427 | April 1983
SCHRIFTENREIHE SCHIFFBAU
K. Eggers und S.D. Sharma
Festkolloquium zur Emeritierung von Karl Wieghardt
Festkolloquium zur Emeritierung von Karl Wieghardt K. Eggers, S.D.Sharma , Hamburg, Technische Universität Hamburg-Harburg, 1983
© Technische Universität Hamburg-Harburg Schriftenreihe Schiffbau Schwarzenbergstraße 95c D-21073 Hamburg http://www.tuhh.de/vss
INSTITUT
FÜR SCHIFFBAU Bericht
Festkolloquium
DER UNIVERSITÄT Nr. 427
zur Emeritierung
von Karl Wieghardt
K. Eggers S.D. Sharma
Hamburg,
HAMBURG
April
1983
VORWORT Am 31. März 1982 wurde Professor Karl Wieghardt emeritiert, nachdem er an unserem Institut fast über die ganze Zeit seit der Gründung im Jahre 1952 gewirkt hatte. Aus diesem Anlaß wurde ein Festkolloquium durchgeführt, bei dem ein großer Kreis von Freunden und ehemaligen Schülern versammelt war. Wir hatten acht Kollegen aus aller Welt zu Vorträgen über Themen aus dem Bereich der maritimen Hydrodynamik eingeladen. Dabei war aber vorerst nicht an eine gemeinsame Veröffentlichung der Reihe dieser Beiträge gedacht. Da jedoch vier Vorträge bereits in Manuskriptform vorlagen, folgten wir einem mehrfach geäußerten spontanen Wunsch, die Arbeiten in gedruckter Form zu sammeln. Die restlichen Arbeiten werden anderwärts erscheinen, soweit sie sich in der vorliegenden Form für eine Veröffentlichung eignen. So sind die theoretischen Ausführungen von Professor T.Y. Wu über lange Wellen auf flachem Wasser, für welche sich überraschend Zusammenhänge mit dem Bericht von Professor J.V. Wehausen über experimentelle Untersuchungen aufzeigten, inzwischen in erweiterter Form auf dem 14ten Symposium on Naval Hydrodynamics in Ann Arbor vorgetragen worden und werden in den dortigen Proceedings zu finden sein. Andererseits konnte die nicht nur optisch sehr farbige Darstellung von Professor J.N. Newman über seine Durchsegelung des Nordatlantiks aus drucktechnischen Gründen nicht einbezogen werden. Hamburg,
im März
1983
Die Herausgeber
PREFACE Professor Karl Wieghardt retired from office on March 31st, 1982 after nearly thirty years of service in our Institute starting soon after its inauguration in 1952. To celebrate this event an "informal" colloquium had been organized, which was attended by a large number of his friends and former students. Eight colleagues from all over the world followed our invitation and contributed lectures on various topics within the broad field of marine hydrodynamics. We had not originally intended to publish formal proceedings, but the ready availability of four manuscripts has encouraged us to meet the spontaneous desire of several participants to study the material in writing. The remaining lectures will either appear in print elsewhere or are, unfortunately, not amenable to adequate reproduction on paper. Thus the theoretical exposition of Professor T.Y. Wu on long waves in shallow water, which incidentally turned out to be closely complementary to the experimental investigations reported by Professor J.V. Wehausen, has been subsequently presented in extended form at the 14th ONR Symposium on Naval Hydrodynamics at Ann Arbor in August '82and will appear in due course in its Proceedings. On the other hand, Professor J.N. Newman's colorful slide-show on his sailing cruise across the North Atlantic had to be omitted for purely graphical reasons. Hamburg March,
1983
The Editors
2
Festkolloquium anläßlich der Emeritierung von
Professor
Dr. rer. nato Karl
Wieghardt
am Montag, dem 29. März 1982, im Institut
für Schiffbau
Pro
-
9.00
9.30 h
der Universität
Hamburg
9 r a mm
Ansprachen
Prof. Hansjörg Petershagen, Direktor des Instituts für Schiffbau Prof. Hansjörg Sinn, Senator für Wissenschaft und Forschung Dr. Peter Fischer-Appelt, Präsident der Universität Hamburg
-
9.30 UDer
12.30 h
die
Prof.
Vorträge
inkompressible
Klaus Oswatitsch,
(Vorsitz:
Prof.
Potentialströmung
Technische
Klaus Eggers) im Staupunkt
Universität
spitzer
Körper
Wien
Ships in Very Shallow Water
Prof.
John V. Wehausen, University
of California,
Berkeley
Kaffeepause The Science
Prof.
Nonlinear
Prof.
and Art
of Wave
Klaus Hasselmann, Long
Forecasting
Max-Planck-Institut
für Meteorologie,
Hamburg
Waves
Theodore Y. Wu, California
Institute
of Technology,
Pasadena
Imbiß im Institut 14.00
- 17.00
Calculation
Dr. Eiichi Design
h
Vorträge
of Ship
Frictional
Baba, Mitsubishi
of Devices
(Vorsitz:
Dr. Som D. Sharma)
Resistance
Increase
Heavy Industries
for Improving
due
Ltd.,
the Wake Flow
into
Dr. George E. Gadd, National Maritime Institute,
to Surface
Roughness
Nagasaki the Propeller
Plane
Feltham
Kaffeepause On the Characterization
of Complex
Flows
Dr. Jürgen Kux, Universität
Hamburg
A Sailing
Atlantic
Prof.
View of the North
J. Nicholas
Newrnan, Massachusetts
Institute
of Technology,
Cambridge
3 Begrüßung
durch
den Direktor
Herrn
Prof.
Meine
sehr verehrten
Petershagen
Zum Kolloquium Dr. rer. nato Institut
Damen,
aus Anlaß
verhindert;
ich darf
lich begrüßen, trotz
Ihnen,
immer
Herren
Senator
Staatsrat
begrüße
sehr knappen
auch über den heutigen
deuten.
Mein
heutigen
Interesses
besonderer
Tages.
Veranstaltung, Ihren
und so danke
Beitrag
Erlauben
zur Gestaltung
Sie mir nun einige
gemacht
Anlaß
an der Arbeit
Gruß gilt auch Anlaß
herz-
hier
zu uns zu sprechen.
am besten
unseres
als
Instituts des
Kolloquium
ist sicher-
entsprechende
Art der
ich vor allem dieses
hinaus
den Vortragenden
Ein wissenschaftliches
lich die dem heutigen
ist
Dr. Fischer-
Terminplanes
Ich darf
Ihres
Bilstein
daß Sie es möglich
Begrüßungsworte
ein Zeichen
Sinn
ich Herrn
zu sein und einige dies wohl
von Professor
ich Sie in unserem Herr
aber Herrn
und ebenfalls Ihres
darf
begrüßen.
und ich danke
haben,
meine
der Emeritierung
Karl Wieghardt
sehr herzlich
Appelt,
des Instituts,
auch
Ihnen
für
Tages.
