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In-Depth Information
carriage motion remotely (direction and speed, traverse and rest periods, including
operation over the Internet); remote recording of real-time high-frequency data
as the carriage moves along the flume (including high-volume video records);
maximisation of installation aesthetics (including minimization of system noise
and cabling); and maximisation of safety (including safety of power supply in the
peopled and water-filled environment, having carriage control and data-logging
removed from the moving carriage, and removing the potential for snagging or
damage of power and data cables as conventionally strung to moving carriages). The
contactless system means that the carriage simply sits on top of flume rails, with
power (for instruments and the carriage drive) and data transferred to and from the
carriage in the absence of any fixed physical connections between the carriage and
non-carriage objects.
With continuing development of the IPT carriage (e.g. El Sammak
2006
; Ibrahim
2006
), real-time data that can now be transmitted, analysed, displayed, and saved
as the carriage moves include fluid velocities (via ADVs or PIV) and evolving
sediment-bed morphology (e.g. using videos or acoustic or laser-based distance-
measurement systems). As part of the development, a Java-based software applica-
tion “E-Flume” has been developed to combine all of the functionality of existing
software applications for the carriage motor and identified flume instruments (e.g.
El Sammak
2006
; Ibrahim
2006
). Remote control of the carriage and instruments,
e.g. via the Internet, has also been established utilising the IPT link.
4 Conclusions
Leonardo da Vinci's recognition of the value of experimentation is quoted by Levi
(
1995
): 'First I shall try test by experiment before I proceed further, because my
intention is to consult experience first, and then with reasoning show why such
experience is bound to operate in such a way. And this is the true rule by which those
who analyse the effects of nature must proceed; and though nature begins with the
cause and ends with the experience, we must follow the opposite course, namely,
begin with experience and by means of it investigate the cause.' Through contem-
porary advances in measurement and analysis frameworks and methodologies, the
observations, ideas, and visions of preceding researchers regarding fluvial flows,
sediment fluxes, and morphologies are now able to be tested by today's students at
increasingly finer temporal and spatial resolutions. This chapter provides a review of
recent progressive investigations of fluvial bed morphologies involving the writer,
where the review is intended to highlight the use of developments in instrumentation
and experimental methods, along with resulting progressive advances in understand-
ing. Investigations of bedform generation using viscous-fluid, water tunnel, open-
channel, and custom-built PIV facilities are presented leading to the conjecture that
seed sand waves are formed from plane-bed conditions in a two-stage process that is
not intrinsically due to turbulent flow structures, nor a fluid-sediment flow-system
instability. Three- and four-dimensional measurements of bed-surface development
