Orifice plate flow meter construction and working principle. Flow meters are referred to by many names, such as flow gauge, flow indicator, liquid meter, flow rate sensor, etc. Jan 02, 2018 both are used to measure the flow rate of gases and liquids. The same principle applies no maer what percentage oxyg en you are giving venturi colour oxygen % low flow setting total gas delivered at low flow high flow setting total gas delivered at high flow 24 2 lmin 52 lmin 4 lmin 102 lmin 28 4 lmin 45 6 lmin 68 lmin 31 6 lmin 47 8 lmin 63 lmin. Its unit is gram per cubic meter gm3 relative humidity. In our lectures we mentioned about the venturi meter as a flow rate measurement device. Pdf experimental investigation of the installation effects. Use two large screwdrivers one to stick in the hole and one to pry up the outer edge. Flow through venturi meter background and theory introduction flow meters are used in the industry to measure the volumetric flow rate of fluids of the modern venturi meter in 1886 by clemons herschel. As the fluid velocity in the throat is increased there is a consequential drop in pressure. The system fits a special device expressly designed. Principle of venturimeter the working of venturimeter is based on the principle of bernoullis equation.
Venturi meter flow is measured using the differential pressure principle differential pressure integrated with time, so that it is used to any engineering parameters like flow rate. The principle of venture meter is firstly developed by g. Fm 308 flow measurement by venturi and orifice meter. It is a cheaper device as compared to venturimeter. They have been in common use for many years, especially in the water supply industry. It provides more exact measurement than for example the common pitot tube but it is intended rather for smaller flight velocities the speed of sound is reached in the thinner part at small velocities.
A venturi creates a constriction within a pipe classically an hourglass shape that varies the flow characteristics of a fluid either liquid or gas travelling through the tube. In venturi meter losses are less so coefficient of discharge is higher whereas in orifice meter due to no convergent and divergent cones there. The 8 points voc sampling system consists of two parts, namely. Workingtypes of orifice plates flow measurement by orifice meter in hindi scrap book lovers, bearing in mind you dependence a supplementary autograph album to read, find the flow measurement engineering handbook richard w miller here. Multiphase flow meter flowatch the pietro fiorentini multiphase and wet gas flow meters are non intrusive, inline systems providing real time measurement of oil, water and gas flow rates in the dispersed phase of the flow avoiding the use of large systems. 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.
The venturi effect is named after its discoverer, giovanni battista venturi. It mentions venturimeter advantages or benefits and venturimeter disadvantages or drawbacks. What are some industrial uses of venturi and orifice meters. It is defined as a ratio of moisture content of the gas to the maximum moisture the gas can contain at that temperature. Water at 50o f is flowing through a venturi meter with a 2 inch throat diameter, in a 4 inch diameter pipe. This page covers advantages and disadvantages of venturimeter. The orifice meter consists of a flat orifice plate with a circular hole drilled in it. As the fluid from the entry section of venturi meter flows into the converging section, its pressure keeps on reducing and attains a minimum value p2 when it enters the throat. Venturimeter principle, construction and working with. It is mainly used for robust applications as it is known for its durability and is very economical. Oct 03, 2015 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 classical venturi meter, whose use is described in iso. To find the water flow rate using the venturi meter and the pressure distribution along the meter. Inserttype venturi flow meter installation and operation manual.
This also work on the same principle as that of venturimeter. A venturi meter may also be used to increase the velocity of any type fluid in a pipe at any particular point. Italian scientist giovanni b venturi 17461822 was the first to observe. Venturi flow meter installation and operation manual. Venturi meter and orifice meter are the commonly used flow meters for measuring massvolumetric flow rate or velocity of the flowing fluid. Its basic principle is also depends on the bernoulli equation i. Does the sensing element of the meter contain moving parts that require periodic maintenance. Open channels, like rivers or streams, may be measured with flow meters. By reducing the crosssectional area of the flow passage, a pressure difference is created and the measurement of the pressure difference enables the estimation of the flow rate through the pipe. A flow meter is a device used to measure the volume or mass of a gas or liquid. No points venturi flow meter orifice plate meter 1 working principle works on venturi effect. Pdf split and merge tool is implemented using the pdfsharp library and is either gui or a free and open source software to merge, split, rotate and extract pages from pdf files.
