and the cavitation number turns negative.