It is the portion that lies in between the converging and diverging part of the venturi. A venturi is a convergingdiverging nozzle of circular crosssection. Several graphs demonstrating the varying relationships and. As liquid flows through the pipe, the flow suddenly contracts as it approaches the orifice and then suddenly expands after the orifice back to the full pipe diameter. Jun 05, 2018 venturimeter has high accuracy as compare to other flow measuring devices like orifice meter, pitot tube and nozzles. Flow through venturi meter background and theory introduction. Venturimeter principle, construction and working with diagram. Experimental and cfd analysis of flow through venturimeter. To find the coefficient of discharge for orifice meter. Venturi meter and orifice meter are the commonly used flow meters for measuring massvolumetric flow rate or velocity of the flowing fluid. Energy losses are less in a venturi meter whereas energy losses. Pdf using experimental curves for the discharge coefficients of venturimeter or orificemeter, the pipe discharge is obtained iteratively.
Advantages of venturimeter disadvantages of venturimeter. Venturi meter a cross section of the brass venturi meter tested is shown in figure 3. This also work on the same principle as that of venturimeter. Predictionof discharge coefficient of venturimeter at low. It can also be applied to real incompressible fluids with good results in. What is the difference between venturimeter and orificemeter. Application of orifice meter for accurate gas flow measurement techwpaper download as pdf file. An orifice meter consists of a flat plate that has a sharpedged hole accurately machined in it and placed concentrically in a pipe as shown in figure 12. Discharge coefficient performance of venturi, standard. However, the same principle can be exploited with only minimal pressure loss with the use of a venturi meter. If a pump forces the liquid through a tube connected to a system consisting of a venturi to increase the liquid speed the diameter decreases, a short piece of tube with a small hole in it, and last a venturi that decreases speed so the pipe gets wider again, the gas will be sucked in through the small hole because of changes in pressure. The venturi meter has a converging conical inlet, a cylindrical throat and a diverging recovery cone fig. Orifice meter presents a cheaper method to measure the rate of flow through the pipe.
Difference between venturi and orifice compare the. The expanding section of venturi meter returns the flow near to its original pressure. It consists of flat circular plate which has a circular hole, in concentric with the pipe. In this meter, the fluid is gradually accelerated to a throat and then gradually retarded in diverging section where the flow channel expands to the pipe size. Venturimeter and orificemeter apparatus make labtek, origin india piping system. Venturi meterconstruction, working, equation, application. A spreadsheet to assist with orificeventuriflow nozzle meter calculations and iso 5167 calculation of an orifice coefficient is also provided. Unlike the orifice meter, the fluid jet after passing through the restriction throat of venturi expands to a large area gradually. For measurement through venturi, open the outlet valve of the venturi meter. A target b venturi c orifice plate d pitot tube e turbine. In this post the effect of venturi meter and orifice plate on the fluid flow will be disciussed and complete work will be presented in the form of report. It works on the basic principle of bernoullis equation. An orifice meter is a conduit and a restriction to create a pressure drop. Experimental and cfd analysis of flow through venturimeter to.
Whereas the flow through venturimeter results into a pressure difference between the inlet and the throat, in the case of orificemeter there is a pres sure difference. Calibration of orifice flow meter and venturi flow meter d. Jan 24, 2018 for the love of physics walter lewin may 16, 2011 duration. The orifice meter valve is closed completely and for the venturimeter, the desired flow in supply and calibration line is achieved by control valves in supply line, calibration line and pump bypass line 4. The first recorded use of an orifice device for fluid measurement was in 1797 by giovanni b. Jun 01, 2018 orifice plate and orifice meter workingtypes of orifice plates flow measurement by orifice meter duration. Jun 24, 2016 a venturimeter is a device used for measuring the rate of flow of a fluid flowing through a pipe. Nov 20, 2016 venturi meter and orifice plate lab report venturi meter and orifice plate effects are two main and very important phenomenas in fuild mechanics sub field of mechanical engineering. Fundamentals of orifice meter measurement this white paper provides an overview of orifice meter technology, its advantages and general installation recommendations, as well as describes basic gas flow laws and the variables of orifice meter flow equations.