There is a pressure tap upstream from the orifice plate and another just downstream. Being the system working with a principle where medical air under pressure goes released to the environment, the equipment has a high efficiency silencer reducing the noise to allow an adequate level of comfort for patients and operators. The venturi flow meter consists of a streamlined contraction and a streamline expansion as shown the diagram. Lift the lid just enough to slide it over to the side with. The working principle of orifice meter is the same, as that of venturi meter. Venturi meter is a device in which pressure energy is converted into kinetic energy and it used for measuring the flow rate discharge of the system. Fm 308 flow measurement by venturi and orifice meter objectives. It works on the basic principle of bernoullis equation. In simplest form, the pitot tube consists of a glass tube, bent at right. The total energy consists of pressure energy, kinetic energy and.
This pressure drop is measured using a differential pressure sensor and when calibrated this pressure becomes a measure of flow rate. This pressure drop is measured using a differential pressure sensor and when calibrated this pressure drop becomes a measure of flow rate. In 3 calibration of flow meter is done with the help of microcontrollers. A vortex flow meter is a flow measurement device best suited for flow measurements where the introduction of moving parts presents problems. Flow measurement options for october 20 pipeline and. An apparatus known as a venturi tube is the foundation for such device designs. These conservation theorems are collectively called. Middle east technical university department of mechanical. Information on the venturi coefficient will typically be provided by venturi meter manufacturers or vendors.
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. As the name implies, it consists of an orifice plate which is the basic. Connect the gas calibration cylinder to the calibration port. The flow measuring apparatus is used to familiarize the students with typical methods of flow. Ultrasonic flowmeters are commonly applied to measure the velocity of liquids that allow ultrasonic waves to pass, such as water, molten sulfur, cryogenic liquids, and chemicals. In venturi meter losses are less so coefficient of discharge is higher whereas in orifice meter due to. It states that in a steady, ideal flow of an incompressible fluid, the total energy at any point of the fluid is constant. An orifice meter is a flow meter used to measure the rate of flow of liquid or gas or steam using the differential pressure measurement principle. What is the working principle of orifice meter answers. Converging cone or diameter the area is decreasing throat diameter the area is constant. Venturi meter is a device or component which is used for measuring the rate of flow of liquid through pipes. Basic principle of orifice meter when an orifice plate is placed in a pipe carrying the fluid whose rate of flow is.
When fluid passes through orifice, there is large drop in pressure that is indicative of flow rate 2 construction it has the. Principles of the anesthetic machine patterson scientific. Venturi flow meter installation and operation manual designs, materials, weights and performance ratings are approximate and subject to change without notice. With no moving parts or abrupt flow restrictions, the venturi can measure fluid flowrates with a minimal total pressure loss. Venturi flow meter working principle animation when a venturi flow meter is placed in a pipe carrying the fluid whose flow rate is to be measured, a pressure drop occurs between the entrance and throat of the venturi meter. Venturimeter principle, construction and working with diagram. The venturimeter is a instrument or device used to measure discharge through a pipe. If the velocity at any point decreases, the pressure at that point increases due to the conservation of the kinetic energy into pressure energy. Apr 26, 2015 15 venturi meter vs flow when a venturimeter is placed in a pipe carrying the fluid whose flow rate is to be measured, a pressure drop occurs between the entrance and throat of the venturimeter.
Venturi meter is a device used to measure the flow rate or discharge of fluid through a pipe. To find the coefficient of discharge for orifice meter. To find the coefficient of discharge for venturi meter. Venturimeter is an application of bernoullis equation. Experimental investigation of the installation effects on the venturi flow meter performance conference paper pdf available june 2000 with 2,477 reads how we measure reads. Application note 237 multipoint voc measurement system. Venturi meterconstruction, working, equation, application. Venturi meters are flow measurement instruments which use a converging section of pipe to give an increase in the flow velocity and a corresponding pressure drop from which the flowrate can be deduced. The venturi effect is the reduction in fluid pressure that results when a fluid flows through a constricted section or choke of a pipe. Jun 24, 2016 the working of venturimeter is based on the principle of bernoullis equation. They are available in industrial grade, brass or all plastic construction. It consists of flat circular plate which has a circular hole, in concentric with the pipe.
