Resistance & Propulsion (1)
MAR 2010
.Open water propeller tests, Standard
series model propeller tests and Propeller
design diagrams.
Rod Sampson - School of Marine Science and Technology - 21st February 2008
Open water propeller test
O/W tests performed
Analysis of Flow around a Ship Propeller
using OpenFOAM
Eamonn Colley
Supervised by Dr Tim Gourlay
October 2012
Honours Dissertation
Curtin University
Perth, Western Australia
1|Page
Abstract
This dissertation analyses a propeller based off the coordinate
Politechnika Gdaska
WYDZIA OCEANOTECHNIKI
I OKRTOWNICTWA
Thesis:
Parametric B-Wagenigen screw model.
Verify compliance CFD computation with
hydrodynamics plots.
Performed : Andrzej Rachwalik
Gdask 18.02.2013
1
I want to thanks for:
Cd-Adapco for sparing S
the International Journal
on Marine Navigation
http:/www.transnav.eu
Volume 8
Number 3
and Safety of Sea Transportation
September 2014
DOI:10.12716/1001.08.03.16
Drag and Torque on Locked Screw Propeller
T.Tabaczek
WrocawUniversityofTechnology,Wrocaw,Pola
Introduction to Computational Fluid Dynamics
Instructor: Dmitri Kuzmin
Institute of Applied Mathematics
University of Dortmund
[email protected]
http:/www.featflow.de
Fluid (gas and liquid) ows are governed by partial dierential equations which
Analysis of numerical dissipation and dispersion
Modied equation method: the exact solution of the discretized equations
satises a PDE which is generally dierent from the one to be solved
Original PDE
u
+ Lu = 0
t
Modied equation
Aun+1 = Bun
u
2p+1 u
2p
Properties of numerical methods
The following criteria are crucial to the performance of a numerical algorithm:
1. Consistency
The discretization of a PDE should become exact as the
mesh size tends to zero (truncation error should vanish)
2. Stability
Num
Time-stepping techniques
Unsteady ows are parabolic in time
use time-stepping methods to
advance transient solutions step-by-step or to compute stationary solutions
time
future
Initial-boundary value problem
zone of influence
present
past
u = u(x, t)
doma
Galerkin nite element method
Boundary value problem
Lu = f
u=g
0
n u = g1
n u + u = g
2
weighted residual formulation
in
partial dierential equation
on 0
Dirichlet boundary condition
on 1
Neumann boundary condition
on 2
Robin boundary condition
1. Mu
Finite element method
Origins: structural mechanics, calculus of variations for elliptic BVPs
Boundary value problem
Lu = f
in
u=g
on 0
0
n u = g1
on 1
n u + u = g on
2
2
Minimization problem
?
Given a functional J : V R
nd u V such that
J(u) J(w),
Finite volume method
The nite volume method is based on (I)
rather than (D). The integral conservation
law is enforced for small control volumes
dened by the computational mesh:
Integral conservation law (I)
Z
Z
Z
f n dS =
q dV
u dV +
t V
S
V
S
N
V =
V
Vi
Finite dierence method
Principle: derivatives in the partial dierential equation are approximated
by linear combinations of function values at the grid points
1D:
= (0, X),
grid points
ui u(xi ),
xi = ix
i = 0, 1, . . . , N
mesh size
x =
X
N
Firs
Dimensionless form of equations
Motivation: sometimes equations are normalized in order to
facilitate the scale-up of obtained results to real ow conditions
avoid round-o due to manipulations with large/small numbers
assess the relative importance of t
Getting started: CFD notation
2
p
PDE of p-th order
u
u
u
u
f u, x, t, x1 , . . . , xn , u , x1 x2 , . . . , p = 0
t
t
scalar unknowns
u = u(x, t),
vector unknowns
v = v(x, t),
Nabla operator
= i x + j y + k z
u =
i u
x
v =
+
j u
y
+
k u
z
=
x Rn , t R,
PROPELLER DESIGN
AND CAVITATION
Prof. Dr. S. Beji
1
Introduction
Propuslion: Propulsion is the act or an instance of driving or
pushing forward of a body, i.e. ship, by a propeller (in our
case a screw propeller).
Propusion systems: There are many types
4. PROPELLER THEORIES
a) Momentum Theory
It was originally intended to provide an analytical means for evaluating ship
propellers (Rankine 1865 & Froude 1885). Momentum Theory is also well known as
Disk Actuator Theory. Momentum Theory assumes that
the fl
3. HYDRODYNAMIC CHARACTERISTICS OF
PROPELLERS
The performance characteristics of a propeller can be divided into two groups; open
water and behind hull properties.
a) Open Water Characteristics
The forces and moments produced by the propeller are expresse
ITTC Recommended
Procedures and Guidelines
Model Manufacture, Propeller Models
Terminology and Nomenclature for
Propeller Geometry
7.5 01
02 01
Page 1 of 19
Effective Date
1999
Revision
00
Table of Contents
1
PURPOSE.2
2
ITTC DICTIONARY OF SHIP
HYDRODYNAM