An experimental study of flow into orifices and grating inlets on streets

2006 ◽  
Vol 33 (7) ◽  
pp. 837-845 ◽  
Author(s):  
Z Mustaffa ◽  
N Rajaratnam ◽  
David Z Zhu
Keyword(s):  
Experimental Study ◽  
Froude Number ◽  
Specific Energy ◽  
Discharge Coefficient ◽  
Laboratory Scale ◽  
Scale Model ◽  
The Third ◽  
Flow Through ◽  
Coefficient Of Discharge ◽  
The City

Findings are described from a laboratory-scale model of flow through orifices on manhole covers and through three types of grating inlets used by the City of Edmonton. The results demonstrated that the flow through these orifices can be calculated using an orifice equation with a coefficient of discharge equal to 0.616 in a ponding situation but decreasing with an increase in the Froude number of the flow. The roughness of the manhole cover was found to slow down this reduction. For the three gratings, the inflow can be calculated with an orifice type of equation when the gratings are submerged. The discharge coefficient in this equation is approximately constant for two of the gratings and decreases somewhat with an increase in the Froude number of the flow for the third grating if the specific energy of the approaching flow is used as the length scale.Key words: street inlet, street hydraulics, grating inlet, orifice flows.

EXPERIMENTAL STUDY OF FLOW THROUGH TRAPEZOIDAL WEIR CONTROLLED UNDER A SEMI-CIRCULAR GATE

2021 ◽  
Vol 5 (2) ◽  
pp. 245-154
Author(s):  
Bashir Tanimu ◽  
Bilal Abdullahi Be ◽  
Muhammad Mujihad Muhammad ◽  
Surajo Abubakar Wada
Keyword(s):  
Experimental Study ◽  
Discharge Coefficient ◽  
Percentage Error ◽  
Nonlinear Regression Analysis ◽  
Block Model ◽  
Gate Structure ◽  
Flow Through ◽  
Mathematical Equations ◽  
Coefficient Of Discharge ◽  
Good Agreement

Different parameters of a weir model have a great effect on the discharge coefficient. In this experimental study the effect of varying angle of a trapezoidal weir coupled with a below semi-circular gate is determined. The result showed that the higher the value of  the higher the coefficient of discharge. The respective average discharge coefficient  of the block model and the trapezoidal weir models are; 0.48031,0.48880, 0.49565, 0.49647, 0.49892 and 0.49934. As such the trapezoidal weir with   has the highest value of average discharge coefficient =0.49934. Hence the most efficient. Linear and nonlinear regression analysis were used to generate mathematical equations that can be used to predict the flow rate Q for the combined weir-gate structure and the discharge coefficient  of the most efficient model with  respectively. The discharge coefficient for the most efficient weir model was found to be 3.81% more than that of the block model (with rectangular weir). The predicted coefficient of discharge   for the most efficient model was also found to be in good agreement with the observed discharge coefficient with a percentage error in the range of  0.4%

scholarly journals Scaling for lobe and cleft patterns in particle-laden gravity currents

2013 ◽  
Vol 20 (1) ◽  
pp. 121-130 ◽  
Author(s):  
A. Jackson ◽  
B. Turnbull ◽  
R. Munro
Keyword(s):  
Granular Material ◽  
Froude Number ◽  
Particle Diameter ◽  
Granular Flows ◽  
Leading Edge ◽  
Air Entrainment ◽  
Gravity Currents ◽  
Laboratory Scale ◽  
Scale Model ◽  
Snow Avalanches

Abstract. Lobe and cleft patterns are frequently observed at the leading edge of gravity currents, including non-Boussinesq particle-laden currents such as powder snow avalanches. Despite the importance of the instability in driving air entrainment, little is known about its origin or the mechanisms behind its development. In this paper we seek to gain a better understanding of these mechanisms from a laboratory scale model of powder snow avalanches using lightweight granular material. The instability mechanisms in these flows appear to be a combination of those found in both homogeneous Boussinesq gravity currents and unsuspended granular flows, with the size of the granular particles playing a central role in determining the wavelength of the lobe and cleft pattern. When scaled by particle diameter a relationship between the Froude number and the wavelength of the lobe and cleft pattern is found, where the wavelength increases monotonically with the Froude number.

scholarly journals Experimental study to estimate the discharge coefficient over inclined side spillway

2020 ◽  
Vol 7 (2) ◽  
pp. 44-54
Author(s):  
Ayat Mehdi kadhim ◽  
Faisal A. Majid
Keyword(s):  
Experimental Study ◽  
Froude Number ◽  
Water Surface ◽  
Discharge Coefficient ◽  
Flow Direction ◽  
Surface Profile ◽  
Side Weir ◽  
Discharge Water ◽  
Water Surface Profile ◽  
Crest Length

Abstract: Weir is usually used in different hydraulic purposes, mainly for head discharge-water relationship in channels. In this research, the flow has been carried out over the side of spillway using three cases of crest inclination by means of increasing one side of the weir a half centimeter each time with constant crest length equal to 15 cm. This means that the angle θ equals to (1.91˚, 3.82˚ and 5.71˚) respectively towards of the flow and is opposite to the flow with decreasing a half centimeter. Also in case of the breadth is horizontal (θ=0), seven cases have been tested. It is known that the greater amount of discharge occurs when the breadth is horizontal (θ=0). In case of the inclination of the weir is inclined opposite to the flow direction, the discharge is greater than that of which the weir inclined towards the flow direction for all cases of inclination. The greater discharge was obtained when decreasing the angle, which is opposite to the flow direction. The amount of discharge over the side of weir decreases by increasing the angle of the slope opposite to the direction of the flow and become more decreasing in case the inclination of side weir towards the flow. In case of increasing the angle of inclination in flow direction, the amount of discharge over side weir will be decreased. The effect of Froude number has also studied with the discharge coefficient and found that, they are proportionally related to each other. Also the water surface profile along the side spillway weir is studied and taken under consideration theoretically and experimentally in this research.

