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Investigation Of Flow Field Near A Type-A Piano Key Weir, S. Hussain, M. S. Quamar, Z. Ahmad

4th International Workshop on Labyrinth and Piano Key Weirs

Piano Key Weirs (PKWs) enhance spillway capacity and induce complex flow patterns around their inlet and outlet keys. This study investigates the flow near a Type-A PKW using Computational Fluid Dynamics (CFD). Velocity fields in the vicinity of the PKW keys were analyzed for different discharges and validated with the experimental results. As flow approaches the inlet key, the streamwise, vertical, and lateral velocity components increase significantly, with the highest velocities near the inlet key. However, near the outlet key the streamwise velocity decreases while the vertical and lateral components increase. For all the discharges, the maximum velocity was observed …

Key Width Ratio Influence On Discharge Coefficients Of Trapezoidal Piano Key Weirs Via Openfoam Simulations, Lisa Lüddecke, Mario Oertel

4th International Workshop on Labyrinth and Piano Key Weirs

Piano key weirs are characterized by complex three-dimensional flow structures with multiple parameters describing their geometry. The variation of these parameters can affect several flow characteristics such as efficiency, energy dissipation and air entrainment. Identifying the optimal geometry for enhanced hydraulic performance represents a significant challenge. Physical or numerical modeling of multiple geometric variants is necessary to identify the relevant optimal parameters. The key width ratio (between an inlet and an outlet key) represents one of the parameters that influences the hydraulic behavior of the piano key weir. In particular, it affects the discharge coefficient, which in turn affects the …

Experimental And Numerical Investigation Of A-Type Rectangular Side Piano Key Weir, Sabir Hussain, Zulfequar Ahmad

4th International Workshop on Labyrinth and Piano Key Weirs

A side weir is a structure installed along the side wall of a channel, serving multiple purposes, such as raising water levels for irrigation and drainage and diverting excess flow from rivers or channels during floods. Most studies have focused so far on linear rectangular and labyrinth side weirs, with relatively limited research conducted on side Piano key weirs. In this paper, an experimental and numerical simulation was performed on an A-type rectangular side piano key weir and a rectangular sharp-crested side weir. The diversion discharge of Piano key side weirs was within the range of ± 10% with numerical …

Sensitivity Analysis Of Piano-Key Weirs Design: Optimizing Discharge Performance Through Cfd Modeling And Empirical Insights, Fatna Oukaili, Yvan Bercovitz, Thomas Fonty, Benoit Blancher, Julien Vermeulen

4th International Workshop on Labyrinth and Piano Key Weirs

Piano-key weirs (PKWs) are widely recognized for their efficiency in enhancing spillway discharge capacity while maintaining a compact footprint. This study focuses on a parametric and sensitivity analysis of PKW discharge performance, exploring the influence of key design parameters on hydraulic behavior. By integrating experimental data with advanced computational fluid dynamics (CFD) modeling using the open-source code_saturne software, we aim to refine predictive capabilities and establish guidelines for effective PKW design. The analysis emphasizes understanding the interplay between PKW geometry and flow characteristics. The analysis considers a range of geometrical configurations, including variations in key width ratios, and inlet-to-outlet dimensions, …

An Innovative Use Of Piano Key Weirs Or Labyrinth Weirs For Long Dams In Plains, Michel Ho Ta Khanh

4th International Workshop on Labyrinth and Piano Key Weirs

Piano Key Weirs (PKW) are labyrinth type weirs but with upstream and/or downstream overhangs which allow them to have a reduced footprint at their base. The new solution of a combination of gates and PKW (or labyrinth weir) for a long dams has many advantages of costs for investment, operation and safety during high floods. If a new dam is built on a broad river where a large footprint is possible, the choice between a PKW and a labyrinth weir can arise as the difference of specific discharges of the two alternatives are relatively small and the construction of the …

An Innovative Association Of Fusegate And Pk-Weir, F. Lempérière, A. Chapuis, F. Del Rey, C. Bessière

4th International Workshop on Labyrinth and Piano Key Weirs

The combination on the same dam of Piano Key weir (PK-Weir) and fusible structures offers a highly effective passive solution for managing flood discharges. This concept first introduced by Hydrocoop in 2015 as « Innovative Associated Spillways » can leverage the strength of each system. More than 30 years after its first application, the returns of experience of the Hydroplus Fusegate® system applications on more than 80 dams in 25 different countries have confirmed their reliability in terms of sequentially overturning on the downstream side for the correct design flood. With their high discharge capacity at low head, PK-Weirs optimize …

