Robert J. Keller

• Doctor of Philosophy
• Professor (Associate) at Monash University (Australia)

Water security is an issue across the world as communities face ageing infrastructure, population increases and climate change. The application of digital water metering (DWM) to properties has had a demonstrable impact on water savings at the property and network levels, on efficiencies within water utilities, as well as on improvements to custome...

Business cases often strain to identify enough benefits to cover costs of digital water metering (DWM), consisting of advanced metering infrastructure and data analytics. An Australian study in 2020 identified 77 benefits of DWM, potentially generating cost savings and customer satisfaction improvements. Modeling software makes projections of m...

Research into the benefits of digital water metering (DWM) identified many benefits that were previously unrevealed in the literature. Many benefits are tangible and more easily quantified. Others, like a possible change in customer satisfaction (CS), are not. The objective of this study was to quantify any potential changes to CS from switching fr...

Business cases promoting the introduction of digital water metering (DWM) have, to date, focused on a limited number of benefits, especially water savings, metering costs, occupational health and safety (OHS), and deferral of capital works. An earlier study by the authors catalogued 75 possible benefits and developed a taxonomy based on a literatur...

Digital water meters can take Australian water utilities into the world of internet of things (IoT) and big data analytics. The potential is there for them to build more efficient processes, to enable new products and services to be offered, to defer expensive capital works, and for water conservation to be achieved. However, utilities are not moun...

This paper addresses the topic ‘Is Open Channel Worth the Effort?’ both with respect to the seminal book by Professor Henderson and the discipline of open channel flow. The writer’s early contact with Professor Frank Henderson is described. The paper then addresses the topic of open channel flow by reviewing selectively the history of the developme...

It is well known that internal water pressure, including pressure transients, in water supply networks is a major contributing factor in many pipe failures. Reliable prediction of pipe failures needs accurate information about critical contributing factors such as internal water pressure. This paper reports on a numerical study of transient pressur...

The Hoppers Crossing Pumping Station comprises two wells, each of which contains four pumps. Both wells may be considered as separate hydraulic entities as they are each supplied by separate suction lines from the penstock chamber. Within a well, each pump discharges into a rising main, which rises vertically for 40 m. A pair of rising mains then d...

Long-throated flumes (LTFs) are widely used structures for monitoring flow rates in open channels. They may be built in a variety of different shapes and are generally very accurate when operated under unsubmerged flow conditions. This paper deals with the application of LTFs to monitor the flow distribution within a complex open channel system in...

Common carp (Cyprinus carpio) is a major and widespread pest species in southeast Australia. The recent emphasis on the restoration of environmental flows to natural waterways has emphasized the issue of preventing the movement of carp into currently carp-free areas while permitting the passage of major water flows. Biological control techniques ar...

Well-designed fishways have assisted in restoring migrations and rehabilitating riverine fish species in all continents. The performance of fishways varies greatly with their type, design and operating regime, and with the species involved. Vertical-slot fishways are widely used to overcome low-level barriers, especially for non-salmonids. Importan...

In aquatic systems, in-stream structures such as dams, weirs and road crossings can act as barriers to fish movement along waterways. There is a growing array of technological fish-pass solutions for the movement of fish across large structures such as weirs and dams. However, most existing weir structures lack dedicated fishways, and fish often ha...

For small weir structures, fish often have to rely on drowned conditions to move upstream. A structure is considered drowned when the tail water level rises above the height of the barrier and the barrier becomes submerged. There is surprisingly little data on upstream fish movement across barriers under drowned conditions Important parameters affe...

The feasibility of' model testing to rate Cut-throat flumes is examined for a particular prototype structure. A model of the structure was built to a scale of I : 7.3 and a rating curve obtained. This rating was tested by examining its prediction of actual storm events against measurements of the same storm events obtained with an HL-flume situated...

A numerical model has been developed to predict the three-dimensional flow character within low slope vertical slotfishways (VSF s). The model solves the three dimensional Reynolds averaged Navier-Stokes equations, closed with the renormalised k-ε turbulence formulations. The model employs the volume of fluid method to deal with the free surface. R...

Classically, dimensional analysis is used to establish the fundamental scaling laws to predict prototype behaviour from observed model results. However, the same dimensional analysis demonstrates that it is not possible to avoid scale effects if the prototype fluid- normally water- is used in the model studies. Flow through hydraulic structures is...

Pool–riffle sequences (PRSs) are periodic river-bed morphologies with wavelengths several times the channel width. Causes of PRS formation and maintenance are not clearly understood, which may limit the effectiveness of protection and rehabilitation measures. Some confusion has existed about whether the PRS morphology is the same as or distinct fro...