The standard orifice plate does not follow the general trend in the discharge coefficient curve that the other flow meters do. This implies that the curves accurately represent the data points. Note that there is provision for user input to select either u. Venturimeter consists of a converging portion, throat and a diverging portion. Venturimeter has high accuracy as compare to other flow measuring devices like orifice meter, pitot tube and nozzles.
In 1890, it has been reported that an orifice meter designed by professor s. Venturi meter and orifice meter dynamics mechanics civil. The cross section of the throat is much less than the cross. Venturimeter is the most widely used device to measure the discharge through the pipe. The size of the venturimeter is expressed in inlet and throat diameter form. Energy losses through venturi, orifice, and rotameter. All three use a constriction in the flow path like an orifice plate to cause a pressure drop across the meter that can be measured and correlated with flow rate. Determination of coefficient of discharge for venturimeter fluid practicals. It can be installed in any direction between pipe flow i. Calibration of an orifice plate flowmeter mechanical engineering department king saud university riyadh submitted by. It is a cheaper device as compared to venturimeter.
Pressure recovery is measured as the pressure difference between inlet and outlet. A free powerpoint ppt presentation displayed as a flash slide show on id. The main objectives of this experiment is to obtain. Like the venturi meter, the pressure difference varies directly with the flow rate. The project was on the construction of a venturi meter. In the previous programme we saw that the relationship between the pressure p, the velocity u and the elevation z of a flowing fluid is given by bernoullis.
To find the coefficient of discharge for venturi meter. Plot results from both flow rates on the same graph. The pressure difference between the upstream end if the cone and the throat are measured and provide the signal for the rate of flow. The theory is the same as for the orifice meter but a much higher proportion of the pressure drop is recoverable than is the case with orifice meters. Application of bernoullis law orifice meter venturi meter 6. Venturi meter is a device or component which is used for measuring the rate of flow of liquid through pipes. In simple language, this is defined as the sum of pressure energy, kinetic energy per unit volume and potential energy per unit volume equal in the same. Venturi meter, orifice meter, and pitot tube are widely used head flow meters in the industry. Venturi meter and orifice plate effects are two main and very important phenomenas in fuild mechanics sub field of mechanical engineering. In this meter the fluid is accelerated by its passage through a converging cone of angle 15.
It consists of flat circular plate which has a circular hole. A venturi can also be used to mix a liquid with a gas. To find the water flow rate using the venturi meter and the pressure distribution along the meter. Jul 08, 2015 application of bernoullis law orifice meter venturi meter 6.
A nozzle, venturi or thin sharp edged orifice can be used as the flow restriction. Both venturis and orifice plates are used in industrial applications and in scientific laboratories for measuring the flow rate of liquids. Venturimeter principle, construction and working with diagram june 24, 2016 march 4, 2018 pankaj mishra 0 comments fluid mechanics. A venturimeter is a device used for measuring the rate of flow of a fluid flowing through a pipe.
Fm 308 flow measurement by venturi and orifice meter. There are many different meters used to measure fluid flow. Venturi meter and orifice meter venturimeter in this meter the fluid is accelerated by its passage through a converging cone of angle 15, venturi meters are flow measurement instruments the venturi meter has an advantage over the orifice orifice plates, nozzles and venturi tubes inserted in. Pdf discharge equations for venturimeter and orificemeter.
One of the disadvantages of orifice meters is the large irreversible pressure loss across the orifice, which results in substantial pumping costs in case of large diameter pipes. Venturimeter can be used for the measurement of flow of water, liquids, gases, dirty liquids etc. Venturimeter principle, construction and working with. Jul 01, 2011 a venturi meter constricts the flow of fluid and the pressure differential is measure using pressure sensors before and within the constriction. A venturi meter is a variable head meter, which is used for measuring the flow rate of a fluid through a pipe.