Enhancing The Hydraulic Efficiency Of Piano Key Weir (Pkw) — Some Research Achievements, James Yang, Shicheng Li, Anders Ansell, Erik Skepparkrans, Chen Lin

4th International Workshop on Labyrinth and Piano Key Weirs

As an effective flood control structure, the piano key weir (PKW) typically features a rectangular planform for its overhangs. However, this design offers room for improvement. To enhance hydraulic efficiency, two modified PKW layouts are proposed. In the first, the floor of each key is lowered with a semicircular cross-section, forming an elliptical planform and crest. In the second, the floor is lowered with an isosceles triangular prism, creating an equilateral triangular overhang. Both modified PKW models, manufactured by 3D printing, were tested in a large-scale experimental setup. Compared to the reference weir, the elliptical-overhang PKW increases the developed crest …

Theoretical And Experimental Studies Of Non-Rectilinear Weirs -From Labyrinth To Pk-Weir, Ahmed Ouamane, François Lempérière

4th International Workshop on Labyrinth and Piano Key Weirs

Free-flow rectilinear spillways, while simpler and safer than gated or shaft spillways, have a low specific discharge, requiring a significant water head and resulting in a storage loss of more than 20% for some small reservoirs. To overcome this drawback, labyrinth weirs provide an effective alternative, allowing high discharge under a reduced head while maintaining lower construction and maintenance costs. For several decades, global research has focused on optimizing their design. In this context, a research project was initiated in 1995 at the University of Biskra to enhance the understanding of the hydraulic behavior of these structures. This project was …

Physical Model Investigations On Nappe Instabilities At Labyrinth Weirs, Michael Gebhardt, Fabian Belzner

4th International Workshop on Labyrinth and Piano Key Weirs

Free overflow hydraulic structures operating at low heads tend to develop nappe instabilities when there is no ventilation. A detailed investigation has been undertaken with a relatively large-scale labyrinth weir in the hydraulic laboratory of the BAW. A quarter-round crest was selected, because nappe instabilities mainly occur at sharp-crested weirs, which favor the development of an air pocket behind the nappe. The headwater ratios for which nappe instabilities could be observed were determined. Pressure fluctuations were measured and the frequencies determined. Adding splitters to the crest is one way to vent the air pocket and to avoid vibrations. Another possibility …

Model-Prototype Upscaling Of Pkw Discharge Capacity, James Yang, Pär Nilsen, Mats Billstein, L Johnsson, Shicheng Li

4th International Workshop on Labyrinth and Piano Key Weirs

In Sweden, many dams are undergoing upgrades to comply with the revised dam safety guidelines, which mandate higher spillway discharge capacities that their existing ones. As part of an ongoing project, a piano key weir (PKW) is proposed to replace an embankment dam and simultaneously increase the facility’s discharge capacity. The PKW configuration is evaluated in a 2 m wide flume at two geometric scales (1:35 and 1:12) to assess potential scale effects. The former comprises eight units, while the latter includes three, with all components produced using 3D printing. Results indicate that the 1:35 model exhibits a slightly lower …

Interfacial Velocity Characteristics Downstream Of A Piano Key Weir Versus A Linear Weir In A Horizontal Channel, Biruk Belay, Mario Oertel

4th International Workshop on Labyrinth and Piano Key Weirs

The downstream flow characteristics of piano key weirs (PKWs) are highly complex, manifested by significant localized self-aeration due to nape collisions and plunging jets impacting the downstream free-surface. For PKWs installed in horizontal channels, the interfacial velocity characteristics have received limited attention in previous research. In this experimental study, air-water flow measurements were conducted using a double-tip conductivity probe downstream of a PKW and a reference ogee-crested linear weir to evaluate the velocity trends under comparable hydraulic boundary conditions. The findings reveal the existence of two distinct velocity profiles downstream of piano key weirs: quasi-wall-jet and uniform profiles. The occurrence …

Effect Of Driftwood On The Hydraulic Performance Of A-Type Piano Key Weirs Situated In-Stream Or At Reservoirs, Pascal Venetz, Michael Pfister

4th International Workshop on Labyrinth and Piano Key Weirs

Driftwood is a natural part of most river ecosystems. The knowledge of its interaction with hydraulic structures, such as PKWs, is essential for two reasons: To (1) avoid uncontrolled inundations because of the level rise initiated by trapped driftwood (reducing the weir discharge coefficient), and (2) initiate the passage of the wood over the PKW, so that it remains in the river to further fulfill its environmental services. Knowledge of the conditions motivating driftwood to block at a PKW is essential. The present study accordingly focuses on the blocking probability of driftwood at PKWs and the resulting head increase – …

