scholarly journals Discharge Coefficient of a Round-Crested Weir

Water ◽  
2019 ◽  
Vol 11 (6) ◽  
pp. 1206
Author(s):  
Jing Gong ◽  
Jun Deng ◽  
Wangru Wei
Keyword(s):  
Experimental Data ◽  
Experimental Study ◽  
Flow Rate ◽  
Empirical Formula ◽  
Laboratory Experiments ◽  
Discharge Coefficient ◽  
Data Distribution ◽  
Group Parameter ◽  
Different Shapes ◽  
Two Parameters

A model experimental study was conducted for the discharge capability of different shapes of the crest of a weir. The flow rate and the head over the weir measured by laboratory experiments were used as two parameters for characterizing the head discharge relationship. Experiments indicated that the head discharge relationship for different radii located upstream and downstream of the crest of the weir had different features. A series of detailed experiments investigated the effects of different upstream rounding radii on the discharge capability when the downstream rounding radius was constant and the round ratio between the radius of the rounded upstream corner to the weir breath in the direction of flow was equal to 1.00. Experimental results showed that the rounded upstream corner could increase the discharge capability. The discharge capability increased as the upstream round ratio became larger and did not change when the round ratio varied from 0.10 to 0.30 and from 0.75 to 1.00 in this experiment. Based on the experimental data distribution, the empirical formula for the discharge coefficient was fitted with the round ratio as the group parameter.

scholarly journals Impact of Orifice-to-Pipe Diameter Ratio on Leakage Flow: An Experimental Study

Water ◽  
2019 ◽  
Vol 11 (10) ◽  
pp. 2189
Author(s):  
Tingchao Yu ◽  
Xiangqiu Zhang ◽  
Iran E. Lima Neto ◽  
Tuqiao Zhang ◽  
Yu Shao ◽  
...  
Keyword(s):  
Experimental Study ◽  
Flow Rate ◽  
Pipe Wall ◽  
Pressure Head ◽  
Diameter Ratio ◽  
Pipe Diameter ◽  
Leakage Flow ◽  
Leakage Flow Rate ◽  
Different Shapes ◽  
Real Scale

The traditional orifice discharge formula used to estimate the flow rate through a leak opening at a pipe wall often produces inaccurate results. This paper reports an original experimental study in which the influence of orifice-to-pipe diameter ratio on leakage flow rate was investigated for several internal/external flow conditions and orifice holes with different shapes. The results revealed that orifice-to-pipe diameter ratio (or pipe wall curvature) indeed influenced the leakage flow, with the discharge coefficient ( C d ) presenting a wide variation (0.60–0.85). As the orifice-to-pipe diameter ratio decreased, the values of C d systematically decreased from about 12% to 3%. Overall, the values of C d also decreased with β (ratio of pressure head differential at the orifice to wall thickness), as observed in previous studies. On the other hand, orifice shape, main pipe flow velocity, and external medium (water or air) all had a secondary effect on C d . The results obtained in the present study not only demonstrated that orifice-to-pipe diameter ratio affects the outflow, but also that real scale pipes may exhibit a relevant deviation of C d from the classical range (0.61–0.67) reported in the literature.

Experimental Study of Various Porosity of Fractal Flow Conditioner for Orifice Plate Flowmeters

2014 ◽  
Vol 699 ◽  
pp. 915-920 ◽  
Author(s):  
Bukhari Manshoor ◽  
Mohd Fahmi Othman ◽  
Izzuddin Zaman ◽  
Zamani Ngali ◽  
Amir Khalid
Keyword(s):  
Experimental Study ◽  
Pressure Drop ◽  
Mass Flow Rate ◽  
Flow Rate ◽  
Experimental Work ◽  
Discharge Coefficient ◽  
Orifice Plate ◽  
Rate Data ◽  
Plant Industry ◽  
Measure Flow Rate

The plant industry is required to measure flow rate more accurately to meet plant operation and cost accounting objectives. The opposing concern of improving flow meter accuracy is resolved by using flow conditioners. The distance of implementation of flow conditioner upstream of the orifice plate flowmeter is also need to be addressed. Hence, in present study, an analysis of the porosity of fractal flow conditioner towards orifice plate flowmeter’s accuracy and the best distance of fractal flow conditioner upstream of the orifice plate flowmeter was determined. In an experimental work, a different porosity of the fractal flow conditioners were installed with different distance upstream of the orifice plate in conjunction with the different disturbances to assess the effects of these devices on the measurement of the mass flow rate. Data gained for all the plates showed that there is increment of pressure drop and change in discharge coefficient of the orifice with lower β value of fractal flow conditioner. Good comparisons with the previous experimental work demonstrate the fractal flow conditioner can preserve the accuracy of metering up to the level required in the standards.