Grußworte
an unsere
ausländischen
Gäste. I welcome
our foreign
lecturers. on this
I thank
special
guests
and especially
you for your
occasion
which
our foreign
readiness will
to present
surely
make
lectures
this colloquium
a success.
Bevor
ich nun das Wort weitergebe,
Anschluß Danach
an die Begrüßung wird
Kolloquiums Darf
ich nun
Herr Kollege
darf
eine kurze Eggers
ich sagen,
Pause
machen
die Leitung
daß wir im werden.
des eigentlichen
übernehmen. zunächst
Sie, Herr
Staatsrat
Bilstein,
bitten.
4 Ansprache
von Herrn
als Vertreter
des Präses
und Forschung,
Meine
Staatsrat
Prof.
sehr verehrten
lieber
Damen
Ihnen
und der Bürger
unserer
Vorredner
Senator
Dort
tagt wieder
Thema
Sinn,
unsere
ist schon
eines
republik
im Wissenschaftsrat Hamburg
heute
die letzte
bedauert drückt einen
sich darin
Wie wichtig
Ihres
lagen
vor
Jahre
aussetzungen In einer nische
Thema
ist,
sind,
für die
und daß soeben
wird.
Kolloquium
Der Präses sehr.
morgen
Das
von ihm
erhielt.
so habe
im Laufe
vergleichbaren
Die Anfänge
morgen
in einern Gebäude
am Berliner
ist, haben
der Geschichte
erfahren.
ich mir heute
30 Jahren
geschaffen
Hochschulbau
hautnah
mit den jetzigen
Universität
auch
Vorentscheidungen
eingeläutet
von diesem
sozusagen
der Ingenieurschule ziger
in Bonn
soweit
aber
die gerade
Interesse
Herr Wieghardt,
Instituts,
lassen,
einige
wurden,
ein funktionsgerechter
Instituts
wissen,
ein in der Bundes-
aus, daß ich noch heute
aus Bonn
Sie, verehrter dieses
Sie werden
dazu
in Bonn.
die sich mit dem
interessierendes
Tagen
Abwesenheit
Gremien,
daß dies
getroffen Runde
und Forschung,
sind, möglicherweise
von besonderem
seine
Anruf
der vielen
ungemein
und daß in den letzten
worden,
ist. Er ist zur Zeit
Kollegen,
Deutschland
des Senats
hingewiesen
für Wissenschaft
oder Deutsche
Stadt
darauf
beschäftigen.
ausländischen
Wünsche
Stadt.
verhindert
Hochschulbau
Sie Hamburger
und Herren,
sehr gern die besten
der Behörde
Herr
für Wissenschaft
!
Ich überbringe
daß der Präses
der Behörde
H. Sinn
Herr Wieghardt
Von meinem
Bilstein
noch
im Hinterhof
Tor, bis zu Beginn
Gebäuden
sagen
bessere
der sech-
räumliche
Vor-
wurden. Situation
Hamburg-Harburg,
ist zur Zeit noch zwar nicht
die Tech-
in einern Hinter-
5
hof, aber
doch
brauchbaren
Gebäude.
ich anmerken, wohl
dieser
Für unsere
die letzte
wenn
zu verringern
bzw.
die im Süden
neuen
in diesem Die Zielsetzung Hamburgs
Defizit,
aufweist,
In dem bisher
dieser
Universität
17 Professoren
mit ihren
Mitarbeitern,
wird
TU-eigene
Gebäude,
gebaut
das das
ganz Norddeutschland
zu beseitigen.
darf
Hamburg-Harburg
sein wird.
Gebäudekomplex das erste
Gäste
Universität
ist es, das naturwissenschaftliche wie allgemein
funktional
Hochschulneugründung
Universität,
Land Hamburg,
auch
ausländischen
in der Bundesrepublik
Technischen
wird,
angernieteten,
daß die Technische
vermutlich
Jahrhundert
in einem
angernieteten
arbeiten
bereits
und in wenigen
das Technikum,
Wochen
übergeben
werden. Meine
Damen
und Herren,
insbesondere
auch
technik - einen Forschungsschwerpunkt es in diesem Ich glaube,
Gebäude
weitere
das dürfte
für die Schiffs-
der TU Harburg
gute Arbeitsmöglichkeiten
für ein fachkundiges
gute Nachricht
sein.
Die bisherigen
Anfangserfolge
gen parallelen
zum Institut
dieser
neuen
räumliche
eine
Universität
zei-
für Schiffbau:
Mängel
-, wenn
geben.
Auditorium
Wenn
Engagement vorhanden ist, lassen sich Mängel insbesondere
wird
-
-
persönliches
ich meine
auch mit großer
Mühe,
überwinden. Meine
Damen
und Herren,
strukturelle
Defizit
pauschalität
gilt
gen Abteilungen Institut bisher aber
genauso
der Fachbereiche
bestand.
von Ihrem
gesprochen.
etwas
Institut
Neben
und Chemie
eini-
ist das
der Universität
weniger
als einem
der Mathematik
Gebiete
Bei dieser
technisch-naturwissen-
die im Rahmen
Fächer
wie verschiedene
zu machen.
Physik
die einzige
Man hat dabei
auf das bisherige hingewiesen.
es, Einschränkungen
Einrichtung,
treffend,
Gebieten
Norddeutschlands
für Schiffbau
schaftliche
ich habe kurz
der Physik
respektvoll,
Hamburg dafür
"Zoo" von vielen gehören
zu ihnen
neben
den klassi-
6
schen
ingenieurwissenschaftlichen
Was an Ihrem wird
Institut
bereits
Bereichen. vorhanden
mit der TU Hamburg-Harburg
erhalten:
Die Erfahrungen,
Einrichtung
wie die Ihre
Funktionieren arbeit
dieser
Hinweise
geben
tungen mehreren
anderen
Es wäre
schön
technischen
sammeln
wissenschaftliche
ausgerichtet
wenn
Doch wird
in Hannover diese
Lassen noch
einmal
meine
ein Wort
Dank
Stelle
wie Ihr
in diesen
Institut.
der Verträge
Tagen
eher äußerliche
entscheidend
mit
schiffs-
hätte
statt-
Terminsache
ist, für Hamburg dieser
Arbeitsbedingungen
wie
Bereiche
in
und -möglichkei-
läßt.
Sie mich,
richten.
