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Without going into the specifics, here are the links to two publications: Turbulent Flow Structure in Large Alluvial Rivers; and Seabed Roughness. If you find them interesting but have difficulty in accessing them – write to me, I can forward you the author reprints. Hopefully they will help you answering or clarifying some of your queries – as well, lead you to other relevant references.
Further, as you know:
Any shallow-water 2D numerical modeling (see Water Modeling) suite would simulate secondary flows, eddies or vortices (see Turbulence) – provided model resolution in both space (river bed and bank) and time is fine enough to resolve the secondaries. In addition to simulating primary or mean flows (see Common Sense Hydraulics) – the secondary flow dynamics will surface if 8 sources of modeling uncertainties (as outlined in Water Modeling) – are given proper attention to while developing the numerical model.
Such 2D modeling suite also allows one to include floodplain into the modeling domain (to simulate release and storage of flows during falling and rising river stages, respectively) – if the suite is equipped with flooding and drying capabilities (such capabilities prevent crashing of model simulations while water level rises and falls).
Dr Dilip K Barua, PhD
USACE Vicksburg District partners with Engineer Research ...https://www.mvk.usace.army.mil › News-Stories › ArticleSep 9, 2022 - $1.75 trillion in flood damages have been prevented along the Mississippi River. The Yazoo Backwater project has four major features: The Yazoo ...
Rising Tide- The Great Mississippi Flood by John Barry is really intriguing to understand the history of world's one of the largest rivers and attempts to tame the river. As a primarily hydraulics engineer, I'm amazed by John Barry has explained river flow complexities without going into modeling.
I agree. Rising Tide is a marvelous book and rightly proclaimed one of the 50 best books of the past 50 years.
One issue that Barry doesn't get quite right is the argument for and against levees. He oversimplifies the arguments. Charlie Little and David Biedenharn , river engineering experts, have said that are "many simple, easy to understand AND WRONG methods to control rivers." At one point Barry acknowledges that it's a complicated set of issues but he doesn't adequately convey those complexities to the reader.
Agree on the simplification part. Although I felt Barry chose not to provide any deterministic opinion but present arguments that were presented by the experts and regulators then. There is another book - Chaos Making a New Science by James Gleick, another interesting read, on non-linear turbulent flows and many other nonlinear complexities.
Been in the Harbor of New York with a small boat and and and . Yesterday crossed the Harbor of New York on the Staten island Ferry . In the pass we had wet lands that a damper on high tides / storm surges etc. . I believe at US Government levels restoring such good . Your views sought .
------------------------------William McAnally Ph.D., P.E., D.CE, D.NE, F.ASCEENGINEERColumbus MSOriginal Message:Sent: 07-07-2023 07:43 AMFrom: Ushakar JhaSubject: Modeling unsteady flows in large scale rivers with secondary flows
------------------------------Ushakar Jha P.E., M.ASCEV.P. of Project EngineeringRye DevelopmentWinchester MAOriginal Message:Sent: 01-14-2023 03:18 PMFrom: Ebissa GadissaSubject: Modeling unsteady flows in large scale rivers with secondary flowsOne of the most interesting studies in Hydraulic Engineering is modeling unsteady flows in complex flow conditions. In unsteady flow conditions, the main channel may not be enough to carry the released discharge or flood. Thus, floodplains can be constructed with different structures and roughnesses as per required to minimize the effect of floods. In this condition, the secondary flow term is one of the key parameters to be estimated or simulated. what is secondary flow? what is the most method to estimate secondary flows? can we observe the secondary flows in the large rivers practically? any current findings about secondary flows except SKM? Any comments or suggestions are welcome!'' With Regards''Ebissa, S.M. ASCEPhD Scholar in Hydraulic Engineering------------------------------Ebissa Gadissa S.M.ASCEPhD ScholarAddis Ababa------------------------------
. . . Rather, it moves south in layers and whorls, like an uncoiling rope made up of a multitude of discrete fibers, each one following an independent and unpredictable path, each one separately and together capable of snapping like a whip . . . The collision of river and earth at these bends creates tremendous turbulence: currents can drive straight down to the bottom of the river, sucking at whatever lies on the surface, scouring out holes often several hundred feet deep. Thus the Mississippi is a series of deep pools and shallow "crossings," and the movement of water from depth to shallows adds still further force and complexity. These lines – in the simplicity of poetic and philosophized beauty – can easily fit into the descriptive specter of any large alluvial river dynamics.
As a historian and a story teller, John Barry is well poised to write it as such – and he did it brilliantly. It is not supposed to be a quantitative technical treatise – but a qualitative one – nevertheless important, as it appeals to the thinking of general public – presenting alternative views and insights for engineers to debate, ponder and even to address.
Such a writing is not easy for scientists and engineers. I remember reading the difficulty Stephen Hawking faced in writing his popular book, A Brief History of Time. His first draft was all smeared with red editorial remarks. He was told that every technical jargon and equation he wrote would scare away readers. He was advised to write in plain lucid English to capture wide swath of readers. He needed that to raise money for his expensive treatment of debilitating illness.
Coming back to Barry's 1997 book, there are many reviews on this book – here is one review (ASCE Journal of Hydraulic Engineering, August 1998) that caught my attention . . . Rising Tide is a powerful and complex story that illuminates timeless conflicts that still provoke passionate debate. The conflicts include big government versus local government, special interests versus the interests of the public, and people versus nature. The book is also a classical American story. It shows how individuals shaped major events in American history. Its main characters are heroes with good intentions, but gaping flaws. All of this makes for interesting reading by a wide audience. It is no wonder, therefore, that Rising Tide has been the subject of a number of reviews in both engineering and literary circles . . .
Summing up, Rising Tide is not and cannot claim to replace various modeling tools and efforts that are usually employed in river management works. And it is obvious, why so. Perhaps the 1995 NAP 4969 document is a good source – that presents some of the challenging issues a river engineer often encounters.
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Thanks for your insightful summary and link to the 1995 study of California's American River.