Floating Trees At Co-Existing Pkw & Gated Spillway, James Yang, A. Helgesson, L. Johnsson, Sc Li

4th International Workshop on Labyrinth and Piano Key Weirs

During extreme flood events, floating trees (driftwood) can pose serious risks to the safety and operation of dams. In upgrading an existing dam, a piano key weir (PKW) is introduced to replace the aging embankment dam and to increase the discharge capacity of its gated spillway. This upgrade necessitates a detailed understanding of driftwood behavior at both discharge structures, which differ significantly in design and operating conditions. To investigate this, hydraulic model tests were conducted using small, freshly cut trees—some with branches and roots—to simulate natural trees moving towards the dam. The results indicate that tree accumulation at the gated …

Faculty Senate Minutes October 6, 2025, Utah State University

Faculty Senate & Faculty Senate Executive Committee

• Call to Order
• Approval of Minutes - September 8, 2025
• University Business
• Faculty Senate Business
• Information
• EPC Report - September 4, 2025
• Report
• EPC Annual Report
• Old Business
• New Business
• Adjourn - 4:30 pm

Covid-19 Resilience In Indigenous Communities: A Community Capitals Approach, Kristin A. Drexler, Michelle Watts, Casey Skvorc, Bridget Kimsey

Journal of Indigenous Research

The COVID-19 pandemic has had a profound impact on rural American Indian/Alaska Native communities. During our multi-year study, in-depth interview data was collected in Indigenous communities from over 160 Tribal leaders and members in Alaska, New Mexico, Belize and Guatemala. In interviews, participants shared their lived experience during the pandemic, both negative impacts and factors of resilience. This article focuses on the methodology and theoretical framework of Community Capitals Framework (CCF). Using CCF, interview data was coded and analyzed using a modified CCF model. Our study aims to better understand how Indigenous communities and leaders drew on human and socio-cultural …

Educational Policies Committee Agenda October 2, 2025, Utah State University

Educational Policies Committee

• Approval of Minutes - September 4, 2025
• Subcommittee Reports
• Curriculum Subcommittee
• Academic Standards Subcommittee
• General Education Subcommittee
• Other Business
• Adjourn: 4:00 pm

Curriculum Subcommittee Minutes October 2, 2025, Utah State University

Educational Policies Committee

• Approval of Minutes - September 4, 2025
• Program Proposals
• Semester Course Approval Reviews
• Other Business
• Adjourn: 3:00 pm

General Education Subcommittee Minutes October 2, 2025, Utah State University

Educational Policies Committee

• Call to Order
• Approval of Minutes - September 4, 2025
• Course Approvals/Removals/Syllabi Approvals
• New Business
• Depth Discussion
• Additional Items
• Adjourn: 9:25 am

General Education Subcommittee Minutes September 4, 2025, Utah State University

Educational Policies Committee

• Call to Order
• Approval of Minutes - April 3, 2025
• Course Approvals/Removals/Syllabi Approvals
• New Business
• Update on Center for Civic Excellence
• Additional Items
• Review of USU's University Studies Requirements
• Adjourn: 9:30 am

Curriculum Subcommittee Agenda October 2, 2025, Utah State University

Educational Policies Committee

• Approval of Minutes - September 4, 2025
• Program Proposals
• Semester Course Approval Reviews
• Other Business
• Program Reminders
• Adjourn: 3:00 pm

Educational Policies Committee Minutes October 2, 2025, Utah State University

Educational Policies Committee

• Approval of Minutes - September 4, 2025
• Subcommittee Reports:
• Curriculum Subcommittee
• Academic Standards Subcommittee
• General Education Subcommittee
• Other Business
• Adjourn: 3:38 pm

Analytical Solutions For Transitional Flow Around Hydrometeors: Implications For Particle Dynamics And Atmospheric Modeling, Ahmad Talaei, Timothy J. Garrett

Physics Student Research

Accurate modeling of hydrometeor dynamics is critical for advancing weather and climate predictions. However, this remains a long-standing challenge in atmospheric science, particularly within the transitional Reynolds number regime, due to the lack of analytical solutions to the Navier–Stokes equations. This study presents two analytical solutions for two-dimensional, incompressible, and viscous flow around a sphere, addressing the gap between low and high Reynolds number regimes. The first framework, an extension of classical expansion methods using hypergeometric, provides a direct analytical relation that characterizes separation angle across the transitional regime. To address post- separation dynamics, a second formulation based on a …