Einrich-
lokal~sierten
daß die Konzentration
und bessere
wertvolle
die Unterzeichnung
wie geplant
Zusammen-
auf Zusammenarbeit
für Ihr Institut, ten erwarten
für das
Denn wenige
lassen;
gute
werden
wie für ihre
sich verschmerzen Hamburg
Ausweitung
in Hamburg
der b~sher
können.
konnte,
so ausgeprägt
ist,
so interdisziplinäre
Hochschule
Hochschulen
Bereiche
adäquate
Hochschulen
sind
gewesen,
zur Umsiedlung finden
können.
in Hamburg
die eine
neuen
mit den anderen
seine
und eingespielt
Damen
und Herren,
des Dankes
für die 30jährige
des Instituts,
bevor
ich schließe,
an Sie, Herr Wieghardt, Tätigkeit
an verantwortlicher
mit der Sie seit den Jahren
aufbaues
in Lehre,
Forschung
leistung
entscheidendes
des Wieder-
und wissenschaftlicher
zur jetzigen
Stellung
Dienst-
der Einrichtung
beigetragen haben - sei es im Rahmen der alten "math-natFakultät",
sei es in der formal
Selbständigkeit
der Jahre
der Dank besonders Berechnung, mich
geradezu
licher
mit ein, was
Konzeption
im U-Bahn-Bau,
seit
organisatorischen
1970. Für Hamburg Ihren
Beitrag
und Dimensionierung
vor allem prototypisch
Dienstleistung"
größeren
aber beim
betrifft
für die Gesellschaft
zur
bei der Belüftung
Elbtunnel.
für das, was mit
schließt
Das ist für "wissenschaftzu bezeichnen
ist. In zwei Jahren
wird
das traditionelle
Symposium
des
"Office
of Naval Research" in Hamburg stattfinden - sicher kein
7
alltägliches ner Anlaß, weiterhin tätig gesützt
Ereignis. Ihnen
Es ist für mich
für Ihre Bereitschaft
für die wissenschaftlichen
zu sein und ihre Belange auf Ihre Erfahrung,
Ich wünsche dazu allen
aber auch willkommezu danken,
Einrichtungen
in internationalen
auch in Hamburg Gremien,
zu vertreten.
Ihnen,
sehr geehrter
Herr Wieghardt,
Erfolg,
dem Symposium
einen
guten
persönlich
Verlauf!
8 Ansprache
von Herrn
Präsident
der Universität
Ladies
Hamburg
and Gentlemen
It is indeed you,
Dr. Fischer-Appelt,
a great
the great
at this
pleasure
family
of shipbuilders
fine Institute
It is very
early
of Naval
who had official
to attend
last night.
rather
early
for me to welcome
and naval
Architecture
in the morning
for those ning
and honour
this morning.
for everybody
business
and I am glad
and especially
or private
Nevertheless,
architects,
undertakings
you are used
to beg in-
to be with
you again
of Professor
Wieghardt
this
morning. This
is a colloquium
occasion
in honour
of his retirement.
Wieghardt
was born
in
in Vienna. But he was brought up in Dresden where his
1913
father You,
was appointed
Professor
engineering interest master
Professor
Wieghardt,
and advanced
in advanced
gen, where
you worked
your
tute you also World
international after
your
England
and Germany
offered
a position
at this
It was,
für Schiffbau
which
you finally
longer
the pressure encouraged
you
worker
in the
research
insti-
the Second Laboratory
I suppose,
a unique
so short
to bridge
time
the gap
In 1952 you were
at the Hamburg
accepted
you to come
on to Göttin-
After
this war.
and charm
special
Research
You helped
as an assistant
Your
of the Max-Planck-
habilitation.
after
mechanical
the famous
a research
for you especially War.
University.
In Göttingen
in the Admirality
World
later
Prandtl,
and became
experience
between
strongly
you
Professor
1949 to 1952.
the Second
resist
brought
a forerunner
completed
from
in that city.
the time you spent
War you worked
in England
to study
and flow research.
doctorate
During
began
physics
with
Kaiser-Wilhelm-Institut, Institut.
at the Technical
later
physics
of mechanics
completed
who
Professor
on the
after
you could
of Professor to Hamburg.
Institut no
Weinblum This decision
9
was certainly large
not an easy one for you.
laboratory
and exchanged
in those
days was a rather
But with
the aid and support
Foundation,
the Institut
became
known
throughout
the world.
in this
abroad,
is sufficient
Wieghardt,
you remained
were
respected
and became
Together
and your with
of Hamburg, founding and,
fathers
Architecture will
probably
the support
it will and will greater
institute.
University
a very
great
from Hannover
at the Technical
area
and be
by your
today
in your because topics future
as one of the have my support persons
future
work.
I believe related
and
to this
in Hamburg.
institutes
Naval
I say
Naval field
So when
join us and we establish
a solid basis
of Hamburg.
of the University
You will
University
be one of the major provide
example
themselves.
enjoy
of all responsible
and all the other
our colleagues institute
Wieghardt
to the future
have
among
your
be continued
as president
Professor
of this
looking
followed
but
pupils.
of the Hamburg
this also
not only
teacher
certainly
work will
in
the world,
and researchers
all of us here,
I thank
I think,
bodies
that your
several
here
You were
all over
pupils
But you must
Professor
universities,
Institute
of a good
teachers
You are now retired. colleagues
field
You,
and
in it. Although
for this.
some of your
institu-
of the leading fact.
of this
the reputation
And
similar
to you by other
in your
well-known
to know
share
member
Research
from this country
of this
you especially
enjoyed
students.
proud
today,
offered
by experts
among
The presence
evidence
a devoted
Harnburg. Thank you also
here
of mathematics
of Harnburg University
esteemed
have had a decisive
professorships
your
field
which
in a backyard.
and the German
für Schiffbau
and highly
experts
place
of the faculty
of this university
tions
it for an institute
desolate
and science well
You left a very
a new
of Harnburg-Harburg, of Naval
for cooperation Architecture
Architecture within
has a good
the tra-
10
dition
in Hamburg
Marine
research
and is matched
this
area
effort
mineralogy existing
that will
will
work
Research
of us all.
Areas
Our future
Vergnügen
Zwölf
Jahre,
auch
meinem
schon
in Hamburg
anläßlich in Ihrem
ein längerer.
verbunden
-
Ihrer
Leben
the already and 94 be
ein ganz großes mit einem
Hauch
ich werde dies nachher Emeritierung
überreiche.
gewirkt
ein kurzer
haben
will
!
zusammen
Jahre,
haben,
this
to the benefit
ein Abschied
die wir in Hamburg
sind vielleicht
projects
Herr Wieghardt,
von Trauer, daß ich Ihnen heute die Urkunde
Technology)
is in the sea
und ein wenig
tun
to establish with
In
and
and the Atmosphere),
promising
lieber
geology
together
(Marine
the Ocean
out very
Es ist für mich,
98
a new special Processes".
of geophysics,
area which,
between
to carry
"Oceanic
We hope
studies.
of our university,
to establish
be called
together.
research
(Interaction able
we are trying
the departments
new special
related
is one of the strongholds
and at the moment research
by other
haben,
Abschnitt,
die uns hier uns öfter
in
gemeinsam
zusammengeführt
in Ihrer Arbeit, zuweilen auch in meiner Arbeit - und am Ende in gemeinsamer Wissens
Arbeit,
und seiner
und im weiteren schaft.
die uns verbindet
Vermittlung
Sinne
Dieses
Stück
aller
das zu ihren
bedingungen
gehört,
sich angelegen
sein
der Schiffbauer, schönen
Faches
Ost und West, zu feiern, sondern möglich, bare
Stückchen
verbindet. aus Nord
weiß
Ich wünsche wohl
mit auch
Gesellja Lebens-
für Schiffbau
alle
große
so viele
Kollegen sind,
nur Sie allein
dies
zu danken
Ihnen Ihren
im Kreise
Ihrer
dieses aus um Sie
mit Stolz,
und, wenn
noch viele
Kollegen
stets
Familie
Institute
und Süd hier versammelt nicht
Studenten
nur unserer
Es ist eben eine
sicher
neuen
das die Universität
Institut
Daß heute
die Universität
Gelassenheit,
unserer
Bedingungen,
die rund um die Welt
der Zusammenarbeit
den Familie.
nicht
wesentlichen
lassen.
zurückzugeben.