See details of the equation that applies to all three and gives flow rate as a. To determine the coefficient of discharge of the orifice meter 1. In this post the effect of venturi meter and orifice plate on the fluid flow will be disciussed and. Head loss coefficient of orifice plate energy dissipator. A venturi meter constricts the flow of fluid and the pressure differential is measure using pressure sensors before and within the constriction. Apr 03, 2020 venturi meter is a device or component which is used for measuring the rate of flow of liquid through pipes. Venturi, an italian physicist whose work led to the development of the modern venturi meter in 1886 by clemons herschel. Schematic diagram for venturimeter and orifice meter a. Bsen 3310 lab 2calibration of orifice flow meter and. The major drawback of the venture meter is we cannot use it for small diameter size pipe. Pipe lines, each line fitted with a venture meter and orifice meter of size 25 mm with a gate valve and provided with a set of distribution chamber having isolating cocks to facilitate experiment on individual venture meter or orifice.
Introduction there are many different meters used to measure fluid flow. Determination of coefficient of discharge for venturimeter. In comparison of venturimeter with the orifice meter, the pressure recovery is much better for venturimeter than for the orifice plate, but there is no complete pressure recovery. Department of mechanical engineering venturi meter objective. Venturi meter and orifice meter venturimeter in this meter the fluid is accelerated by its passage through a converging cone of angle 1520o. The mass and volumetric flow rates did not differ by much, as seen on the graphs. Venturimeter has some disadvantages also like, it has high initial cost because its calculation is very complicated. Menentukan koefisien pengaliran pada alat venturimeter yang digunakan. As per iso 51671 3, the mass flow rate in a venturimeter q m is given by.
Venturi meter being a measuring instruction was used in determining the flow rate of fluid down a pipe or the rate of discharge in a pipeline and is often fixed permanently at different sections of the piple line to know the discharge there. In the previous programme we saw that the relationship between the pressure p, the velocity u and the elevation z of a flowing fluid is given by bernoullis equation. Fm 308 flow measurement by venturi and orifice meter objectives. Pipe flow measurement with a differential pressure flow meter. It is that portion of the venturi where the fluid gets converges. Venturi meters have only a small head loss, no moving parts. Venturimeter is used to measure the rate of flow through a pipe. Menunjukkan pengaruh perubahan penampang terhadap tinggi garis hidraulik pada masingmasing manometer. The venturi flow meter consists of a streamlined contraction and a streamline expansion as shown the diagram. Orifice plate is similar in the sense that it make use of a plate with a small hole in between to place restriction in the passage of the fluid. This is done by creating a smaller diameter at a certain point in the pipe. So this type of flow meter experiences lesser pressure drop as compared to that of the orifice. Bsen 3310 lab 2calibration of orifice flow meter and venturi.
Fm 308 flow measurement by venturi and orifice meter chemical. The venturi effect is the reduction in fluid pressure that results when a fluid flows through a. The orifice meter is constructed as shown in figure 5. Till abstract orifice and venturi flow meters decrease the pressure of a fluid by increasing its velocity as it flows through them. The main advantage of venturimeter is it has very less losses and high accuracy. Venturi meter and orifice meter free download as pdf file. It can also be applied to real incompressible fluids with good results in situations where frictional effect is very small. Venturimeter it is a device used for the measurement of flow in a pipeline. Venturi meter presents a costlier method to measure the rate flow of fluid through the pipe. In order to use any of these devices for measurement it is necessary to empirically calibrate them. Check whether the water level in the main tank is sufficient for the suction pipe of pump to be completely immersed. Flow measurementorifice meter fluid mechanics coursera.
The inlet section is a standard asme longradius nozzle with a throat diameter dv of 0. Discharge equations for venturimeter and orificemeter. A venturi meter can be used to measure the flow rates of all incompressible fluids gases with low pressure variations, as wells as liquids, whereas an orifice. The gradual approach to and the gradual exit from the orifice substantially eliminates boundary layer separation. A venturimeter is a device used for measuring the rate of a flow of a fluid flowing through a pipe. Readings taken are time taken for 100 mm rise in water level in the measuring tank. The fluid is then retarded in a cone of smaller angle 57o in which. Which of the following flowmeasuring elements is inherently linear and requires no signal characterization e. Objective the main objectives of this experiment is to obtain the coefficient of discharge from experimental data by utilizing venturi meter and, also the relationship between reynolds number and the coefficient of discharge. Energy losses through venturi, orifice, and rotameter flowmeters. That is, pass a known volume through the meter and. It uses the same principle as a venturi nozzle, namely bernoullis principle which states that there is a. This orifice plate creates a measurable pressure difference between its upstream and downstream sides.
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