This principle states that within a specified flow field, a decrease in pressure occurs when there is an increase in velocity. Be careful because fluids that do not pass ultrasonic energy, such as many types of slurry. Jul 03, 2018 construction and working principle of orifice plate flow meter video lecture of flow measurement transducers chapter in subject electronic instrumentation and measurement for electrical. Construction and working principle of orifice plate flow meter video lecture of flow measurement transducers chapter in subject electronic instrumentation and measurement for electrical. In venturi, pressure energy pe converted into kinetic energy ke to calculate flow rate discharge in a closed pipeline. Figure 2 shows an orifice meter with the variable position of vena contracta with respect to the orifice plate. Department of mechanical engineering venturi meter objective. A venturi meter is also called a venturi flowmeter. Discuss the principle and operation of cyclone separator. This pressure drop is measured using a differential pressure sensor and when calibrated this.
The fluid whose flow rate is to be measured enters the entry section of the venturi meter with a pressure p1. Venturi pattern provides optimized approach and discharge angles, plus smooth flow contours to provide minimum pressure drop. Due to its simplicity and dependability, the venturi is among the most common flowmeters. The differential producing flowmeter or venturi has a long history of uses in many applications. The pressure difference described by the venturi effect is utilized in many different devices. Measuring principle pressure absolutegauge pressure, differential pressure, hydrostatic pressure. Of course, if the instrument were static with respect to flowing fluid, it would have move along with the fluid. The total energy consists of pressure energy, kinetic energy and potential energy or datum energy. A major disadvantage of the venturi nozzle is that it is more difficult to replace than the orifice unless it can be removed as part of a spool section. In practise the venturi tube is used in planes to measure the flight velocity. Mar 18, 2010 what is the working principle of orifice meter. So this device is placed in the pipe for which discharge is to be calculated.
The basic principle of the nordstrom valve pascals principle. Advantages of venturimeter disadvantages of venturimeter. Static, stagnation, and dynamic pressures bernoulli equation is in this equation p is called static pressure, because it is the pressure that would be measured by an instrument that is static with respect to the fluid. Venturi is an example for restriction type flow meter. In this post, i am interested in covering the details about how to measure flow using orifice meter. With the measuring principle pressure process pressure, differential pressure, level and flow. Flow measurement engineering handbook richard w miller. Operating principle the series balancing valve is a hydraulic device that controls. It basically works on the principle of bernoullis theorem. Oct 19, 2015 this principle states that within a specified flow field, a decrease in pressure occurs when there is an increase in velocity.
Locate the water meter on your property, usually located in a concrete box near the street labeled ccwd. An intelligent flow measuring technique using venturi. Venturi effect using compressed air as its power source, and a blowback system red dotted line in figure 3. Differential pressure type flow meters head flow metersmeasure flow rate by introducing a constriction in the flow.
Construction details venturi flow rate measurement device as shown in the. The anesthetic machine dispenses the gases that are necessary to induce sleep and prevent pain to animals during surgical procedures or other potentially painful manipulations. The flow nozzle, like the venturi meter, has a greater flow capacity than the orifice plate and requires a lower initial investment than a venturi tube, but also provides less pressure recovery. Flow through venturi meter background and theory introduction flow meters are used in the industry to measure the volumetric flow rate of fluids. The working of venturimeter is based on the principle of bernoullis equation. The meter consists of a pipe with a narrowing throat that expands back to its original diameter on the other side of the choke point. The manufacture of mass products has shifted to locations where.
Inserttype venturi flow meter installation and operation manual designs, materials, weights and performance ratings are approximate and subject to change without notice. Looking for downloadable 3d printing models, designs, and cad files. The venturi effect is the reduction in fluid pressure that results when a fluid flows through a constricted section of pipe. Transit time designs are also available to measure gas and vapor flow. The basic anesthetic delivery system consists of a source of oxygen. The frequency of the vortices is directly proportional to the velocity of the fluid. Flow nozzle principle when a flow nozzle is placed in a pipe carrying whose rate of flow is to be measured, the flow nozzle causes a pressure drop which varies with the flow rate. Flow measurement in pipes and ducts ced engineering. Construction and specification of venturi meter venturi is an example for restriction type flow meter. Sluice gate and weir are also flow measurement devices and their working principle can be studied.
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