Jahre
Bürger
hat dieses
das erfüllt
auch
zum besten
Internationalität,
verkörpert,
in Erkenntnis
frucht-
und ein so reizen-
11
Antwort
Meine
von Herrn
Damen
Prof.
Wieghardt
und Herren
"Zwei Seelen wohnen, ach, in meiner Brust". - Das kommt daher, schon
daß wir hatten,
entwickelte Jahre,
-
heute
als wir noch
sitzen
haben.
Reptilien
sich tumorartig
merkwürdigerweise
neocortex
mir
ja zwei Gehirne
waren.
erst vor einer
die ratio
und die Logik,
über Verdienst
Das neue Million
In diesem und die sagen
ganz deutlich, daß ich
-
geehrt
das wir
halben
nur beim Menschen.
als Schiffshydrodynamiker weit
Das alte,
werde,
um mehrere
Nummern
zu sehr. Andrerseits, zwar auch
im alten
die warmen
Gehirn,
und heißen
des Gedankens
Blässe
eitlem,
Männchen:
alten
Und in der Tat,
da hausen
den ich mir selber
Gefühle,
angekränkelt
sind.
Ist das nicht
es ist schöner hätte
danken.
ausdenken
Allen
ten für die freundschaftliche Jahre
lang,
jetzt
Institutsangehörige,
danke
ich den Veranstaltern
Rednern gekommen
bei manchen
und Freunden sind.
die nicht
wunderbar
-
30 Jahre
Wunschtraum,
Kolloquiums
und Studen-
über viele
lang.
Studenten.)
dieses
und Kollegen,
!
Ihnen allen nur
Zusammenarbeit nicht
von
können.
Institutsangehörigen
bis fast
und
Und die sagen mir
als der schönste
Deshalb kann ich - trotz aller Bedenken sehr herzlich
die Gefühle,
(Ich meine
Ebenso
warm
und allen
die von nah und fern
12 Die inkom ressible Strömun
am Stau unkt schlanker Sitzen
Klaus Oswatitsch
1. Einleitung
Die Untersuchung sei auf stationäre inkompressible Potentialströmung beschränkt. Bei den geläufigen Theorien für nicht angestellte schlanke Profile, Rotationsrümpfe oder Flügel wird mit Quellbelegungen der Körperachse oder Körpersymmetrie-Ebene gearbeitet. Die vereinfachten Randbedingungen führen dabei an Profil-, Körper- oder Flügelspitzen zu einem sprunghaften Beginn der Quellbelegung. Dieser hat jedoch eine logarithmische Singularität für die Geschwindigkeit an der Spitze zur Folge. Die Geschwindigkeit wird am Belegungsbeginn nicht Null sondern negativ logarithmisch unendlich, vgl. etwa [1J, S.443 und S.458. Dieser
Fehler
Körperspitze
beruht
sprunghaft
Strömungsrichtung auch nicht
gravierend
Stark
Flügelspitze kann
spitze
einer
als konstant
digkeitsbetrag Potenz
Während
des Abstandes
Theorie
an der Keilspitze,
einer
Strömung,
schlanker
dieses
die Umgebung
einer
Körper
Mangels
soll
auf Strahlen werden.
Diese
mit der reinen durch
Längen-
durch
die Kegel-
Eigenschaft
hat
aber auch der Geschwinkonstant
mit einer zu. Diese
also bei der ebenen
Sie ist keinesfalls
eines
oder
Uberschallströmung
die Spitze
Strömung
die man mittels
Körper-
In Ermangelung
von der Spitze
schon
Fehler
werden.
bei letzterer
auf Strahlen
der skizzierte
es doch unbefriedigend,
Die Begegnung
angenommen Strömung
an der
daß sich dort die
Wenn
so erscheint
Kegelspitze.
er bei inkompressibler
beherrscht.
ändert.
die Strömungsrichtung
gemeinsam.
nimmt
wird.
die Quellbelegung
sondern
bei einer
entspricht
die inkompressible noch
ist,
kurz dargelegt
vergrößert
maßes
beginnt,
selbst
wiedergegeben
im folgenden
daß nicht
sprunghaft
daß der Staupunkt falsch
darauf,
konformer
positiven
Eigenschaft Strömung
Abbildung
auf schlanke
ist,
Spitzen
tritt
zutage,
völlig beschränkt,
13
wird uns aber besonders zur Lösung unserer Aufgabe dienen.
2. Separationsansätze Die Geschwindigkeitskomponenten
seien
durch
ein Potential
dargestellt:
=
u wobei
v
~CI)
-c::
0
;1-
~l/') ~N
~N
'-' ..c::
('I") ~~m
~('I")
CO
N
('I")
~bO l/')
0
CI)
CI)
~..c:: ~,-... bO ~a Q)
Q)
~~. N ~~..c:: I.() Q)
J..4 ~Q) ~tJ (1) ........ .D cd ~
0
0
0
~0
o ~
........ cd ~ o 0"" ~ o 0"" f...4 tl..
L.f)
~~J..4
~tl..
f...4
§ ~ V) 0"" V) (1) f..4
°
~0 00 ~~~~0
Q')
X
cd
(1) o
0
r" Q')
~~~~~0
~
e
Q)
Q') 0
~J..4
~::s
CI)
J..4 ~Q)
~.Q
z
.--I
l/') .--I
69
UJ Q) ~ "M .-i S rd Q) ~ +J UJ .-i rd "M +J ~ Q) +J o P.. "d ~ rd ~ rd .-i P, :>1 "Ö o ~
70
~
s:: ..... ~
e
113 ~
s::
0
tU)
.~ +I
~
l
113 ~~~
s:: s:: 0
~~~ 113 ~ ~ s:: +I o 113 ~ +I 113~~ r-i 113
~
u
I
"
~
l
l
~
,
~
~
~
~
~
~ 44
~ ~ U)
~ tJI ~ 0 ~
113 U ~ +I 113
~ 0 44
P.
