scholarly journals Effect of canal width contraction on the hydraulic parameters and scour downstream water structures

2018 ◽  
Vol 18 (3) ◽  
pp. 93-101
Author(s):  
Mohamed A. Ashour ◽  
Tawab E. Aly ◽  
Mahmoud M. Mostafa
Keyword(s):  
Experimental Study ◽  
Experimental Models ◽  
Width Ratio ◽  
Hydraulic Parameters ◽  
Flow Properties ◽  
Canal Width ◽  
Hydraulic Conditions ◽  
Scour Hole ◽  
Design Requirements ◽  
Experimental Runs

AbstractThe dimensions of many water streams, which satisfy proper hydraulic conditions, may not be compatible with the designed dimensions of an irrigation work that needs to be constructed in some locations. The design requirements of such irrigation works may involve a contraction in the channel width in the required location. This contraction, of course, affects different flow properties and the scour hole formed downstream of these structures. Therefore, the present experimental study aims to investigate the effect of the transition angle and the contraction on the flow properties and on the scour phenomenon downstream water structures. Through 460 experimental runs, carried out on 20 experimental models, the study proved that, for an efficient hydraulic performance and economic design, the best transition angle (θ) for the approaches of water structures is 30° with a relative contracted width ratio (r = b/B) not less than 0.6.

scholarly journals Reaeration and oxygen dissipation into a circular hydraulic channel: experimental and dimensionless approach

RBRH ◽  
2018 ◽  
Vol 23 (0) ◽  
Author(s):  
Felipe Keiji Feital Harano ◽  
Murilo de Souza Ferreira ◽  
Marcos Vinícius Mateus ◽  
Deusmaque Carneiro Ferreira ◽  
Julio Cesar de Souza Inácio Gonçalves
Keyword(s):  
Interfacial Phenomena ◽  
Linear Regression Method ◽  
Hydraulic Parameters ◽  
Empirical Equations ◽  
Hydraulic Conditions ◽  
Do Concentration ◽  
Hydraulic Channel ◽  
M Estimates ◽  
Semi Empirical ◽  
Key Parameter

ABSTRACT Dissolved oxygen (DO) is a key parameter in water quality. The DO concentration in a water body can be changed by interfacial phenomena such as reaeration and oxygen dissipation, which can be represented by the coefficients K2 and KD, respectively. Few studies have jointly correlated K2 and KD with physical and hydraulic parameters of the channel. The present work investigated the behavior of these coefficients over a range of hydraulic conditions, and developed semi-empirical equations capable of relating both coefficients. Reaeration and DO dissipation tests were conducted in a circular hydraulic channel with flow velocity ranging from 0.20 to 0.79 m.s-1 and depth ranging from 0.09 to 0.15 m. Estimates of K2 and KD were performed using the non-linear regression method. Semi-empirical equations were obtained based on classical dimensional analysis and multiple regression analysis. The comparison between measured and estimated coefficients yielded R2 for reaeration and dissipation of 0.940 and 0.844, respectively. KD was higher than K2 for all turbulence levels applied at the hydraulic channel. An estimate obtained by the relation between the semi-empirical equations indicates that the transfer of oxygen in the water-air direction (dissipation) is approximately twice as fast as the transfer in the air-water direction (reaeration).

scholarly journals Experimental study of growth kinetics of CO2 hydrates and multiphase flow properties of slurries in high pressure flow systems

RSC Advances ◽  
2019 ◽  
Vol 9 (56) ◽  
pp. 32873-32888 ◽  
Author(s):  
Xiao-fang Lv ◽  
Jiang-wei Zuo ◽  
Yang Liu ◽  
Shi-Dong Zhou ◽  
Da-yong Lu ◽  
...  
Keyword(s):  
Experimental Study ◽  
High Pressure ◽  
Growth Kinetics ◽  
Deep Water ◽  
Oil And Gas ◽  
Flow Properties ◽  
Field Development ◽  
Water Transportation ◽  
Oil And Gas Pipelines ◽  
Kinetics Of

The formation and accumulation of hydrates in high pressure oil and gas pipelines bring great risks to field development and deep-water transportation.