Experimental Study of the Fischer–Tropsch Synthesis Using Nitrogen-Containing Syngas and Variable Pressure

2020 ◽  
Vol 20 (5) ◽  
pp. 381-390
Author(s):  
A. S. Gorshkov ◽  
I. S. Ermolaev ◽  
K. O. Gryaznov ◽  
E. B. Mitberg ◽  
L. V. Sineva ◽  
...  
Keyword(s):  
Experimental Data ◽  
Experimental Study ◽  
Flow Rate ◽  
Detrimental Effect ◽  
Space Velocity ◽  
Catalytic Performance ◽  
Tropsch Synthesis ◽  
Variable Pressure ◽  
Fischer Tropsch ◽  
Fischer Tropsch Synthesis

The effect of syngas dilution with nitrogen on the activity, selectivity and capacity of the Fischer–Tropsch reactor with a fixed granulated catalyst bed was studied during the synthesis at the integrated pilot plant for conversion of natural gas to syncrude. Experimental data were obtained at different nitrogen content in syngas: up to 2, 50 and 70 %. The analysis of experimental data shows that the dilution of syngas increases the selectivity to C5+ and decreases the selectivity to methane. The decrease in the reactor capacity observed upon dilution of syngas can be compensated by increasing the syngas flow rate. A decrease in the pressure of the Fischer–Tropsch synthesis from 2 to 1.5 and 1.0 MPa was shown to exert a detrimental effect on the catalytic performance of the process carried out with a twofold dilution of syngas at its hourly space velocity of 4000 h–1.

A Reassessment of Metering Orifices for Low Reynolds Numbers

1965 ◽  
Vol 180 (1) ◽  
pp. 331-356 ◽  
Author(s):  
L. J. Kastner ◽  
J. C. McVeigh
Keyword(s):  
Experimental Study ◽  
Reynolds Number ◽  
Flow Rate ◽  
Discharge Coefficient ◽  
Low Reynolds Number ◽  
Reynolds Numbers ◽  
Number Range ◽  
Low Reynolds Numbers ◽  
Discharge Coefficients ◽  
Low Reynolds

In view of the importance of accurate measurement of flow rate at low Reynolds numbers, there have been numerous attempts to develop metering devices having constant discharge coefficients in the range of pipe Reynolds numbers between about 3000 and 200 and even below this latter value, and some of these attempts have achieved a reasonable degrees of success. Nevertheless, some confusion exists regarding the dimensions and range of utility of certain designs which have been recommended and further information is necessary in order that the situation may be clarified. The aims of the present investigation, which is believed to be wider in scope than any published in this field in recent years, were to review and correlate existing knowledge and to make an experimental study of the properties of various types of orifice in the low range of Reynolds numbers. Arising from this it was hoped that a design might be evolved which not only had a satisfactorily constant discharge coefficient throughout the range but was also simple to manufacture and reproduce, even for small orifice diameters of the order of 0.5 in or less, and it is believed that some success in attaining this aim was achieved. The first section of the paper contains a review of previous investigations classified into three main groups. In the second part of the paper, experiments with various types of orifice plate are described and it is shown that a properly proportioned single-bevelled orifice has as good a performance in the low Reynolds number range as that of any of the more complicated shapes.

Experimental Study of a New Flow Conditioner on Disturbed Flow in Orifice Plate Metering

2009 ◽  
Vol 131 (5) ◽  
Author(s):  
A. Ahmadi
Keyword(s):  
Experimental Study ◽  
Mass Flow Rate ◽  
Mass Flow ◽  
Flow Rate ◽  
Discharge Coefficient ◽  
Swirling Flow ◽  
Reynolds Numbers ◽  
Experimental Results ◽  
Orifice Plate ◽  
Flow Measurements

The sensitivity to poor conditioned and swirling flow of flow measurements using an orifice plate are subjects of concern to flowmeter users and manufacturers. Measurements of mass flow rate under different conditions and different Reynolds numbers were used to establish a change in discharge coefficient relative to the standard one. The experimental results show that an optimally shaped flow conditioner could attenuate the effects of both swirl and asymmetrical flows. The optimization of the swirler flow conditioner is a main outcome of this work. So far the experimental results show that the cone swirler flow conditioner is the best one for swirling flow.

Control of Liquid Impingement With Electrical Field

2005 ◽  
Author(s):  
Xin Feng ◽  
James E. Bryan
Keyword(s):  
Experimental Data ◽  
Experimental Study ◽  
Flow Rate ◽  
High Speed ◽  
Volume Flow Rate ◽  
Volume Flow ◽  
Geometrical Parameters ◽  
Mode Transition ◽  
Electrical Field ◽  
Spray Impingement

An initial experimental study was performed to better understand the effect of various operating and geometrical parameters on mode transition in EHD spray impingement. Detailed experimental data is provided for the different modes observed with ethanol. Previous research has focused on the effects of applied voltage and volume flow rate with limited experimental data. Using high-speed digital video imaging, details of eight different spray modes are presented.