An Experimental Study of the Flow Around a Formula One Racing Car Tire

2010 ◽  
Vol 132 (7) ◽  
Author(s):  
Emin Issakhanian ◽  
Chris J. Elkins ◽  
Kin Pong Lo ◽  
John K. Eaton
Keyword(s):  
Experimental Study ◽  
Particle Image ◽  
Longitudinal Vortex ◽  
Scale Model ◽  
Reversed Flow ◽  
Formula One ◽  
Race Car ◽  
Image Velocimetry ◽  
Flow Through ◽  
Cooling Ducts

The wake of the front tires affects the airflow over the remainder of a fenderless race car. The tires can also be responsible for up to 40% of the vehicle’s drag. Prior experiments have used compromised models with solid, symmetric hubs and nondeformable tires. The present experiment acquires particle image velocimetry measurements around a 60% scale model of a deformable pneumatic tire fitted to a spoked Formula 1 wheel with complete brake geometry and supplementary brake cooling ducts. The results show reversed flow regions in the tire wake, asymmetric longitudinal vortex structures behind the tire, and a tire wake profile that is unlike previous experimental results and postulations. The flow through the hub of the wheel causes a shift of the wake inboard (toward the car) so that the outboard side of the wake does not extend past the outline of the tire.

PENGARUH PEMANFAATAN TEKNOLOGI INFORMASI TERHADAP KEPUASAN END USER COMPUTING DENGAN KETIDAKPASTIAN TUGAS SEBAGAI VARIABEL MODERATING

2013 ◽  
Author(s):  
Herawati M
Keyword(s):  
Information Technology ◽  
Primary Data ◽  
End User ◽  
Moderating Variables ◽  
The Third ◽  
Use Of Technology ◽  
Task Uncertainty ◽  
Independent Variable ◽  
The City ◽  
End User Computing

This study aims to use information technology, uncertainty or moderation duties and interactions between task uncertainty with the use of information technology to end user computing satisfaction. In this study used 70 respondents who actively use computers and working with several companies banking on the city of Padang. The data used are the primary data obtained through questionnaires. The study used three types of variables, the first is the independent variable, namely the utilization of information technology, both moderating variables, namely the uncertainty of the task, the third is the dependent variable is satisfaction of end user computing. The stages of hypothesis testing is done by using a regression model of moderating and statistical t-test. Based on the results of testing the first hypothesis (HI) was found to significantly influence the utilization of information technology to the satisfaction of end user computing. The second hypothesis (H2) testing results found that task uncertainty did not significantly influence the end user computing satisfaction. The third hypothesis (H3) testing found that the interaction or moderation between the use of technology with task uncertainty no significant effect on end user computing satisfaction.

Humanist Engagements

2017 ◽  
Author(s):  
Howell A. Lloyd
Keyword(s):  
Educational Provision ◽  
The Third ◽  
Social Composition ◽  
Cultural Life ◽  
Law Faculty ◽  
Editorial Work ◽  
Governmental Institutions ◽  
The University ◽  
The City

Bodin arrived in Toulouse c.1550, a brief account of the economy, social composition, and governmental institutions of which opens the chapter. There follow comments on its cultural life and identification of its leading citizenry, with remarks on the treatment of alleged religious dissidents by the city itself, and especially on discordant intellectual influences at work in the University, most notably the Law Faculty and the modes of teaching there. The chapter’s second part reviews Bodin’s translation and edition of the Greek poem Cynegetica by Oppian ‘of Cilicia’, assessing the quality of his editorial work, the extent to which allegations of plagiarism levelled against him were valid, and the nature and merits of his translation. The third section recounts contemporary wrangling over educational provision in Toulouse and examines the Oratio in which Bodin argued the case for humanist-style educational provision by means of a reconstituted college there.

scholarly journals Pivoted-Pad Journal Gas Bearing Performance in Exploratory Operation of Brayton Cycle Turbocompressor

1968 ◽  
Vol 90 (4) ◽  
pp. 687-696 ◽  
Author(s):  
R. Y. Wong ◽  
W. L. Stewart ◽  
H. E. Rohlik
Keyword(s):  
Experimental Study ◽  
Journal Bearing ◽  
Inert Gas ◽  
Brayton Cycle ◽  
Ambient Conditions ◽  
Operating Characteristics ◽  
The Third ◽  
Loading Device ◽  
Bearing Design ◽  
Gas Bearing

This paper describes findings obtained to date in the area of journal gas bearings from an experimental study of a Brayton cycle turbocompressor designed for the requirements of a two-shaft 10-kw space power system. The journal bearing design utilizes three pads pivoted on conforming balls and sockets. Two of the pivots are rigidly mounted to the frame, and the third pivot is mounted to the frame through a low-spring-rate diaphragm. This paper describes the salient package and bearing design features and then presents the principal results obtained from testing the package in both a spin calibration rig and operation at design temperature conditions with an inert gas. The results discussed include (a) the successful use of a pneumatic loading device to vary pad load during operation, (b) the operating characteristics of the bearings as obtained over a range of pad loads and ambient conditions, (c) structural and dynamic behavior of the bearing-support system during design temperature operation and (d) a discussion of the wear characteristics of the conforming ball-and-socket pivot as obtained from the tests made to date.

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