8.3+1
U)
'
~ 113 113 +I ~ U 113 ~
~ ~ +I
11
~
I
i
I
~
>. ~
'
Lf)
o
Lf)
I
M
0
.
Lf)
i
0
0.0
~
I
s::
\]
I
44
i
.
.
I
113
:
~
o
+J U ~ 44 44 ~ N
o 000 o q
N
o :;:: Q) oS:. ...
c: o
I
~a. Q)
~
't:::::J U)
GI u
-'-
i~
0
'"
(wti)
:.;
-'-
I 0
,
,
I
C>
C>
C>
~0
-:-
0
0
~'"
~461"4 ......u46noij (wri)
-'-
IV
V'\
I 0
..... ~-4 ..
...
V'\
I 0
~,.... ..
-'-
IV
~~~~V'\
'"GI
I 0
0
.-
I
I 0
0
0
-:-
0
0
~46"4 sSlu~6noij
0
0
~-4
0
0 ,....
,
,
, . ,
I
b
V'\ 0
0 N
(wri)
0
0
.-
I 0
I 0
.-0
0
I 0
r:-' ~46"4 SSiu46noij
I
I
I
~0
0
"1
I
0 0
~N (wril
I
0 .-
I
0
lo
. , . 0
I
0 0
i... ii ca Q) ~ o....
~r:-'
~461"4 SSlU46noij
"~ u..
-
77
-
. 5
3
2
o sUffle.
1
6 surflCl
2 )
o surfle.
o surf ICt .. 1
o
10 z so 5 u.ttlv Fig. 9 Measured mean velocity distributions at station 7 (on the floating element) for different free-stream velocities on rough surface no 3
78
CI) C o .rot -tJ
o C ':} ~
..
.... co G) C
GO
.c
VI)(
VI )(
DC:
~DC:
bO ::J
V
(:)
.
GO
VI
o
(\')
~
...
-.
1.1)
CD
GO
"
'" tJ 11 It-t
..
DC:
-tJ tI r-4
0 tI ....
&.
Cf)
~.
S. ::J
'" ~
,..
-1.1) ~(\') .
e
0
'" C
..
o 0, .rot C -tJ ~I p.UJ .rot tJ, ~ (J (J I '" COIt-t G) ~ 'O::J 4
"'.cb( (J .rot::J
~g 4
'" CO < .... '-'" ~ ~~ U) N ,...... .. ::> ....... P"'f CI) ...::I > '8 Ei tIO o Ei P"'f N '-' ....... V) . V) . P"'f o 11 .... ~ u
V) P"'f . 00 o
,...... ~ '-' ....... ,...... N '-'>< ,...... P"'f '-'
P"'f CI) 1 Ei
'5 0i 11I
,...... N '-'>< ,...... ,...... P"'f ..... '-' '-'
,...... ~ '-' ....... ,...... N '-'>< ,...... P"'4 '-'
\0. V) \0 o o . o
0\ . V) 0 0 0
,...... N '-'>< , ,...... P"'4 P"'4 '-' '-'
o o P"'4
\0 o P"'4
o V) N . o N o o P"'4
,...... ~ ....... ....... ,...... N ....... >< ,...... ..... .......
N ~ V) P"'4 o o
0\ 0\ N ..... o o
co .... N \0 ..... o o .... o
o N ~ P"'4 o o
~ ..... P"'4 o o
o V) .... I"P"'4 0\ o o o
. \0 o P"'f o o
V) 0\ 00 o o o
I"..... co o P"'4 co o o o
V) 0\ co o o o
oV) I"o o o
l"V) \0 o o o
....
,....... ~ ....... ....... ,....... N ....... >< ,....... ,...... N ....... >< ,...... ,...... ..... ....... .-......
.-......
81
e _
~
"',
"'-,
~
,,"'-. \
\D
'
"\,
\
".
'\
,
\
, I
-
,
\,.
'
.1
.I
/,
I.
I
I
l'
ft
'.=s t
~
:
I
.";
1/ I/ 1./I ; I/ I ' J.
I I I
:
g 000
1
,,"A ,Af~-
-:>
",.l! .At/'~
;~
.1"4
~~ 4)
cU~ +J c: 0 cU f-+J
J8 I
=
0
tIO ~
/ 0
.s:: 4)+J
U
~ (5
8'"
0
0U U
4)
i
'
N
.1"4
~ ~ ~~ 4)0
>
.
~
:
+J '1"4 cU UtlO;j
~
~ ::i
I
'
.~.
,., Ö
·
:
J
IQ 0
~;j
c:: 4)
.b-
i
~
~
4)
on
~ 0
..
I
1 I
ä:
i
\
\
\
4) U
N ...;
o
g-
.
t.r..
- 13
,;;; I.n ,0 1'"
4)
e
U
cU
I'~
a ,-
~ ~;j
=
+J ~ c:: 4)
C7' ~
· ..
':::
:~
0
~ .. !.
~0 ",8l!.Atl'~
::: 0 -13
ö0
0
I,.,
=
0 ....
.';!' u..
82
Design
of devices
for improving
into the propeller
the wake
flow
plane
G.E. Gadd
This paper
relates
if the boundary unsatisfactory occur
most
forms
as dealt
with
twin
or shaft
layer wake with
development perhaps, forms
brackets causing
annoyance
and discomfort
warships,
unacceptable
Ways
of avoiding
fatigue
design
regions
of unduly
Sometimes
however
would
be acceptable
is then necessary ships
attaching major
its manufacture
Such problems arise
shadows
ship however
from bossings
For both
types
damage
to the ship, with,
as well
involving
as
in the case of
noise.
vibration
excited
to ensure
vibration
is by
there
are no local
in the flow entering
the propeller
which
that
it had been
a eure.
In such cases
eure has often
fin above
of ship and
thought
turn out not to be so in practice,
a successful
structure
to an
screw merchant
of radiated
designs
to devise
a large
leads
flow can be vibration
propeller
low speed
may arise
They can also
excited
of the stern
disco
single
to the crew,
propeller
careful
plane.
if the wake wake
levels
which
the hull
are excessive.
The best way of avoiding
screw
with
of unsatisfactory
possibly
over
in this paper.
screw warship support
problems
in the propeller
commonly,
the result noise,
to the serious
been
the propeller.
considerable
and attachment
and it
for single
effected
by
This however
is a
cost and difficulty
in
to the hull.
