Estimation of Energy Dissipation of Flow Over Stepped Spillways | Chapter 8 | Engineering Research: Perspectives on Recent Advances Vol. 2

Stepped spillways have been used since ancient times, about 3500 years ago. In a stepped spillway, the spillway face is provided with a series of steps from near the crest to the toe. This type of spillway is attractive for water resource management because it dissipates energy that is within the flow. When energy is dissipated by the steps, it reduces the energy reduction that otherwise must occur at the toe of the spillway. Air entrainment inflates the water flow over stepped spillways; the bulking of water due to high air entrainment forces designers to use a greater height for sidewalls in stepped spillways and for the downstream stilling basins. The purpose of this research is to investigate the energy dissipation rate in spillways with different slopes. In the present study, nine physical stepped spillway models with slopes of 15, 25, and 45 degrees and with a number of steps varying from 5 to 50 have been constructed. The crest of the spillways has standard Ogee profiles and a constant slope extends from the crest to the spillway toe. Two different-sized flumes were used in the experiments (25 and 50 cm wide). Several physical models have been constructed in order to measure the energy dissipation. The result revealed that the two most important dimensionless factors influencing energy dissipation are the Froude number and q²/(gH_dam³). Here q is the discharge per unit width of the spillway (m³/s/m), H_dam is equal to the height of the spillway and g is the acceleration of the Earth's gravity equal to 9.81 m/s2. The results showed that slope alone is not an effective factor for energy dissipation and should be used in combination with other factors. The spillway slope and step number have less impact on the rate of energy dissipation. But for a constant discharge over a stepped spillway, increasing the spillway slope, and increasing the number of steps will increase the energy dissipation. Using multiple regressions, some useful relations for determination energy dissipating are obtained.

 

Author (s) Details

 

Farzin Salmasi
Department of Water Engineering, Faculty of Agriculture, University of Tabriz, Tabriz, Iran.

 

John Abraham
University of St. Thomas, Minnesota, School of Engineering 2115 Summit Avenue St. Paul, Minnesota 55105, USA.

 

Please see the book here:- https://doi.org/10.9734/bpi/erpra/v2/3975

Safety Factor of the Open-pit Bench from Rosia Poieni Quarry, Romania | Chapter 7 | Techniques and Innovation in Engineering Research Vol. 3

 In addition to field and laboratory studies of mechanical properties, development bench stability calculations should be performed. Based on this, it is possible to determine the failure curve with the greatest risk of slippage. On the other hand, the corresponding value of the safety factor. A level of +805 m was set as his daily operating limit for the Roşia Poieni open pit mine. The bench was created by cutting a 15 m thick horizontal slice equal to the height of the bench based on this plane. Thus, there were 23 benches in the Luginish region and 27 benches in the Kuratura region. The general approach angle was set at 35°. This is the angle at which the amount of tailings and the implied aperture factor are calculated. Stability analyzes were performed for the typical slope of the quarry (consisting of 24 benches) using a single bench, a two-bench system, and two methods (Fellenius and Jambu). The values ​​obtained are above 1.3 for the single-slope and two-bank systems and above 3.754 for the typical slope, corresponding to the values ​​imposed by the standards. A polygonal slip surface was also modeled. These landslide-prone areas occur on the slopes of the Russian Punic Quarry, due to the natural cracking system of the massif and secondary cracks caused by the operations used for drilling and blasting (development technology) There is a possibility. Stability assessment was performed using the Hoek graph analysis method and the safety factor values ​​found meet the requirement of 1.3 or higher. Under these circumstances, no additional measures are required to increase the stability reserve.

Author(s) Details:

Mihaela Toderaș,
Department of Mining Engineering, Surveying and Underground Constructions, University of Petrosani, 20, University Street, Petrosani, Romania.

Please see the link here: https://stm.bookpi.org/TAIER-V3/article/view/8429

Modeling the Movement of Vehicles on the Binary Asteroid Systems | Chapter 14 | New Trends in Physical Science Research Vol. 6

 The Sphere-Restricted Full 2-Body Problem (SRF2BP), which is a celestial body system made up of a spherical celestial body and an arbitrarily shaped celestial body, is the subject of this paper's investigation into the surface dynamics of particles on the primary. While the secondary is seen as a sphere, the primary is thought of as an irregularly shaped entity. The SRF2BP's motion equation has been published. Investigated are the locations of the particle surface equilibrium, the linearized equations of the particle in relation to the surface equilibrium, and the characteristic equation of the surface equilibrium. The study of the surface mechanical environment of the unique binary asteroid pair 243 Ida and Dactyl took into account both the point mass model of Dactyl and the polyhedron model of Ida, which has 2522 vertices and 5040 faces. We outline the mechanisms via which Ida's natural trajectories and surface characteristics have an impact. Because certain trajectories are unstable, a minor disruption can result in a wide range of paths. This can aid in the development of improved space mission landers and vehicles' trajectories. Dactyl has a very minimal impact on Ida's particle velocity. However, the impact of Dactyl cannot be disregarded for some particles. To determine the characteristics of particle paths on various beginning places with static initial states, Monte Carlo simulations are performed. To observe the characteristics of particle trajectories with various beginning places and initial velocities, Monte Carlo simulations are also run. On the surface of Ida, we mapped the slope angle and the gravitational acceleration while taking the Coriolis effect into account. Plain, basin, crater, and valley areas make ideal landing targets for landers, whereas saddles, gaps, hilltops, convex surfaces, and humps make unsuitable landing targets. Concave surfaces, impact craters, and valleys with low slope angles can all be employed for vehicle landing targets and starting positions. Gaps, impact craters, and valleys with steep slopes are not appropriate for vehicle travel since it may be difficult to exit once a vehicle enters. The engineering design of the space mission to binary systems can use this document as a guide and source of suggestions.

Author(s) Details:

Yu Jiang,
State Key Laboratory of Astronautic Dynamics, Xi'an Satellite Control Center, 462 Xianning Road, Xi'an, Shaanxi, China and School of Aerospace Engineering, Tsinghua University, Zhongguancun North Street, Haidian District, Beijing, China.

Hengnian Li,
State Key Laboratory of Astronautic Dynamics, Xi'an Satellite Control Center, 462 Xianning Road, Xi'an, Shaanxi, China.

Please see the link here: https://stm.bookpi.org/NTPSR-V6/article/view/7223

An Approach of QRS Detection Using Fractional Order Digital Differentiators | Chapter 15 | Highlights on Medicine and Medical Science Vol. 16

The detection of the QRS complex is a key step in heart rate variability analysis. It has been demonstrated that methods based on differentiation are efficient and thus suitable for real-time analysis. Simultaneously, fractional order digital differentiators are gaining popularity in a variety of fields of study. The proposed transfer functions of digital differentiators are used in this research to attempt to detect QRS complexes. The Continued Fraction Expansion Method is used to obtain the transfer functions in the s domain. For discretization, the Bilinear Transform and the AlAlaoui Transform are used. QRS complexes are detected with the help of these filters. The outcome has been shown to be comparable to traditional methods.

Author (S) Details

B. T. Krishna
Department of Electronics and Communication Engineering, University College of Engineering Kakinada, Jawaharlal Nehru Technological University Kakinada, Kakinada, Andhra Pradesh, 533003, India.

View Book :- https://stm.bookpi.org/HMMS-V16/article/view/2400