However, for smaller pipes orifice meter is a suitable choice. Each meter works by its ability to alter a certain physical property of the flowing fluid and then allows this alteration to be measured. The reduction of the cross section of the flowing stream in passing through the orifice. Orifice ports are accurately machin ed f or precision measur ements. An orifice meter is a conduit and a restriction to create a pressure drop. The volumetric flowrate, q, of a given fluid through an orifice nozzle flow meter is proportional to the square root of the pressure drop across the meter. Energy losses through venturi, orifice, and rotameter flowmeters.
An orifice meter is a piece of equipment used to measure the flow rate of a gas or a fluid. To find the coefficient of discharge for venturi meter. Several graphs demonstrating the varying relationships and. I have this misconception about pressure drop of venturi meter and orifice meter. The term orifice meter is used to mean everything from the orifice meter chart recorder to the entire meter station. The discharge will depend up on the head of the fluid h above the level of the orifice. Meters should have at least 10 pipe diameters of smooth, clean, straight pipe upstream and downstream for accurate readings. Like the venturi meter, the pressure difference varies directly with the flow rate. The orifice plate flow meter is commonly used in clean liquid, gas, and steam services. By employing the continuity equation and bernoullis principle, the volumetric flow rate through the orifice meter can be calculated as described previously for venturi meter. Either a volumetric or mass flow rate may be inferred with an orifice meter depending on the calculation associated with the orifice plate. Daniel measurement and control white papersfundamentals of orifice meter measurement page 1 fluid meters are divided into two functional groups one measures quantity positive displacement.
The orifice plate is also approved by many organizations for custody transfer of liquids and gases. It is typically made of carbon steel, and the main components of the device are. Fluid meters in incompressible flow fluid mechanics. Wallaces hints regarding common strengths and weakness of each section of a lab report a sample cover memo. What is the difference between venturimeter and orificemeter. Effects of beta ratio and reynolds number on coefficient of discharge of orifice meter c d depends on the ratio of orifice to pipe diameter called beta ratio. The venturitube has a converging conical inlet, a cylindrical throat, and a. Flow through venturi meter background and theory introduction. Position the water flow measuring apparatus on the horizontal operating surface of the hydraulics bench 2. Comparative study on orifice versus turbine meter for. Orifice meter the venturi meter described earlier is a reliable flow measuring device. This orifice plate creates a measurable pressure difference between its upstream and downstream sides. To determine the minor head loss coefficient for different pipe fittings.
Effects of beta ratio and reynolds number on coefficient of. The principle of the orifice meter is identical with that of the venturi meter. Orifice meter flow measurement fluid mechanics scribd. It uses bernoullis principle which states that there is a relationship between the pressure of the fluid and the velocity of the fluid.
Investigation of flow through the twostage orifice. An annotated sample lab report prepared on a fluids experiment. To determine the coefficient of discharge of orifice meter. As the flow area in a pipe decreases, the flow velocity that is accompanied by a decrease in pressure increases in a pipe. Pdf experimental investigation of the installation effects on the. Fluid flow is an important part of many processes, including transporting materials from one point to another, mixing of materials, and chemical reactions. Water flow measuring apparatus is designed as a freestanding apparatus for use on the hydraulics bench, although it could be used in conjunction with a low pressure water supply controlled by a valve and a discharge to drain. 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.
One type of flow meter is the venture meter, as seen in figure 1. Shashi menon, in transmission pipeline calculations and simulations manual, 2015. Pdf the sensitivity of flow meters to their operational conditions continues to be a source of concern to. Ce 321 sample laboratory report packet this packet contains the following materials to help you prepare your lab reports in ce 321. The orifice meter, sometimes also called a head loss flow meter, is chosen most frequently because of its long history of use in many applications, versatility, and low cost, as compared to other available flow meter types. More specifically, this simple venturi meter, constructed from materials available at a local hardwareauto parts store, was characterized by determining the venturi coefficient and the permanent pressure loss.
Highlights flow features of an orifice meter have been simulated using cfd. The measured alteration is then related to the flow. It consists of an orifice plate which is the basic element of the instrument. Venturi meter and orifice plate effects are two main and very important phenomenas in fuild mechanics sub field of mechanical engineering. To determine the coefficient of discharge of the orifice meter 1. It is used for robust applications as it is known for its durability and is economical. Enlargement, thenventuri meter, orifice plate, elbow, and finally rotameter. Bsen 3310 lab 2calibration of orifice flow meter and venturi. Gaskets are provided to seal both sides of the plate.