Experimental Study of the Diversion Crossflow Caused by Subchannel Blockages. Part II: Pressures in the Channels and the Comparison of the COBRA III-C Predictions With Experimental Data

1984 ◽  
Vol 106 (4) ◽  
pp. 441-447 ◽  
Author(s):  
A. Tapucu ◽  
S. Genc¸ay ◽  
N. Troche ◽  
M. Merilo
Keyword(s):  
Experimental Data ◽  
Experimental Study ◽  
Mass Flow ◽  
Geometric Parameters ◽  
Hydrodynamic Behavior ◽  
Flow Rates ◽  
Mass Flow Rates ◽  
Different Shapes ◽  
Plate Type

In this research, the hydrodynamic behavior of two laterally interconnected channels with blockages in one of them has been studied experimentally. For blockages of different shapes and severities, the mass flow rates as well as the pressures in the channels upstream and downstream of the blockage were determined. The experiments were conducted on two square channels separated by an intermediate plate with slots of different geometric parameters. Two types of blockages have been considered: plate and smooth. The shape of the smooth blockage was a cosine. The experimental data on the mass flow rates and pressures in the channels have been compared with the predictions of the subchannel code COBRA-III-C. It is observed that COBRA-III-C may not be adequate to describe the hydrodynamic behavior of two-interconnected channels with plate type blockages much higher than 30 percent severity in one of the channels. The limit of applicability of the code in the case of smooth blockages can be safely extended up to 60 percent severity.

EXPERIMENTAL STUDY OF THE KINEMATIC PARAMETERS OF MOVEMENT OF CARS FORCED IDLE MOTION

2018 ◽  
pp. 52-57
Author(s):  
Ivelin Kostov
Keyword(s):  
Experimental Data ◽  
Experimental Study ◽  
Experimental Research ◽  
Kinematic Parameters ◽  
Research Results ◽  
Software Product

In the work brought some experimental data of kinematic parameters of movement of cars forced idle, as the software product was used to diagnose 900 ATS, which recorded kinematic parameters of vehicle. On the basis of the conducted experimental research results are shown tabulated and analysed.

Utilization of Waste of Enzymes Biomass as Biosorbent for the Removal of Dyes from Aqueous Solution in Batch and Fluidized Bed Column

2020 ◽  
Vol 71 (1) ◽  
pp. 1-12
Author(s):  
Salman H. Abbas ◽  
Younis M. Younis ◽  
Mohammed K. Hussain ◽  
Firas Hashim Kamar ◽  
Gheorghe Nechifor ◽  
...  
Keyword(s):  
Experimental Data ◽  
Aqueous Solution ◽  
Particle Size ◽  
Adsorption Capacity ◽  
Fluidized Bed ◽  
Flow Rate ◽  
Fungal Biomass ◽  
Solution Flow Rate ◽  
Maximum Adsorption Capacity ◽  
Solution Flow

The biosorption performance of both batch and liquid-solid fluidized bed operations of dead fungal biomass type (Agaricusbisporus ) for removal of methylene blue from aqueous solution was investigated. In batch system, the adsorption capacity and removal efficiency of dead fungal biomass were evaluated. In fluidized bed system, the experiments were conducted to study the effects of important parameters such as particle size (701-1400�m), initial dye concentration(10-100 mg/L), bed depth (5-15 cm) and solution flow rate (5-20 ml/min) on breakthrough curves. In batch method, the experimental data was modeled using several models (Langmuir,Freundlich, Temkin and Dubinin-Radushkviechmodels) to study equilibrium isotherms, the experimental data followed Langmuir model and the results showed that the maximum adsorption capacity obtained was (28.90, 24.15, 21.23 mg/g) at mean particle size (0.786, 0.935, 1.280 mm) respectively. In Fluidized-bed method, the results show that the total ion uptake and the overall capacity will be decreased with increasing flow rate and increased with increasing initial concentrations, bed depth and decreasing particle size.

Asteroid collisions as origin of debris disks: Asteroid shape reconstruction from BNAO Rozhen photometry

2019 ◽  
Vol 15 (S350) ◽  
pp. 451-453
Author(s):  
G. Apostolovska ◽  
E. Vchkova Bebekovska ◽  
A. Kostov ◽  
Z. Donchev
Keyword(s):  
Laboratory Experiments ◽  
Extrasolar Planets ◽  
Shape Reconstruction ◽  
Inversion Method ◽  
Debris Disks ◽  
Shape Parameters ◽  
Zodiacal Cloud ◽  
Photometric Observations ◽  
Different Shapes ◽  
Asteroid Surface

AbstractAs a result of collisions during their lifetimes, asteroids have a large variety of different shapes. It is believed that high velocity collisions or rotational spin-up of asteroids continuously replenish the Sun’s zodiacal cloud and debris disks around extrasolar planets (Jewitt (2010)). Knowledge of the spin and shape parameters of the asteroids is very important for understanding collision asteroid processes. Lately photometric observations of asteroids showed that variations in brightness are not accompanied by variations in colour index which indicate that the shape of the lightcurve is caused by varying illuminations of the asteroid surface rather than albedo variations over the surface. This conclusion became possible when photometric investigations were combined with laboratory experiments (Dunlap (1971)). In this article using the convex lightcurve inversion method we obtained the sense of rotation, pole solutions and preliminary shape of 901 Brunsia.

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