OCE515 : Marine Hydrodynamics
Stephan T. Grilli
Distinguished Professor
Department of Ocean Engineering
University of Rhode Island
Narragansett Bay Campus
Narragansett, RI 02882, USA
tel. : (401) 874-6636
fax. : (401) 874-6837
http ://www.oce.uri.edu/~grilli
email : grilli@oce.uri.edu
Synopsis :
This course deals with Marine Hydrodynamics , i.e., fluid
mechanics in the context of ocean sciences and engineering. Marine
Hydrodynamics studies the motion of water in a marine/ocean environment,
both in natural conditions (i.e., with free surface and bottom boundaries,
shore, waves,...), and possibly containing man-made underwater or floating
structures (i.e., ships, vessels, submarines, offshore structures,
pipelines,...).
The emphasis here, however, is on the fluid side.Natural
boundaries or structures are considered as obstacles to or generators of
fluid motion and hydrodynamic pressure is created and applied to the
structures as a reaction to this motion.
Prerequisites :
(i) undergraduate Fluid Dynamics course (MCE354 or equivalent)
or graduate fluid course (OCE510 or OCE514); and (ii) ocean wave course
(OCE307, OCE514 or equivalent) or permission of instructor.
Required textbooks :
Kundu, P.K. (1990) Fluid Mechanics. Academic Press, Inc.
Newman, J.N. (1989) Marine Hydrodynamics. The MIT Press, Cambridge,
MA.
Content :
The first part of the course deals with both the introduction
of fundamental hydrodynamics topics.
The second part then adresses specialized topics.
Adjustments to this list of content may be made depending on student's
backgrounds and interests.
Part I : introduction to fundamental
hydrodynamics topics
- Introduction :
Definition of a fluid, tensor/indicial
and vector notations.
- Motion of a viscous fluid :
Fluid properties. Flow kinematics. Strain and rotation. Forces in a fluid
and stress tensor. Equations of mass and momentum conservation. Constitutive
equation. Navier-Stokes and Euler equations for Newtonian fluids. Body
forces. Boundary conditions. Elementary exact solutions for simple steady
and unsteady flows (Couette, Poiseuille,...).
- Motion of an inviscid fluid :
Vorticity distribution. Vorticity dynamics. Bernoulli theorem. Kelvin's
theorem.
- Irrotational motion of an ideal fluid :
Governing equations and boundary conditions. Velocity potential. Stream
function. Simple three-dimensional potential flows. Two-dimensional potential
flows. Complex potential. Conformal Mapping.
- Brief introduction to linear water waves :
Linearized free surface boundary conditions. Plane progressive wave. Finite
depth effects. Superposition of waves.
Part II : applications of fluid
mechanics in the marine hydroynamics context
- Moving body in an unbounded fluid :
Pressure force. Added mass. Body mass force. Non-uniform stream.
- Floating body dynamics :
Linearized equations of motion. Harmonic body motion in regular waves (diffraction-radiation).
Hydrostatics. Added mass and damping. Wave exciting force and moment. Representation
of velocity potential (eigenfunctions). Scattering by a vertical cylinder.
- Marine boundary layers :
Laminar Boundary Layers in relation to drag forces.
- Effects of earth's rotation on fluid motion
- Introduction to model testing :
Experimental and physical evidence for fluid and body motion. Model testing
and dimensional analysis for : water waves, wave forces on stationary bodies
and body motions in waves. Steady and unsteady drag forces on plates, spheres,
slender and general bodies, ship hulls...
Adjustments to this list of content of Part II will be made depending
on student's backgrounds and interests.