Flow deflectors A much
cheaper
applicable
alternative
either
to single
method screw
of curing ships
the problem,
or to twin
screw
ships
83
with bossings, is to fit flow deflectors. In the two full scale cases with which the NMI has been concerned to date, /7/ these have been relatively small cambered aerofoils welded to the hull (fig. 13). In the first such case these deflectors made a considerable improvement and in the second they cured the problem completely. However the positioning of such deflectors is critical to their success, and in the cases just quoted this was only achieved after making initial full scale trials with less successful arrangements. There is therefore a need to devise reliable model technique for determining an optimum arrangement of flow deflectors before fitting these to the full scale ship. The present
describes
some experiments
(the most
successful)
case mentioned
to develop
a technique
such that
second hoped
predicted work
paper
from the results
on the full scale.
in any future arrangement the need
The stern
in the case
This made
it especially
arrangement such astern
boundary
layer
by Gadd's defrectors 5 and
method
flow speed
the
enabling
tended
difficult much
would be used
a successful
fig.
away
and avoiding
flow
deflectors
5 m waterline
to the bulbous
of
on the model
contours
calculated
of the flow deflectors.
situated
in the region
trailing
edges
be in a region
than on the ship, whereas
The
of the 3,
on station
to the calculations would
de-
tank models,
variations
to occur
type.
the best
towing
girthwise
14 shows wake
their
that according
scaled
on ordinary
are likely
with
on the model
could
to determine
larger
on the ship were
It can be seen tors near
considered
/1/ at the plane
7 m waterlines
have been
the same technique
tank tests with
Thus
It was
experimentation.
thickness
than on the ship.
it could
to the ship straight
by tests
for with
above.
to the
that the deflectors
may arise,
to be fitted
The reasons wh y towing are unreliable
flector
Then
case which
for full scale
obtained
relating
3/4.
the deflecof much
lower
there would
84
be much smaller differences for the 3 m and 7 m levels. Moreover at the 3 and 5 m waterlines the flow angles at the hull surface are predicted to be considerably different on the model from those on the ship, as can be seen from figs. 15 and 16. Thus the calculations suggest that the model scale flow deflectors at the 3 m and 5 m waterlines will behave differently from the full scale ones.
Experimental At least
confirmation
at the model
to be qualitatively
15, shows
the predicted
that these
ones.
to earlier
boundary
layer
Moreover
Thus
tank,
agree
same hull
quite tunnel
form,
on this model
ones,
appear
of a photograph
as indicated
one of the wind
measured
from the predicted
predictions
the tracing
directions
was of this
profiles
predictions
the theoretical
in the towing
referred dissimilar
scale
correct.
of flow directions in fig.
of theoretical
by tufts, well
with
models
and are not too
as can be seen from
fig.17.
Foreshortened models with correct afterbody shape The above discussion has shown that it is hardly surprising that difficulties were experienced in correctly predicting the full scale behaviour of flow deflectors from tests on exactly scaled models. It would clearly better to use a model which, whilst having the correct afterbody shape where the deflectors have to be fitted, was distorted upstream in such a way that the boundary layer flowing over the deflectors approximated more closely in its thickness and flow angles to that on the full scale ship. This led to the consideration of a distorted double model as shown in fig. 18. (It is shown here in its final test configuration in a cavitation tunnel, as discussed below.) Ideally, the flow in the propeller plane of such a model should resemble that on the ship, but the natural unmodified flow might not do this, so that corrective
85
devices might have to be attached to the model. Any such devices would have to be placed weIl forward of the flow deflectors which it was required to test.
Calculations to assess whether flow corrective devices are likely to be required To give a preliminary indication whether or not such corrective devices were likely to be needed, further calculations were made. Hull surface flow directions on the fore shortened model were predicted as in fig. 19 to be even more upwards at the plane of the flow deflectors than those on the full scale ship, suggesting that an artificial cross-flow in the boundary layer might need to be introduced. Propeller plane wakes were also calculated for comparison with those calculated for the undistorted model and ship. Such calculations are at best very crude, and as can be seen from fig. 20 they fail to predict the narrow but quite intense wake in the upper half of the propeller disc on the undistorted model. This narrowed wake can be associated with the streamwise vorticity generated by the bulbous stern, and although this in itself is predicted quite weIl (fig. 15), its effects on the wake are not. The prediction for the full scale case (fig. 21) appears to be even worse, though here we have only a scale-corrected wake with which to make comparison, and the validity of the correction procedure is perhaps open to question. Despite the inaccuracy of the predictions in figs. 20 and 21 however, the difference in character between these predicted wakes and that predicted for the foreshortened model in fig. 22 is sufficiently marked to reinforce the suggestion that corrective devices are necessary for the latter model. The comparative lack of streamwise vorticity in the afterbody flow has led to a wake which is wider at the top and narrower at the bottom than for the undistorted hull. In fact the predicted wake is not too unrealistic for the foreshortened model as can be seen from fig. 22: the measurements shown there were made in the course of the experiments described in the next section.
86
Wind
tunnel
experiments
For the present whether
realistic
results,
tunnel,
it was
this model
intended
should
comparison
and error
experimentation
much
more
was
tested
insert
time,
tunnel
working
seetion
in the two faeilities. established
tunnel.
For future
applieations
especially
where
not be neccssary may weIl
be sufficient
significantly
the wind
it would
simply
A wind
model
be tested
flow
tunnel
tunnel,
is
the model sleeve
approximately thus
the ensur-
be assumed that any
therefore
be duplicated
would
model
to be obtained
naked
There
hull wake,
it
which
then be no necd
in the octogonal
in the normal
it may
Instead,
arrangements would
in the
technique,
quickly,
pressures.
effeetive
this wake.
tunnel
it
the necessary
an octogonal
to find deflector
improve
to test
with
cavitation
a realistic
However
Aecordingly
simulated
tunnel
have
to measure
establishing
tunnel.
of the foreshortened
results
arrangements,
at the same blockage ratio
operate
It could
cavitation
after
fitted
in the wind
pressure
to find the apprcpriate
of the cavitation
would
give
that
results.
to perform
for such a purpose.
in a wind
ing that the model
wake
cQnsuming
as in fig. 23. The sleeve
cireular
flow deflector
in the cavitation
eonvenient
could
fluctuation
the full scale
trial
devices
enable
with
very
to
in the cavitation
various
have been
model
from the outset
with
would
correcting
it was desired
be tested
18. This would
to be measured
for direct
where
model
or not the foreshortened
as in fig.
levels
foreshortened
investigation,
establish ultimately
with
wind
sleeve tunnel
insert
working
seetion. The first
part
of the present
eonsisted
in attempt
it beeame
elose
the right
hand
to modify
to the assumed side of fig.
fitting
aperforated
in fig.