Comparative study on orifice versus turbine meter for gas flow. Each orifice plate has model number and orifice diameter stamped on tab for easy identification and selection. Nov 19, 2007 venturi meter vs orifice meter posted in student. As the gas flows through an orifice meter is the gas being measured correctly. An orifice meter is basically a type of flow meter used to measure the rate of flow of liquid or gas, especially steam, using the differential pressure measurement principle. The orifice meter valve is closed completely and for the. Orifice plate, a restriction used to measure flow or to control pressure or flow, sometimes given specialised names. Stockham northrop grumman information technology major dirk plante defense threat reduction agency dtra if flow through an orifice s minimum area is maintained at mach 1, the volume flow rate is only a function of the temperature and the pr essure upstream of the orifice. Cfd is proposed as a cost effective tool to estimate discharge coefficient c d. Department of mechanical engineering calibration of an orifice meter objective. The major objective of this experiment was to construct, test and model a simple, inexpensive venturi meter. It is a cheaper device as compared to venturimeter.
Ansery orifice meter it may be installed in pipeline with a minimum of trouble and expense orifice meter orifice meter. Figure of orifice meter for lab test figure of orifice meter in field orifice plates and flanges description of orifice meter the main parts of an orifice flow meter are as follows. It is that portion of the venturi where the fluid gets converges. In this experiment, you will investigate fluid flow in a pipe network and will explore several methods rotameter, orifice and venturi meters for measurement of the fluid flow rate. Calibration of an orifice meter as you requested in your email of 080703, i have attached a copy of my final report on the calibration of an orifice meter experiment. Pdf flow through a venturi meter orifice rotameter. What is the difference between flow coefficient and discharge coefficient for a needle valve. Venturi and orificemeters are the most commonly used nowsensing elements in. Pdf design and validation of a calibrated orifice meter for sub500. In order to use any of these devices for measurement it is necessary to empirically calibrate them. The great thing that often gets forgotten with orifice plates and other dp devices, is that they are manufactured to suit a specific flow.
An orifice is an opening in the side or base of tank or reservoir through which fluid is discharge in the form of a jet. Orifice meter, installed on different pipes, arrangement of varying flow rate, u tube manometer, collecting tube tank, vernier calliper tube etc. Body orifice, any opening in the body of a human or animal. To determine the coefficient of discharge c d, velocity c v, and contraction c c of various types of orifices 2. The water flow rate can be adjusted using the valves on the hydraulics bench. An introduction to an orifice meter 909 words bartleby. Materials and methods a manometer figure 1, an orifice flow meter figure 2, and a venturi flow meter figure 3 were used to measure the flow rate and pressure change of. 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. Box 2481 tulsa, ok 74101 what is an orifice recorder. To determine the coefficient of discharge of an orifice meter.
Figure 2 shows an orifice meter with the variable position of vena contracta with respect to the orifice plate. The standard deviation, for cd was also calculated to be. To find the coefficient of discharge for vcnturi meter. Critical orifice theory, design and implementation dr leo w.
Pdf experimental investigation of the installation effects. Introduction an orifice meter is a type of flow meter used to measure the rate of flow of liquid in form of steam, using the differential pressure measurement principle. Combining equations and 14 we obtain the relationship. All fluid meters, however, consist of two distinct parts, each of which has different functions to perform. Bacalso avenue, cebu city chemical engineeing department final report che lab 1 title of experiment juphil a. Model 5 720 calibrated orifice flow meters are desig ned for measurin g flows of air or g ases at pressures up to 100 psig and temperatures to 700 of. The orifice meter, the nozzle meter, and the venturi meter are the most common devices used to measure the instantaneous flowrate. I will be using a needle valve for my practical setup of project work. Thus, qk h where is the meter calibration constant and is the manometer reading that. Effects of entrained liquid on orifice measurements william johansen colorado engineering experiment station, inc.
Venturi meter, orifice meter, and pitot tube are widely used head flow meters in the industry. Compared with other head meters, such as the venturi meter and the nozzle, the orifice meter is less expensive to fabricate and install. I have read about pressure recovery for both meters and found that there is always a permanent pressurehead loss dependent on the area ratio for orifice while for venturi, fluid slows down in a cone with smaller angle where kinetic energy is converted back to. Nov 26, 2009 for the love of physics walter lewin may 16, 2011 duration. The liquid may be water, hydrocarbons, or compressor oil. With an orifice meter, the orifice together with the adjacent part of the pipe and the pressure connections constitute the primary element. Orifice metering satisfies most flow measurement applications and is the most common flow meter in use today. The answer usually depends upon who is providing the response. It consists of flat circular plate which has a circular hole, in concentric with the pipe. Orifice meter maintenance consists of periodic inspection as indicated above. There are many different meters used to measure fluid flow.