A Survey Of Expert Decision‐Making In Functional Analysis Methodology, Audrey N. Hoffmann, Megan A. Boyle

Special Education and Rehabilitation Counseling Faculty Publications

Applied behavior analysis (ABA) relies on functional behavior assessments (FBAs) like functional analysis (FA) to address challenging behaviors effectively. FA, the most rigorous FBA method, accurately identifies underlying functional variables, guiding targeted interventions. Despite FA's proven efficacy, its integration into ABA practice is limited. This inconsistency may stem from inadequate training on FA methodologies' strengths and limitations. This study surveyed recognized FA experts to identify their recommendations for selecting FA methods. Fifteen experts participated, sharing insights on backgrounds, training needs, and decision‐making criteria across 11 FA variations. Experts emphasized considering multiple FA methodologies and offered detailed considerations for practitioners selecting …

Using Drone And Ai To Map Leaf Water Potential And Stem Water Potential For Water Stress Management In Commercial Vineyards, Alfonso F. Torres-Rua

Funded Research Records

No abstract provided.

Where The Buffalo Roam: Ungulate Influences On Quaking Aspen And Willow Communities In The Greater Yellowstone Ecosystem, J. Boone Kauffman, Dian L. Cummings, Robert L. Beschta, William J. Ripple

Aspen Bibliography

Quaking aspen (Populus tremuloides) and willows (Salix spp.) are keystone species of montane and shrub-steppe landscapes of the Western United States. Intact communities dominated by these species provide a wide range of ecosystem services, harboring an exceptional proportion of landscape biodiversity. Land use, especially overgrazing by large ungulates, is among the greatest threats to these ecosystems. To examine the effects of wild ungulates and levels of grazing at Yellowstone National Park (YNP) and the adjacent Gallatin National Forest, we sampled plant community composition and vegetation structure of aspen and willow communities both inside and outside of exclosures. …

Eng- Semicon: Understanding Nanoscale Heat Transport In Wide- And Ultrawide Bandgap Semiconductors Using Novel Deep Ultraviolet Tools, Joshua Lee Knobloch

Funded Research Records

No abstract provided.

Faculty Senate Executive Committee Minutes September 22, 2025, Utah State University

Faculty Senate & Faculty Senate Executive Committee

• Call to Order
• Approval of Minutes - August 25, 2025
• University Business
• Faculty Senate Business
• Information
• EPC Report - September 4, 2025
• Report
• EPC Annual Report
• Old Business
• New Business
• Adjourn: 4:30 pm

Faculty Senate Executive Committee Agenda September 22, 2025, Utah State University

Faculty Senate & Faculty Senate Executive Committee

• 3:00 Call to Order
• Approval of Minutes August 25, 2025
• 3:05 University Business
• 3:20 Faculty Senate Business
• 3:35 Information
• EPC Report - September 4, 2025
• 3:40 Report
• EPC Annual Report
• 4:05 Old Business
• 4:10 New Business
• Adjourn: 4:30 pm

Analysis Of Modifications To An Outdoor Field-Scale Rotating Algal Biofilm Reactor With A Focus On Biomass Productivity And Power Usage, Davis R. Haag, Phillip E. Heck, Ronald C. Sims

Biological Engineering Student Research

Filtrate from dewatering anaerobically digested biosolids is a side-stream of wastewater treatment that contains high concentrations of nitrogen and phosphorus compounds that can serve as nutrients for cultivating microalgae biomass as biofilms for bioproduct production at Water Resource Recovery Facilities (WRRFs). One system used to cultivate attached microalgae biofilms is the rotating algal biofilm reactor (RABR). A pilot RABR with 72 m² growth surface area, 11.5 m² footprint area, and a liquid volume of 11,500 L was operated in an outdoor environment at the largest WRRF in Utah, U.S.A, the Central Valley Water Reclamation Facility (CVWRF). The configuration …

Bioresources And Bioproducts: A New Open Access Journal, Ronald C. Sims

Biological Engineering Faculty Publications

Greetings to the bioresource and bioproducts community! I will serve as the Editor-in-Chief to collaborate with you as we promote the aims and scope of this new MDPI journal [1], with the help of its distinguished Editorial Board, by publishing Special Issues, Topics, Topical Collections, and Editorials, and by providing high-impact scholarship through the outstanding published work of each of our contributors.