Cristina and John, May 2010
Home in Vienna


Collected papers  with links to PDF files
List of papers
Software
Smoothing of data
Two programs for the smoothing of data in a file: Description of
programs and their use, Download the
programs.


Lectures in hydraulics, numerics, and maritime
engineering
Introductory page
This is an introduction to
hydraulics. True energy conservation is presented, and
Bernoulli's equation is left to a subsidiary (and
occasionally useful) role. It is an integrated momentum
equation which is valid along a streamline and whose
"constant" varies across streamlines. It is absurd to
expect to apply it in fullyturbulent threedimensional
situations  for example the flow from a reservoir to a
tap in a house. It is much more intellectually honest
simply to use conservation of energy, which is more easily
derived and is a more plausible model of most hydraulic
problems.
A final year elective subject,
dealing with elementary oceanography, water wave theory,
tsunami, and coastal engineering
An introduction to waves and disturbances in channels,
measurement, and structures
An introduction to numerical methods, presenting theory
and applications largely using the optimisation package in
Microsoft Excel.

Contact
EMail
JohnDFenton@gmail.com
Home address
StUlrichsPlatz 2/4
1070 Vienna
Austria
Phones:
Home +43 1 522 7467
Mobile/Handy/Cellulare:
John +43 664 7313 1035
Cristina +43 650 762 2417
Family History
John's mother spent many years researching the Family History


Recent research
AlternativeHydraulics
is where I publish my research these days, without having
to bother about incompetent and selfinterested referees
seeking to deny me that publication. I think it was
Heisenberg (but I can't find the quote) who said "any
paper I have ever written, its importance was directly
proportional to the difficulty I had getting it
published".
This is a paper I presented to the 19th Congress of the
AsiaPacific Division of the IAHR in September 2014, Ha
Noi, Viet Nam.
Several results are obtained that contradict current
understanding and practice.
It is surprising that derivations and presentations of
the long wave equations have usually stopped short of
presenting them in useable form. In this paper they are
derived using the integral mass and momentum conservation
equations. The derivation attempts to be a true hydraulic
one, where quantities are modelled as simply as possible.
It contains certain innovations.
The traditional fiction in
hydraulics is that All Rivers Are Straight. They are not.
This corrects the long wave equations, to allow for
channel curvature in the horizontal plane, as exhibited by
most rivers!
In 1995 at the IAHR Congress in
London, I presented a paper with Guinevere Nalder, a
student of mine, on this topic. It was later expanded
considerably and submitted to the Journal of Hydraulic
Research, where it was rejected. One referee
observed that we had not allowed for the separation of
flow around bends. He presumably believed that the usual
straightchannel approximation does allow for that. This
is the theory based on that paper.
The DarcyWeisbach formulation of flow resistance has
advantages over the GaucklerManningStrickler form. It is
more fundamental, and research results for it should be
able to be used in practice. In this paper, available
results for the limiting cases of smooth flow and fully
rough flow are considered, and a general formula is
obtained for calculating resistance as a function of
relative roughness and Reynolds number. The result is
similar to one found by Yen in 1991.
MuskingumCunge flood routing has mathematical diffusion.
It and its progeny are not accurate for streams with
gentle slopes and where time variation is more rapid, and
should generally be avoided.


Coastal and Ocean Engineering  Steady water waves
A computer program ("Fourier") that solves the problem of
steadilyprogressing waves over a flat bottom is described
and made available here: Fourier
Programs that implement Stokes and cnoidal theories are
also available. The instructions file for all is Instructions.pdf.,
which is also included in Fourier.zip.
The latest changes are shown as highlighted comments.
The three wave programs are
 A Fourier approximation method whose only
approximation lies in truncating the number of terms in
the approximating series: Fourier.zip 
current version, 23 July 2015.
 An implementation of cnoidal theory, which is based on
series expansions in shallowness, requiring that the
waves be long relative to the water depth : Cnoidal.zip 
current version, 20 March 2015 (to be unpacked in a
subdirectory of the Fourier one). This is an
approximation, and not as applicable to higher waves as
the Fourier method. It can be used as a check on that
method  for long waves that are not high, both should
give the same results.
 An implementation of Stokes theory, requiring that the
waves be not too long relative to the water depth: Stokes.zip 
current version 20 March 2015 (to be unpacked in a
subdirectory of the Fourier one). This is also an
approximation, and not as applicable to higher waves as
the Fourier method. It can be used as a check on that
method  for waves that are not high or long, both
should give the same results.