Experimental Study on Seismic Performance of the Reinforced Concrete Grid-Mesh Frame Wall

2013 ◽  
Vol 680 ◽  
pp. 234-238
Author(s):  
Jin Li Qiao ◽  
Wen Ling Tian ◽  
Ming Jie Zhou ◽  
Fang Lu Jiang ◽  
Kun Zhao
Keyword(s):  
Experimental Study ◽  
Reinforced Concrete ◽  
Energy Dissipation ◽  
Bearing Capacity ◽  
Seismic Performance ◽  
Seismic Energy ◽  
Width Ratio ◽  
Filling Material ◽  
Energy Dissipation Capacity ◽  
Grid Mesh

In order to validate the seismic performance of reinforced concrete grid-mesh frame wall , four grid frame walls in half size is made with different height-width ratios and different grid forms in the paper. Two of them are filling with cast-in-place plaster as filling material. According to the experimental results of these four walls subjected to horizontal reciprocating loads, we know that the grid-mesh frame wall's breaking form are in stages and multiple modes, and the main influencing factors are height-width ratio and grid form, what's more, with cast-in-place plaster as fill material, could not only improve the level of the wall bearing capacity and stiffness, but also improve the ductility and seismic energy dissipation capacity.

Turbulent Flow of Water in Plane Curved Channels of Finite Depth

1963 ◽  
Vol 85 (3) ◽  
pp. 377-390 ◽  
Author(s):  
O. G. Brown ◽  
A. W. Marris
Keyword(s):  
Experimental Study ◽  
Shear Flow ◽  
Turbulent Flow ◽  
Finite Depth ◽  
Width Ratio ◽  
Mean Flow ◽  
Curved Channel ◽  
Flow Acceleration ◽  
Curved Channels ◽  
Convex Wall

An experimental study of turbulent flow in a plane curved channel of depth-to-width ratio 8:1 and mean radius-to-width ratio 1.83:1 by means of measured distributions of mean peripheral velocity and pressure and flow visualization methods using dye. It appears that due to the large depth-to-width ratio, the secondary flow, though appreciable, is apparent mainly in the end plate regions. Even so it has a pronounced effect on the flow near the inner (convex) wall. It appears that the sharp curvature is effective in quenching the turbulence of the entering rectilinear shear flow at the inner wall of the curved channel by causing a mean flow acceleration in this region. The study indicates that localized backflows can occur at the inner wall at the meeting of secondary and main flows under near-laminar conditions.

Single Transsacral Screw and Nut Stabilization of Bilateral Sacroiliac Luxation in 20 Cats

2018 ◽  
Vol 31 (01) ◽  
pp. 044-052 ◽  
Author(s):  
James Grierson ◽  
Andrew Moores ◽  
Andrea Pratesi
Keyword(s):  
Medical Records ◽  
Normal Activity ◽  
Width Ratio ◽  
Slight Reduction ◽  
Short Term ◽  
Canal Width ◽  
Long Term Follow Up ◽  
Safe Technique

Objective This article aims to describe the use of a single transsacral screw and nut in a cohort of cats with bilateral sacroiliac (SI) luxation and document its radiographic and clinical outcome. Methods Medical records and radiographic studies of cats with bilateral SI luxation managed with a transsacral screw and nut stabilization were reviewed. Short-term follow-up included clinical examination and radiographs. Long-term follow-up was via owner questionnaire. Results Twenty consecutive cats with bilateral SI luxation were included. Six cats (35%) had additional musculoskeletal injuries that required stabilization. Luxations were stabilized with a single 2.7 cortical self-tapping transsacral screw and nylon nut (a metallic nut was used in one case). Postoperative radiographs confirmed SI reduction in all cats and a mean pelvic canal width ratio of 1.21 (a ratio of ≥1.1 was considered optimal). All cats available at follow-up examination were able to walk without signs of discomfort. Evaluation of follow-up radiographs showed maintenance of SI reduction and slight reduction of mean pelvic canal width ratio (1.18). Fourteen owner questionnaires were returned (median follow-up time of 40 months): nine cats were deemed to have normal activity and five cats were reported to have slight to mild reduced ability to jump or run. Clinical Significance The use of transsacral screw and nut stabilization of bilateral SI luxation in cats is a successful, repeatable and safe technique.

