Design of the Pressurized Tepula Channel

2015 ◽  
Vol 797 ◽  
pp. 219-224
Author(s):  
Ahmed Amine Lamri
Keyword(s):  
Friction Coefficient ◽  
Water Supply ◽  
Turbulent Flow ◽  
Linear Dimension ◽  
Linear Dimensions ◽  
Sanitary Sewers

In order to calculate the linear dimension of a Tepula channel which is frequently used as water supply lines, irrigation, sanitary sewers we adopt a referential model arbitrarily chosen that gives value to the friction coefficient of 1/16. We base on the fundamental formulas of uniform turbulent flow Darcy-Weisbach, Colebrook-white. We find explicit and direct formulas for the calculation of linear dimensions of the channel.

A Study of Flow of Plastics Through Pipes

1946 ◽  
Vol 13 (2) ◽  
pp. A101-A105
Author(s):  
R. C. Binder ◽  
J. E. Busher
Keyword(s):  
Experimental Data ◽  
Reynolds Number ◽  
Friction Coefficient ◽  
Laminar Flow ◽  
Turbulent Flow ◽  
Dynamic Viscosity ◽  
Apparent Viscosity ◽  
Turbulent Viscosity ◽  
Yield Value

Abstract The pipe friction coefficient for true fluids is usually expressed as a function of Reynolds number. This method of organizing data has been extended to tests on the flow of different suspensions which behaved as ideal plastics in the laminar-flow range and as true fluids in the turbulent-flow range. In the laminar-flow range, Reynolds number below about 2100, the denominator in Reynolds number is taken as the apparent viscosity. The apparent viscosity can be determined from the yield value and the coefficient of rigidity. In the turbulent-flow range, the denominator in Reynolds number is an equivalent or turbulent viscosity equal to the dynamic viscosity of a true fluid having the same friction coefficient, velocity, diameter, and density as that of the plastic. The various experimental data on plastics correlate well with this extension of the method for true fluids.

Correlation of Barreling Effect with Boundary Friction Coefficient during Upsetting of Various Materials Workpieces under Processing Conditions

2020 ◽  
Vol 992 ◽  
pp. 751-756
Author(s):  
Volodymyr V. Kukhar ◽  
Eduard S. Klimov ◽  
S.M. Chernenko ◽  
E.Yu. Balalayeva
Keyword(s):  
Friction Coefficient ◽  
Boundary Surface ◽  
Functional Relation ◽  
Strain Range ◽  
Height Ratio ◽  
Qualitative And Quantitative ◽  
Linear Dimensions ◽  
Closed Die Forging ◽  
Structural Carbon ◽  
Structural Carbon Steel

The necessity of taking into account the barreling effect at the design of die cavities, and open die and closed die forging processes on the basis of pre-forming of billets by upsetting is shown. The division of ideas about the indices of “bulk” and “linear” barreling (barrel shape), which is determined by the ratio of the bulk and linear dimensions of the workpiece after upsetting by flat dies, was made. The functional relation (correlation) between these indices and the friction coefficient on the boundary surface between flat dies and the upsetted workpiece has been determined. The qualitative and quantitative effect of workpiece dimensions (diameter-to-height ratio), strain range, temperature (conditions of cold and hot processing) and type of forming material (structural carbon steel, some of Cu-grades and Al-grades) on the barreling effect and friction coefficient during upsetting was found. The developed method makes it possible to predict a change in the friction coefficient during the upsetting of various material workpiece under given conditions of forming and to monitor their effect to the final shape.

Computation of Normal Depth in Trapezoidal Open Channel Using the Rough Model Method

2014 ◽  
Vol 955-959 ◽  
pp. 3231-3237
Author(s):  
Bachir Achour
Keyword(s):  
Aspect Ratio ◽  
Turbulent Flow ◽  
Friction Factor ◽  
Linear Dimension ◽  
Open Channel ◽  
Discharge Energy ◽  
Flow Discharge ◽  
Model Method ◽  
Rough Model ◽  
Depth Relationship

The recurring problem of calculating the normal depth in a trapezoidal open channel is easily solved by the rough model method. The Darcy-Weisbach relationship is applied to a referential rough model whose friction factor is arbitrarily chosen. This leads to establish the non-dimensional normal depth relationship in the rough model. Through a non-dimensional correction factor of linear dimension, the aspect ratio and therefore normal depth in the studied channel is deduced. Keywords: Rough model method, Trapezoidal channel, Normal depth, Turbulent flow, Discharge, Energy slope.

Casting Quality of Gypsum Bonded Block Investment Casting Moulds

2012 ◽  
Vol 445 ◽  
pp. 349-354 ◽  
Author(s):  
Kerem Altug Guler ◽  
Mustafa Cigdem
Keyword(s):  
Surface Roughness ◽  
Investment Casting ◽  
Linear Dimension ◽  
Casting Process ◽  
Dimensional Change ◽  
Tin Bronze ◽  
Linear Dimensions ◽  
Casting Quality ◽  
Dimension Measurement

In this study surface finish and dimensional charactersitics of castings produced with gypsum bonded block investment moulds were investigated. Commercial and laboratory made gypsum bonded investment moulds were used for investment casting mould making. To compare the casting quality of the investment powders, wax patterns for surface roughness specimens and linear dimension measurement specimens were designed and produced with special geometry. Wax trees were assembled with these patterns, cylindrical stainless steel perforated flasks were settled around the trees and gypsum bonded investment slurries were filled into flasks. Conventional tin bronze was subsequently cast into these moulds by vacuum assisted casting process. Afterwards, surface roughnesses of specimens were measured and linear dimensions of wax patterns and cast specimens were compared to determine percantage of dimensional change.