18 for the final
made
experiments
plate
the flow steadier
in the wind
the bare model
wake
so that
full scale
ship wake,
21. The first
improvement
to the aft model
cavitation
and slightly
tunnel reduced
tunnel
support,
shown
involved as shown
configuration. the wake
on
This
intensity,
87
perhaps due to an alleviation of the adverse effects of tunnel blockage in the rather constricted working section. The measured wake shown in fig. 22 was with this plate fitted, but it was clearly still far from the required one of fig. 21. The closest approach to this that could be obtained, after many trials of alternative arrangements, was with a pair of vortex generators, similar to but larger than the scaled flow deflectors, at station 11/2 near the 3 m waterline, as in figure 18. These produced longitudinal vortices inducing an artificial cross-flow in the boundary layer to simulate more closely the required flow. The vortices were very concentrated for a short distance downstream of the generator tips, where they could be visualized by tufts which rapidly spun round. However vortex bursting then seemed to occur, with the vorticity becoming more widely diffused. This took piace upstream of the flow deflector position. Thus it could be assumed that if the propeller plane wake was realistic, the boundary layer flow at the flow deflector plane would also be sufficiently similar to that on the full scale ship. This would mean that the flow deflectors could be expected to behave in a similar way on the model as on the ship. The final
effective
as can be seen it was
certainly
generators. proceed
naked
hull wake
from a comparison far better
It was considered
to the investigation
of the wake
induced
achieved
was not perfect,
of fig. 24a with
than without
fig.
the upstream
to be sufficiently of the additional
21, but vortex
realistic
to
modifications
by the flow deflectors.
As mentioned above, two deflector arrangements were tried on the ship, one with the two lower pairs of deflectors sketched in figure 18, and the other, more successfully, with the additional upper pair as weil. It was conjectured however that the two upper pairs of flow deflectors, or conceivably even the top pair alone, would also have been effective. Therefore it was decided to investigate these arrangements as weil as the ones actually used on the ship.
88
The resulting wakes are shown in fig. 24. It ean be seen that the biggest improvement over the wake with no flow defleetors is produeed by the 3 pair eonfiguration, as aetually used on the ship, but the two upper pairs of defleetors give nearly as good a result. The two lower pairs give a signifieant, but more modest, improvement, and there is also some improvement with the upper pair alone. Thus
on the basis
expeeted
that
the 3 pair
defleetors
would
and noise,
that
benefieial, produee
of the wind be very
a small
or upper pair
the upper
experiments
2 pair
benefieial
the two lower
and that
tunnel
it would
arrangements
for alleviating arrangement
of flow vibration
would
pair of defleetors
be
be quite
alone
would
improvement.
Com arison with towin
tank ex eriments on undistorted model
Different eonelusions would however have been reaehed from tests on exaetly sealed defleetors on anormal towing tank model. Fig. 25 shows that although the three defleetor arrange~ ment produees a signifieant, though less marked, improvement than that shown in fig. 24, the arrangement with the two lower pairs of defleetors aetually makes the wake slightly worse. Thus it would be expeeted to be of no benefit at all on the ship.
Cavitation Pressure tunnel
tunnel
experiments
fluetuation
levels
at the refleetion
eorresponding
to ballast
123 rpm. Fig.
26 shows
withforeshortened were measured
plane
above
eonditions the harmonie
dimensional
pressure
fluetuation
the various
flow defleetor
model
in the eavitation
the serew
at eonditions
on the ship at 115 and eomponents
levels
arrangements.
K
p
=
of the nonp/p n2D2
for
89
The results broadly confirm the expectations of section: Wind tunnel experiments ..., page 5, as inferred from the measured wake flows of fig. 24, though the upper pair of deflectors alone appears in the pressure measurements to be about as good as the two lower pairs, whereas the latter arrangement would have been expected to be better than the upper pair alone, according to fig. 24.
Comparison
with
ship results
Results are available for the ship in ballast condition with no flow deflectors, with the two lower pairs, and with all three pairs, and in load condition with all three pairs of deflectors only. Qualitatively pairs ment
gave
the finding
some
is borne
gland
improvement
shows
the results
big improvement speed
is reduced
pair
configuration
hull
configuration.
figures
on the other measured fig.
29.
those
refer
and the three
pairs
a big improve-
levels
measured
fluctuation
pairs
levels
more
the stern
is a considerable
pressure measured there
on the model
levels
is good
seem
things
speeds
however
to make
a
at 123 rpm, at that
the three
over the naked
28 are considerably
tests
in fig.
26. These
In the load condition,
agreement
and on the ship,
28
level
improvement
in fig.
as fig.
worse
vibration
condition.
also measured
confusing,
in the model
to the ballast hand,
gland
at the stern were
of deflectors
(fig. 27). At both
The non dimensional than
the two lower
at 115 rpm but to make
the fact that
larger
draft
are somewhat
that the two lower
despite
in ballast
out by vibration
(fig. 27). Pressure
and here
that
between
the levels
as can be seen
from
90
Possible
causes
One obvious figs.
of differences
possible
explanation
model
does
the ship.
Certainly
than
not simulate
that
aimed
peak
at, shown
in fig.
in fig.
fig. 28, and for the apparently
deflectors quite
in fig.
similar, the main
that
the model
26. However
cause
are much
The scale
are for a level
the ballast
case,
An alternative
explanation
of air bubbles then.
and may
are not
These
ment
was considered
ship
cavitation
tunnel
the effects
of such entrained pressure
bow, which along
in
levels
under
similar
causes
to
entrainof the
to simulate
and this may well
at ballast
the
condition.
do not attempt
bubbles,
breaks
and bubbles
air bubble
in the ballast
tests
quan-
pressures.
is closely
in /8/, where
experienced
a great
immersed
to be one of the primary
The present
scale
from
between
the cavitation
is fully
The bow for this
for the ship discussed
why the model
that this
from those
may be carried
affect
the bulb
fluctuations
indicate
and the model
condition
at the bulbous
bubbles
that
pressure
also
is different
different
in the ballast
significantly
formed.
here
be expected
29 shows
for the discrepancies
is formed
In the load condition
would
are
26.
26 and 28 is that
the surface hull
fig.
of
the wake
it would
be noted,
not much
reduc-
and load wakes
in modelling
of plotting
in fig. 26
excessive
too low. Fig.
26 and 28, it should
predictions
tity
the ballast
less
account
by the 3 pairs
for the load condition
which
is not the case.
figs.
about
of the discrepancies,
tests
levels
that of figs.
brought
flow deflectors
so if such a deficiency
were
pressure
levels
that on
21. This might
compared
in the pressure
on
24a is a little
pressure
tion
without
between
accurately
for the lower with
levels
results
flow deflectors
sufficiently
the wake
and shi
of the differences
26 and 28 is that the wake without
the model sharp
between
draft
be
are lower
than on the ship.
Be that as it may, even if quantitatively
the results from the
foreshortened model are judged to be in error, they give a qualitative picture of the effects of the various deflector ---...--
91
arrangements which is substantially correct. It is felt, therefore, that such a technique is a useful one to use in any future tests of flow deflectors for curing vibration problems, and as suggested, wind tunnel tests alone, with assessment of the resulting wakes, would probably be sufficient for this purposes.
Concluding remarks The experiments described in the foregoing are examples of how useful the wind tunnel can be as an adjunct to the investigation of what at first sight my seem to be purely hydrodynamic problems.
Acknowledgements This work was supported by the Ship and Marine Technology Requirements Board of the Department of Industry, HM Government, UK. Acknowledgement is also due to the industry sponsors of the recently completed PHIVE programme.