Experimental Study on Effect of Ogival Bridge Pier on Scour Hole Depth

2011 ◽  
Author(s):  
Alireza Masjedi ◽  
B. Zeraat ◽  
M. Hydarnejad ◽  
Jiachun Li ◽  
Song Fu
Keyword(s):  
Experimental Study ◽  
Bridge Pier ◽  
Hole Depth ◽  
Scour Hole

Experimental Study on Seismic Performance of Composite Reinforced Concrete Block Masnory

2011 ◽  
Vol 243-249 ◽  
pp. 630-635
Author(s):  
Ying Jie Zhu ◽  
Lan Li ◽  
Wen Hui Yang
Keyword(s):  
Experimental Study ◽  
Reinforced Concrete ◽  
Seismic Performance ◽  
Failure Process ◽  
Concrete Block ◽  
Width Ratio ◽  
Steel Bar ◽  
Core Column ◽  
Constructional Column ◽  
Hysteresis Characteristics

Seismic performance under low cyclic experimental study on the six of constructional column- core column composite reinforcement concrete block masnory wall is preasented in this paper, considering the height-width ratio, window hole and without window hole, the setting of the horizontal reinforcing steel bar in the walls. Failure process and failure pattern, hysteresis characteristics, bearing capacity, ductility, skeleton curves, the viscous damping coefficient, stiffness and steel strain change the properties are analyzed, respectivily. Test results shown that this kind of composite reinforced concrete block masnory system has better seismic performance.

Design and Experimental Study on the Urea-SCR Converter Exhaust System of the Marine Diesel Engine

2013 ◽  
Vol 291-294 ◽  
pp. 1889-1894
Author(s):  
Lei Jiang ◽  
Jun Huang
Keyword(s):  
Experimental Study ◽  
Diesel Engine ◽  
Pressure Loss ◽  
Catalytic Converter ◽  
Exhaust System ◽  
Marine Diesel Engine ◽  
Exhaust Gas ◽  
Marine Diesel ◽  
New Type ◽  
Design Requirements

Urea-SCR catalytic converter can effectively reduce the NOx emission of diesel engines, but meanwhile catalytic converter will cause some pressure loss in the exhaust system, which has negative influences on the engine performances. In this paper, the method of theoretical analysis calculated the pressure loss of the SCR catalytic converter, and designing a new type of exhaust gas pipe. Through the test to meet the design requirements,the results can provide a reference for optimum design of SCR catalytic converters and assembling.

EXPERIMENTAL STUDY OF IMMERSED PLATES USED AS BREAKWATERS

1988 ◽  
Vol 1 (21) ◽  
pp. 168
Author(s):  
Alain Drouin ◽  
Yvon Ouellet
Keyword(s):  
Experimental Study ◽  
Volume Of Fluid ◽  
Irregular Wave ◽  
Wave Flume ◽  
Water Wall ◽  
Harmonic Frequencies ◽  
Hydraulic Conditions ◽  
Wave Trains ◽  
Wave Conditions

Under certain wave conditions, an immersed plate which is free to move horizontally produces what has already been called the oscillating water wall phenomenon. When this happens, the plate and the volume of fluid located under the plate move back and forth and then behave as a wave reflector. This type of breakwater was studied in a wave flume with monochromatic and irregular wave trains. Tests have provided a better understanding of the influence of certain parameters that define a plate and the hydraulic conditions under which the plate is used. Results show some interesting efficiencies and also transfert of the energy to harmonic frequencies.

Transfer Mechanism and Experimental Study of Tower of Liede Bridge

2011 ◽  
Vol 105-107 ◽  
pp. 1225-1234
Author(s):  
Wei Feng Wang ◽  
Xi Long Chen ◽  
Sai Ying Shi ◽  
Heng Bin Zheng
Keyword(s):  
Experimental Study ◽  
Plane Stress ◽  
Model Tests ◽  
Transfer Mechanism ◽  
Design Calculation ◽  
Safe State ◽  
Plane Stress Problem ◽  
Static Performance ◽  
Design Requirements ◽  
Under Construction

The text, drawing Liede Bridge as project background, gives a detailed analysis about the transfer mechanism of the cable tower, with the aid of analytic theory methods, FEM calculations and model tests. While these model tests and calculations show that, on one aspect, the cable tower meets design requirements and falls into a safe state under construction load and bridge load. On another, its theoretical values are in accordance with the test values generally. To illustrate that the cable tower's transmission is in line with the plane-stress problem in Elasticity Theory verifies the overall static performance in cable tower along with the theory of design calculation.

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