Wall or bank effect

Bernoulli’s law and continuity law

In order to understand the effect of a solid bank or wall on the behavior of moving ships along it, it is necessary to study pressure distribution around ship's hull and relevant basic laws governing flow phenomena.


Continuity law: Velocity x cross section = const

V1 x S1 = V2 x S2 = const.

Consequence: if cross-section decreases, velocity increases and vice versa

Bernoulli’s law: static pressure + dynamic pressure = const.

Static pressure = atmospheric pressure + head of water

Dynamic pressure = C x velocity squared

Consequence: if velocity increases, dynamic pressure increases, and static pressure and head of water decreases and vice versa.