Stability of Floating Bodies
For Equilibrium
1. The weight of the displaced water
must equal the weight of the entire
body
Fz FWeight FBuoyancy 0
2. The center of buoyancy and center of
gravity must act through the same
vertical line
M 0
Stability of Floa

AOE 2204 Dr. W. L. Neu
Physical Oceanography
Physical Oceanography References (and sources of figures)
Less Mathematical:
Oceanography: A View of the Earth, Gross, M.G., Prentice-Hall, 1982
Essentials of Oceanography, Thurman, H.V., Prentice-Hall, 1996
Mo

Basic
Structural
Theory
Beams
Beams can resist:
Bending moments
Shear forces
Torsional moments (wont consider this here)
Bending
simply supported beam
M
top in compression
bottom in tension
Cut beam free-body diagram
exposes moment
Moment is actually a

Strain
The deflection of a beam also depends on the material it is made of. We need to know
how much the material will deform for a given load.
Define Strain (normal strain)
Apply a load P to a rod of length L and cross-sectional area A. The rod elongates

Flow Measurement in Pipes and
Ducts
Course No: M03-011
Credit: 3 PDH
Harlan H. Bengtson, PhD, P.E.
Continuing Education and Development, Inc.
9 Greyridge Farm Court
Stony Point, NY 10980
P: (877) 322-5800
F: (877) 322-4774
info@cedengineering.com
Flow Mea

Stress & Strain
In the last section, we saw that the deflection of a beam depends on the moment of
inertial of its cross-section, I. The deflection of a beam also depends on the material it is
made of. We need to know how much the material will deform for

Ship
Structures
Loads
Pressure from water on hull (including waves)
Cargo
Structural weight
We are treating the ship as a beam
Benford
Example 1
A box-shaped barge 50 m long, I0 m wide and 5 m deep is divided into five equal cargo
holds (each I0 m long).

AOE 2204 Dr. W. L. Neu
Hydrodynamics
Viscosity
Viscosity is the property of a fluid which gives rise to shear stress when the fluid moves.
Assume the fluid to be composed of layers moving relative to one another (this is called
laminar flow).
If one layer

AOE 2204 Dr. W. L. Neu
Stability of Floating Bodies
1. Body completely submerged
Consider a submarine,
In Equilibrium
Rolled
FB
B
G
FB
B
G
W
W
In equilibrium, the buoyancy force, FB, acting at B, is equal and opposite to the weight,
W, acting at the cente

Hull Form Coefficients
Block Coefficient (dimensionless)
=
CB
0.5 0.9
LBT
L = LWL or LBP
usually
1
Figures from Benford
Maximum Section Coefficient (dimensionless)
AX
=
C X (C
=
M)
BT
0.75 0.995
AM
(Midship Section Coefficient)
2
Prismatic Coefficient (

AOE 2204 Dr. W. L. Neu
Pressure and Forces in Static Fluids
Pressure variation
Consider an infinitesimal element with dimensions dx,dy,dz in equilibrium in a static
fluid. Pressure, p, acts inward on all faces of the element. The element has weight dW.
Th