Anabranching rivers have been well described and location-for-time models suggest that anabranches evolve through stages from channel development to eventual abandonment. Yet, there is much we do not know about the evolution of these systems. Our understanding of why anabranches evolve, how flow is displaced onto the floodplain or what propagates t...

The physical model is a tool for producing technically, environmentally, and economically optimal solutions for engineering problems. However, frequently it is not possible to avoid scale effects if the prototype fluid — normally water — is used in the model studies. In such cases, it is necessary to use process functions to determine the magnitude...

Rock chutes (also known as rock ramps and rock riffles) are an important technique for controlling erosion, and have been widely used in Victorian streams. Occasionally, for a number of reasons, they are damaged or fail. Based on a survey of 170 rock chutes in north east Victoria and Gippsland, eight damage or failure modes have been identifi ed. T...

The stability of the pool–riffle sequence is one of the most fundamental features of alluvial streams. For several decades, the process of velocity, or shear stress, reversal has been proposed as an explanation for an increase in the amplitude of pool–riffle sequence bars during high flows, offsetting gradual scour of riffles and deposition in pools du...

The stability of the pool-riffle sequence is one of the most fundamental features of alluvial streams. For several decades, the process of velocity, or shear stress, reversal has been proposed as an explanation for an increase in the amplitude of pool-riffle sequence bars during high flows, offsetting gradual scour of riffles and deposition in pool...

This paper presents the theory for the proper hydraulic design of rock chutes and introduces a spreadsheet-based computer program, CHUTE, to design and analyse the performance of a chute under a range of flow conditions. The design procedure allows the computation of the water surface profile on a proposed rock chute for a given design condition....

As part of an investigation into the response of pool-riffle sequences in rivers to variations in the flow rate, a method measuring the local bed shear stress on a fixed sinusoidal bed form was required. This paper describes the development and use of suitable bed shear stress probes. The direct measurement of boundary shear stress in open channel...

Pool-riffle sequences (PRS's) provide habitat for aquatic life in many natural streams. They are maintained by scour of pools and deposition on riffles during high flow. Reversals in the position of maximum velocity and shear stress between low and high flow have been used as explanations for this process. The reversals have previously been found t...

Dilute polymer solutions of sufficiently high molecular weight generally exhibit the phenomenon of drag reduction in turbulent flows. This has been usually studied by conducting either pressure drop/flow rate measurements or axial velocity profile measurements.A general correlation, based on Prandtl's mixing length model of the form, is developed h...

A hydraulic model study of an existing sloping crest Crump weir is described. Two models of scales 1:10 and 1:3 were tested. At relatively large heads, the structure behaves as one half of a flat-V Crump weir with the same transverse crest slope. At lower heads, the flow cross section becomes strongly nonsymmetrical with a consequent significant de...

The trapezoidal free overfall is analyzed by the one-dimensional momentum equation, including an assumed pressure distribution at the brink. The pressure distribution is based on previous measurements in rectangular and triangular open channels. The predicted relationship between brink depth and discharge is compared with experimental data from a l...

The development of a two-dimensional mathematical model to calculate flow characteristics in channels of compound cross-section is described. The model utilizes a previously developed depth-averaged form of the k-ε turbulence model. The model is tested against velocity and bed shear stress data taken from the literature and obtained in laboratory f...

The characteristics of cut-throat flow measuring flumes are examined with special attention to scale effects and the transition submergence at which the flow regime changes from undrowned to drowned. Three flumes were tested over a scale range of 1:4. The results for undrowned flumes indicate a small scale effect at low flow rates only. The noted s...

A design chart is developed for predicting the distance from the spillway crest to the critical point where self-aeration commences. Synthetic data covering a wide range of possible spillway flow situations are fed into a previously developed and verified theoretical model. The results are presented in terms of generalized design variables using di...

A mathematical model for the flow development upstream of the region of air entrainment on a spillway is presented. The model is based on numerical solutions of the time-averaged two-dimensional form of the Navier-Stokes equations. Predictions from the model of mean velocity distributions, boundary layer growth, and water surface profiles are compa...

THIS PAPER DESCRIBES THE DEVELOPMENT OF FIELD INSTRUMENTS WHICH MEASURE ACCURATELY AIR CONCENTRATIONS AND VELOCITIES AT POINTS IN THE FLOW.THE DEVELOPMENT INCLUDED THE DESIGN OF A FIELD UNIT BY MEANS OF WHICH DEPTH PROFILES OF AIR CONCENTRATION AND VELOCITY COULD BE OBTAINED AT VARIOUS LOCATIONS IN THE CHANNEL.SUBSEQUENTLY THESE INSTRUMENTS WERE US...