Design of a Pressurized Trapezoidal Shaped Conduit Using the Rough Model Method (Part 1)

2014 ◽  
Vol 945-949 ◽  
pp. 892-898
Author(s):  
Bachir Achour ◽  
Mohammed Riabi
Keyword(s):  
Hydraulic Engineer ◽  
Turbulent Flow ◽  
Correction Factor ◽  
Complex Problem ◽  
Explicit Calculation ◽  
Hydraulic Characteristics ◽  
Entire Domain ◽  
Model Method ◽  
Linear Dimensions ◽  
Rough Model

Through the Rough Model Method (RMM) an explicit calculation is proposed to solve the complex problem of the design of a pressurized trapezoidal shaped conduit characterized by three linear dimensions. Firstly, the method is applied to a rough model of the same shape in order to establish the equations governing its geometric and hydraulic characteristics. These equations are then secondly used to easily deduce the required linear dimensions of the current conduit by introducing a non-dimensional correction factor. The application of the obtained relationships requires only a strict minimum of data. All relationships provided in this article are applicable to the entire domain of the turbulent flow. Practical examples are taken to enable the hydraulic engineer to better understanding the advocated method and to observe the facility with which design of such a geometric profile can be performed.

Design of a Pressurized Circular Pipe with Benches Using the Rough Model Method (RMM)

2014 ◽  
Vol 960-961 ◽  
pp. 586-591
Author(s):  
Mohammed Riabi ◽  
Bachir Achour
Keyword(s):  
Turbulent Flow ◽  
Friction Factor ◽  
Correction Factor ◽  
Relative Roughness ◽  
Model Method ◽  
Linear Dimensions ◽  
Rough Model ◽  
Current Design ◽  
Basic Equations ◽  
Geometric Elements

The rough model method (RMM) is explained through its application to the design of a pressurized circular shaped conduit with benches, widely used in practice. The three basic equations of turbulent flow are firstly applied to define explicitly the geometric elements of a referential rough model characterized by an arbitrary assigned relative roughness value. The required linear dimensions of the studied conduit are then easily deduced by multiplying the homologues linear dimensions of the rough model by a non-dimensional correction factor. Friction factor is not indispensable when applying the RMM, unlike current design methods. Resulting RMM equations are not only explicit but are also valid in the entire domain of turbulent flow.

On the Calibration of Irwin Probes for Flow in Rectangular Ducts With Different Aspect Ratios

2017 ◽  
Vol 139 (10) ◽  
Author(s):  
Raquel Faria ◽  
Almerindo D. Ferreira ◽  
A. M. G. Lopes ◽  
Antonio C. M. Sousa
Keyword(s):  
Experimental Data ◽  
Friction Coefficient ◽  
Turbulent Flow ◽  
Flow Region ◽  
Reynolds Numbers ◽  
Hydraulic Diameter ◽  
Equivalent Diameter ◽  
Aspect Ratios ◽  
Cross Section Area ◽  
Section Area

In this work, the suitability of pressure probes, commonly known as Irwin probes, to determine the local wall shear stress was evaluated for steady turbulent flow in rectangular ducts. Pressure measurements were conducted in the fully developed flow region of the duct and both the influence of duct aspect ratio (AR) (from 1:1.03 to 1:4.00) and Reynolds number (from 104 to 9 × 104) on the mean characteristics of the flow were analyzed. In addition, the sensitivity of the longitudinal and transversal placement of the Irwin probes was verified. To determine the most appropriate representation of the experimental data, three different characteristic lengths (l*) to describe Darcy's friction coefficient were investigated, namely: hydraulic diameter (Dh), square root of the cross section area (√A), and laminar equivalent diameter (DL). The comparison of the present experimental data for the range of tested Re numbers against the results for turbulent flow in smooth circular tubes indicates similar trends independently of the AR. The selection of the appropriate l* to represent the friction coefficient was found to be dependent on the AR of the duct, and the three tested scales present similar performance. However, the hydraulic diameter, being the commonly employed to compute turbulent flow in rectangular ducts, is the selected characteristic length scale to be used in the present study. A power function-based calibration equation is proposed for the Irwin probes, which is valid for the range of ARs and Reynolds numbers tested.

scholarly journals Remote Laboratory for Measuring Linear Dimensions in the Process of E-Learning

2016 ◽  
Vol 12 (04) ◽  
pp. 43
Author(s):  
Jovan Šulc ◽  
Dragan Šešlija ◽  
Slobodan Dudić ◽  
Ivana Milenkovic
Keyword(s):  
Linear Dimension ◽  
Remote Access ◽  
Remote Laboratory ◽  
The Real ◽  
Linear Dimensions ◽  
E Learning ◽  
Set Up ◽  
Novi Sad ◽  
The University ◽  
And Control

Remote Laboratory for Measuring Linear Dimensions with remote access and control via Internet is developed and described in this paper. The system is realized at the University of Novi Sad, Faculty of Technical Sciences. This lab is dedicated to the students of secondary vocational schools and faculties with the aim to gain knowledge regarding linear dimension and mechanical component tolerance. Every user of this set-up is able to interact, observe and learn through the real measurement processes via communication infrastructure.

Sign in / Sign up

Export Citation Format

Share Document