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OCR for page 1
OPENING REMARKS
Rear Admiral William C. Miller, USN
Chief of Naval Research
Ladies and gentlemen, officials and faculty of the University of
Michigan, and distinguished colleagues from the international naval
hydrodynamics community, I wish you a good morning.
As Chief of Naval Research, as steward of the Navy's science and
technology development, and as a former sailor and commanding
officer in several classes of naval ships, I have a particular interest in
naval hydrodynamics. Accordingly, it is my great pleasure to
welcome you to this symposium dedicated to the advancement of the
science and technology of naval hydrodynamics.
The symposium is unique; it is the only professional gathering
dedicated specifically to scientific understanding and technology of
hydrodynamics in support of marine applications. Among you are the
most prominent hydrodynamicists of the world. I am confident you
will find the papers to be presented here uniformly excellent. Their
selection proved a difficult task, given the number of quality papers
submitted.
This is the eighteenth symposium since the series was inaugurated
in 1956. Each symposium in the series has been sponsored by the
Office of Naval Research, the National Research Council, and a host
institution. This year, we express our gratitude to our gracious host,
the University of Michigan.
The site for these symposia rotates between the United States and
other countries, and over the years, seven different nations have
hosted your meeting. This week, in keeping with the international
flavor of this symposium, authors from 10 countries will be
presenting 51 - papers-very strong evidence that the scientific
communities are coming together to solve common hydrodynamics
problems.
The world is dramatically different today than when we began the
series in 1956. We were then at the height of the cold war; now we
are joined in a fervent hope that that period of international tension
is nearing an end. Changes that would have seemed unthinkable only
a few months ago are continuing to occur almost daily. Old barriers
are falling; new challenges arising. Defense capabilities and
requirements are being scrutinized in the light of new global realities.
There is no question in my mind that the decade of the 1990s will
exhibit a different international military presence than the decade that
preceded it, and with those changes comes a corresponding
adjustment to the distribution and focus of research and development
activity.
Political realignments and military changes notwithstanding,
geography alone tells us that the United States will remain a maritime
nation with economic and defense imperatives closely tied to free and
unimpeded access to the sea lines of communication in order to
pursue peaceful commerce. Also unchanged is the need of a maritime
nation such as ours to pursue a broad program of science to better
understand and utilize the seas that surround it.
Joseph Conrad, that great chronicler of sea lore, once said,
The sea never changes, arid its works, for all the talk of man,
are wrapped i'' mystery.
The sea probably has not changed much since Conrad penned
those words, but advances in science and technology and development
of new tools have helped to lift some of the mysteries associated with
the seagoing trades.
This is particularly true in naval hydrodynamics. With the
emerging capability to understand and predict such complex processes
as unsteady ship hydrodynamics, brought about by application of
1
supercomputers in both physical and numerical experiments, the field
is ready for new and significant scientific breakthroughs to lead to
improved propulsive efficiency, reduced ship motion, and more
accurate tracking. For many problems in hydrodynamics, however,
the level of understanding sufficient to drive technology application
remains years away and, in Conrad's words, still Are wrapped in
mystery. ~
It is the nature of scientific discovery that results frequently are
a long time coming and often not clearly foreseen. Therefore, the
Office of Naval Research has adopted the strategy of preserving our
investment in fundamental research in the field of naval
hydrodynamics, selecting the best intellects and the best ideas, while
expressing our confidence that this long-term investment will pay
valuable dividends.
The University of Michigan's selection to be host this year
reflects this investment philosophy, partly in recognition of
university's work in free-surface hydrodynamics, funded by the
University Research Initiative of the U.S. Department of Defense.
Under this program, the Office of Naval Research provided financial
support to the University of Michigan to pursue aggressive
investigation into improving the state of knowledge of ship wakes.
This initiative has been in place for four years now and has provided
the means for developing and fielding a unique instrumentation
system to quantify hydrodynamic features observed in both surface
and subsurface wakes. Several papers to be presented at this
symposium describe this instrumentation and associated research
findings. In addition, a tour of facilities dedicated to this effort will
be conducted tomorrow morning; it promises to be an eye opener for
any who may have lingering doubts regarding whether there is
significant science left to be pursued in the field of naval
hydrodynamics.
As this audience certainly appreciates, understanding the physical
mechanisms present in ship wakes can have major influence on naval
operations. In fact, the very title of this symposium proclaims its
naval orientation. Certainly, knowledge of unsteady nonlinear ship
motions is an elusive goal that may be in sight with new
advances-such as prediction of "chaotic ship motion and unsteady
ship wake-propulsion interaction. These advances should have an
impact on commercial shipping as well as military operations,
responding to the shared needs of all maritime nations.
It is in the spirit of pushing back the frontiers in basic
understanding of naval hydrodynamics that this symposium retains its
preeminence. Papers are presented, discussions--oftentimes quite
lively--are entertained, and professional and personal contacts are
made or renewed, all with the intent of fostering open information
exchange among scientific professionals. We anticipate that the result
will be a focusing of efforts and minimization of unwarranted
duplication, leading to achievement of shared objectives within the
limited resources available.
The papers to be presented cover seven topics: ship motions; ship
hydrodynamics; experimental techniques; free-surface aspects;
wave/wake dynamics; propeller/hull/appendage interactions; and
viscous effects. I have been assured by the selection committee that
they are uniformly excellent and will add to our pride in once again
sponsoring this symposium. I trust that you too will enjoy them and
will take home with you that sense of professional excitement and
interaction you came here to enjoy.
Thank you for your attention. You all have my personal best
, ,
wishes for a most productive symposium.
OCR for page 2
Representative terms from entire chapter:
ship hydrodynamics