For measuring flow in enclosed ducts or channels, the venturi meter and orifice meters are more convenient and more frequently used. The orifice meter consists of a flat orifice plate with a circular hole drilled in it. A scheme has been proposed to position pressure tap at venacontracta to measure flow with better accuracy and sensitivity. It is available for all pipe sizes but it is very costeffective for measuring flows in larger ones over 6 diameter. What is the difference between flow coefficient and. Flow measurement by venturi and orifice meters objectives. It is working at variable pressure drop, which is caused by an area. Orifice meter merchant institute of technology,piludara prepared by. Orifice flow meter s are ideal for measuring air and gas flows in combustion systems. Sep 08, 2018 venturi meter presents a costlier method to measure the rate flow of fluid through the pipe. Conclusion in this experiment cd the coefficient of. The second manifold contains a straingauge pressure transducer and a stainless steel tank, which can be pressurized and subsequently bled via a.
So while some people get hung up on limited turndown they forget to tell the customer that the turndown is real and not a function of a theoretical meter full scale. The orifice meter, sometimes called the head loss flow. A schematic of the venturi meter is shown on the diagram at the end of the procedure. This also work on the same principle as that of venturimeter. Introduction there are many different meters used to measure fluid flow. An orifice is any opening, mouth, hole or vent, as in a pipe, a plate, or a body. The standard orifice plate does not follow the general trend in the discharge coefficient curve that the other flow meters do.
Flow meters are used in pipe flow scenarios to adjust particular physical characteristics of the fluid flow and enable for the measurement of the adjustment. Fundamentals of orifice metering smith metering, inc throughout the oil and gas industry, there stems the need for accurate, economical measurement of process fluids. Each of these meters operates on the similar principle. The measuring error of the flow sensor used in the experiment is approximately. Orifice meter presents a cheaper method to measure the rate of flow through the pipe. When comparing the reynolds number to cd for the venturi meter the graph remained relatively linear until there. Fm 308 flow measurement by venturi and orifice meter objectives. The pitot static is often used for measuring the local velocity in pipes or ducts. Fluid mechanics lab me 216 f list of experiments 1. That is, pass a known volume through the meter and note the reading in order to. A simple, inexpensive venturi experiment applying the.
Venturimeter in a venturi meter there is first a converging section in which the cross sectional area for flow is reduced. The pressure along the meter is obtained using the 11 pressure taps at the locations shown on the diagram. The orifice meter is constructed as shown in figure 5. Experimental and cfd analysis of flow through venturimeter. Flow through venturi meter background and theory introduction flow meters are used in the industry to measure the volumetric flow rate of fluids. 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. Periodically the master meter is returned to a standards lab or to the manufacturer for recertification. The secondary element consists of a differential pressure device together with a mechanism that translates the pressure difference into a rate of flow and indicates the result. Energy losses through venturi, orifice, and rotameter. It can also be applied to real incompressible fluids with good results in situations where frictional effect is very small. Conclusion in this experiment cd, the coefficient of discharge, was calculated for the venturi meter. Experimental investigation of the installation effects on the venturi flow meter performance conference paper pdf available june 2000 with 2,456 reads how we measure reads. Discharge coefficient performance of venturi, standard.
A venturimeter is a device used for measuring the rate of a flow of a fluid flowing through a pipe. Introduction throughout the oil and gas industry, there stems the need for accurate and economical measurement of process fluids and natural gas. Fm 308 flow measurement by venturi and orifice meter. For these reasons it is widely used, particularly for large volume liquid and gas flows. If the velocity at any point decreases, the pressure at that point increases due to the conservation of the kinetic energy into pressure energy. There is a pressure tap upstream from the orifice plate and another just downstream. A free powerpoint ppt presentation displayed as a flash slide show on id. Chapter 12 fluid mechanics university of minnesota duluth. To find the coefficient of discharge for oririce meter. A nozzle, venturi or thin sharp edged orifice can be used as the flow restriction.
Venturi meter and orifice meter are the commonly used flow meters for measuring massvolumetric flow rate or velocity of the flowing fluid. A simple sharpedged orifice demonstration for the fluid. The inlet diameter equals d 26 mm and the throat diameter d 16 mm. Cd for the venturi meter decreased as the flow rate decreased with each trial. Switch the pump on, allow the water to enter the flow measurement instruments,which are connected to manometers tubes. Determination of coefficient of discharge for venturimeter. The differential pressure flow measuring principle orifice. To find the coefficient of discharge for orifice meter. To determine the coefficient of discharge of the venturimeter 2. A stainless steel orifice plate which is held between flanges of a pipe carrying the fluid whose flow rate is being measured. In simplest form, the pitot tube consists of a glass tube, bent at right. Differential pressure type flow meters head flow metersmeasure flow rate by introducing a constriction in the flow. It mainly consists of an orifice plate, an orifice plate housing, and a meter tube. Water flow measuring apparatus is designed as a freestanding apparatus for use on the hydraulics bench, although it could be used in conjunction with a low pressure water supply controlled by a valve and a.
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