References
/1/
Gadd, G.E.:
"A Simple Calculation Method for Assessing
the Quality of the Viscous Flow over a Ship's Stern". Paper presented at the International Symposium on Ship Viscous Resistance, SSPA, Göteborg, Sweden, 1978.
/2/
Klebanoff, P.S.:
/3/
Bradshaw, P.:
NACA Report 1110, 1952
"Conditions for the existence of an inert-
ial subrange in turbulent flow". search Council R&M 3603, 1969.
Aeronautical
Re-
/4/
Townsend, A.A.: "The structure of turbulent shear flow". 2nd edition, Cambridge University Press, 1976.
/5/
Odabasi, A.Y. and o. Saylan: "GEMAK-a method for calculating the flow around the aft-end of ships". 13th Symposium on Naval Hydrodynamics Tokyo, 1980.
92
/6/
Kline, S.J. and A. McClintock: "Describing uncertainty in single-sample experiments". Mechanical Engineering Dept Standorf University, Jan. 1953.
/7/
Gadd,
/8/
Takekuma, K.: "Effect of air bubbles entrained from bow on propeller induced pressure fluctuation". Mitsubishi Technical Bulletin No 140, June 1980.
G.E.: "Flow deflectors - a curve for vibration". The Naval Architect, No 6, 1980, P 238.
-
Fi g
.
13
93 -
SKETCH
OF
BE I NG
FITTED
FLOW TO
DEFLECTORS 51-11 P
7m
7m
Sm
I
I I
3m
O.7m
FRO
HULL
~\
07m
FROM
HULL
-i
J I J
\ \ \
\ \ \ MODEL
SCALE
Fig.
14
FULL
PREDICTED
WAKE
CONTOURS
AT
PLANE
OF
SCALE
FLOW
DEFLECTORS
3m
-
._HULL.
94
_--
SURFACE
,
3,,,
Sm 7m
-
EOGE OF
80UNOARY
LAYER
"2
-
---
--
--
-
3m
--
--- ---Fig.
15
CALCULATED AND MEASURED FLOW DIRECTIONS MODEL IN BALLAST CONDITION
7m
HUL.L. SURFACE
-
3/"
_ _-
EOGE
OF
FOR
BOUNOARY L.AYER
-
Sm
3m
-
,.,---
Fig.
16
CALCULATED CONDITION
--
---
FLOW DIRECTIONS
FOR SHIP
IN
BALLAST
95
o
120
\00 Z, mm 4'3Sm
W...TEAL.INE
80
(;)
60 .
o
40
20
0-8 u / Uo
'-0
60 Z. mm 40
'-45m
W...TERL.IN!: (;) (;)
20
o
Fig. 17
CA!..CUI."TEO aOUNOARY
PEAFOR"'TED
e 0.6
0.2
0., U/Uo
\'0
CURVES COMPARED WITH MEASUREO POINTS FOR L"VER ON '130 SCALE MODEL AT STATION 3/4
PL TE TOP OF TUNNEL. ;,---PERFOIIATED I I I
PLATE
I I
VORTEX GENERAT 3
;;
,l4 , I '2
I
2
SHIP
,
'y
l
5
,~AAAL.L.EL. SECTICN I I
Fig.
18
DOUBLE
HULL
FORESHORTENED
MODEL
IN WATER
TUNNEL
51. 2
-
-
96
HULl.
-
SURFACE
___
EOGE OF 8OUNOARY LAYER
---
7m
Sm
:!Im
--
.--
-Fig.
Fig.
19
20
CALCULATED FLOW DlRECTIONS FOR FORESHORTENED MODEL WITHOUT UPSTREAM VORTEX GENERATORS
PROPELLER PLANE WAKE CONTOURS AT MODEL SCALE: LEFT, PREDICTED: RIGHT, MEASURED
-
97
-
Fig.
21
PROPELLER PLANE WAKE CONTOURS AT FULL SCALE: LEFT, PREDICTED: RIGHT, INFERRED FROM MODEL SCALE MEASUREMENTS
Fig.
22
PROPELLER PLANE WAKE CONTOURS FOR FORESHORTENED MODEL: LEFT, PREDICTED : RIGHT, MEASURED
-
-
98
WATER
TUNNEL
SECTION
OCTACONAL SLEEVE INSERT
SUPPORTS FOR INSERT
MAIN WIND TUNNEL SECTION
Fig.
23
OCTAGONAL
INSERT
TO
WIND
TUNNEL
SIMULATING
CAVITATION
TUNNEL
180'
180.
180.
(0)
(bJ
(cJ
180'
WORKING
110'
Fig. 24 WAKE eONTOURS IN UPPER PART OF PROPELLER Dlse IN WIND TUNNEL c, LOWER 2: d. UPPER2: c. UPPER 1 '"'UMBER OF 'pAIRS OF FLOW DEFLECTORS: 0, NONE: b.3:
SECTION
- 99 -
(b)
(0 )
Fig.
25
WAKE CONTOURS IN UPPER PART OF PROPELLER DISC IN TOWING TANK NUM8ER OF PAIRS OF FLOW DEFLECTORS: 0, NONE: b,3: c, LOWER 2
-OJ
~p '01
0
~~I :/ 3 4-
:/ 3 4
0
b
-03 Itp -02
-01
0
(cj
:/ 3
10
1 :2 34
. .
115 rpm
1 :2 3 4-
Fig. 26 PRESS URE MEASUREMENTS ON MODEL NUMBER OF PAIRS OF FLOW DEFLECTORS: a, NONE
1 :2 3
c
:< 3
'-
FOR b. 3
J1L I :/ 3
10
d
10
xBR
C
1:/3rpm
JlJl
~-~
1 :< 3 4-
BALLAST CONDITION c. LOWER 2 : d. UPPER
I :/ 3 'I.
2:
I!:, UPPER
x BR
1
-
100
o
b
c
mm/s
o
Fig.
1 2 3
JL , 2 34
J"
I 2 3
J"
IC BR
27 PEAK VERTICAL VIBRATION VELOCITY AT STERN GLAND ON SRIP IN BALLAST CONDITION AT ]23 rpm. NUMBER OF PAIRS OF FLOW DEFLECTORS: a, NONE: b, 3: c, LOWER 2
O'r .0. '0
115 rpm
I
o'r
oJ
-J I 2 J .. 0
JL
..~ I
2 1 ..
1 :2 3 ..
MODEL.
SHIP
.008
JI SA
b
'0
'0.
'05 121 rpm
'0 '0.
o '03
Fig.
'02
'0,
0
Fig.
1 a 3 ..
1 :2 3 4.
,
2 J ... 11eR
28 PRESSURE MEASUREMENTS ON SRIP IN BALLAST CONDITION.NUMBER OF PAIRS OF FLOW DEFLECTORS:
a, NONE: b, 3: C, LOWER2
29 PRESSURE MEASUREMENTS FOR LOAD CONDITION WITR 3 PAIRS OF FLOW DEFLECTORS AT ]23 rpm