<p>Shiv Nadar University is a comprehensive, multidisciplinary, research-focused, and student-centric University offering a full range of academic programs at the undergraduate, postgraduate and doctoral level. With state-of-the-art infrastructure, the University comprises of academic wings, sophisticated labs, international standard sports facilities, amphitheaters, auditorium, conference rooms and smart classrooms. The University&rsquo;s goal is to become internationally recognized for the quality of its research and creative endeavors and their applicability to improving quality of life, generating new insights and expanding the boundaries of human knowledge creativity. Committed to excellence in teaching, research and service, the University aims to serve the higher education needs of India and the world beyond.</p>

Shiv Nadar University

Diverting or deflecting sediments is an essential part of river training. Under the effect of an induced helical motion, the submerged vanes are best known for deflecting sediments. This study presents current state-of-the-art information on employing submerged vanes for sediment deflection, as well as concluding notes outlining the current knowledge’s limitations and suggestions for future research on sediment deflection using submerged vanes. The analytical background for basic physics of submerged vanes’ operation is first described. The paper then moves on to a thorough examination of vane design parameters based on analytical relationships. A brief overview of the applications of submerged vanes is also included in the paper. A review of recent studies aims at designing a layout of submerged vanes to assist in river training tasks, such as river bends protection, sediment exclusion at water intakes, improving safety at bridges on waterways, improving inland navigation is provided to this end. The study also presented a future program of research on submerged vanes for improving inland navigation in braided rivers. The major lag in literature is a lack of information on macro turbulence and the associated sediment motion induced by the wake of the submerged vane. © 2022 Indian Society for Hydraulics.

World University root node

Civil Engineering

(SoE) School of Engineering

ISH Journal of Hydraulic Engineering

A review of sediment deflection in rivers using submerged vanes

India currently has 5264 large dams in operation and 437 large dams under construction. Many of these dams do not match the emerging hydro-meteorological, hydraulic aspects. Safety of these dams is important to prevent collapse triggered by climate change effects. The increase in inflows to dams due to cloud bursts may cause dam safety concerns due to enhanced hydrodynamic forces. The main focus of this review is to get an insight into the events of cloud burst and GLOF which threaten dam safety. There are 65 completed and 11 under construction dams in India in the category of "Dams of National Importance" of which 22\% of the completed projects are older than 25 years. The review on failure due to cloud burst on few dams nationally and internationally has been done. The behaviour of Tehri Dam and Nathpa Jhakri dam in the past during the Cloud burst and GLOF occurrences and the importance to have a storage capacity for the hydel dams has been discussed along with the discussion on the necessity to increase the spillway capacity of Matatila dam. The scientific tools for conducting incisive case studies are highlighted to develop adaptive measures to deal with the resulting circumstances. © 2019, Central Board of Irrigation and Power. All rights reserved.

Center for Environmental Sciences & Engineering

Water and Energy International

Review of climate change impacts on dam safety and flood mitigation issues in India

Sediment particles entrainment from the channel bed is influenced by flow turbulence which creates fluctuating shear stress at the bed. Sweep quadrant event is considered to be most important for entrainment of sediment particles as it exerts forces in the flow direction resulting in rolling and sliding of sediment particle. Similarly, the ejection event has been considered important for sediment transport since these events maintain the sediment particles in suspension. In this paper, the nature of bursting events and in particular, the sweep events were studied in a model of braided river with a central island. The instantaneous velocities of flow were measured using the ADV. The turbulent stresses were determined from these instantaneous velocities. Box–Cox transformation is applied to transform the original data into a normally distributed data. The velocity measurements near the braided bar were made at 12 vertical sections using an ADV. The maximum value of turbulent kinetic energy and the Reynolds shear stress was found to occur near the bed level. These turbulent parameters have greater values for scouring points, this shows that these parameters are related with the scouring near the braided bar. © 2016 Indian Society for Hydraulics.

Experimental study on bursting events around a bar in physical model of a braided channel

In recent years, spillway rehabilitation has increased in importance and become the subject of many projects worldwide. One solution for this problem is the implementation of a new type of labyrinth spillway, called Piano Key Weir (PK-Weir ). This is an excellent alternative for increasing the overflow capacity of existing dams. Similarly to traditional labyrinth weirs, the hydraulic capacity of a PK-Weir is a function of its geometrical characteristics. Currently, there is a lack of systematic experiments, and the existing data does not allow the proposition of a universal design procedure. This paper reviews the previous studies on the efficiency of planned and built PK-Weirs. The results are evaluated by comparing an actual PK-Weir's discharge to that theoretically obtained for a sharp-crested spillway with crest length equal to the width of the PK-Weir for a given hydraulic head. On the basis of this evaluation, a preliminary design procedure is proposed. © 2012 American Society of Civil Engineers.

Journal of Hydraulic Engineering

Discharge capacity of piano key weirs

<p>Piano Key Weirs are modified version of labyrinth weir with innovation to improve discharging capacity and more compatible for constructing on a existing or new spillway with lesser space requirement and structural stability. The objective of this study was to identify the Piano Key Weir in which the maximum discharge capacity at different UW with p (height of weir) could be achieved. To achieve this for different flow conditions, length magnification ratio (L/W) is taken from 3.56 to 7.40. Also, other parameters are taken in different combinations for getting optimum configuration of Piano Key Weir for better performance. With this in view, three phases of experimental campaign on eighteen Piano Key Weir models are reported in this paper. The ratio (r) of Piano Key Weir to linear weir discharge for a given head was seen to be more than one and found to increase with magnification ratio L/W upto a certain limit of h/p ratio. It was also found that performance of ratio of inlet and outlet cell width was best when two cells were of same width. The analysis of discharge coefficient variation is correlated with h/p. © 2011 Taylor &amp; Francis Group, LLC.</p>

Experimental study of hydraulically efficient piano key weir configuration

Free-flow spillways are simpler and safer than gated ones, but the low specific flow of their traditional shapes requires high spilling nappe depths and thus huge losses of storage (100 × 109m3 worldwide). A newly evolved shape of free-flow spillway (the "Piano Key weir") has the potential to increase the specific flow as high as fourfold at lower discharges. It could substantially increase, at low cost, the safety and the storage and/or the flood control efficiency of many existing as well as new dams. It is thus very advantageous to increase the specific flow as much as possible. Some tens of existing spillways have been designed accordingly as vertical walls on a flat bottom, with a trapezoidal labyrinth layout which is much longer than the spillway length (often four times). They usually double the specific flow of an Ogee Spillway. Piano-Key Weir derives its name from its plan-form shape which looks like a 'piano-key'. It is configured as polygonal walls such as to provide a much longer crest length than the conventional ogee spillways. This paper presents experimental data analysis on this new (not patented) solution in order that: Increasing the storage of many irrigation dams is justified by the increased needs or due to the sedimentation of reservoirs. Increasing the spillage capacity is often justified by a better knowledge of hydrology. Improving flood mitigation by existing dams may be very cost effective. Positive outcome of this study will be very much relevant for dam safety concerns worldwide in the context of adverse hydrological consequences due to ongoing global warming phenomenon.