Flume, boundary layer, venturi flume, palmerbowlus flume. The venturi effect is named after its discoverer, giovanni battista venturi. Weirs and flumes flow measurement instrumentationtools. At critical flow further reduction in the width of the flume throat wouldnt lower the depth of flow. Derive equations for the flow rate through a venturi flume. Get access to read online pdf ebook library lab manual of venturi flume experiment download lab manual of venturi flume experiment. This flume is a modification of parshalls original design but is more portable and convenient to use as it consists only of the converging section and throat section. A pair of venturi sides to fit into the channel allowing demonstrations of flow measurement techniques used in rivers and waterways. For submergedflow measurement, water levels both upstream and at the throat section must be known. Hd 1 r1 civil engineering lab iigroup 3 hydraulics 1 hd 1.
The armfield multi purpose teaching flume has been developed to assist students to overcome this difficulty. There are two conditions of flow that can occur in a parshall flume. Hd 1 r1 civil engineering lab iigroup 3 hydraulics 1. Flow measurement ii hydromechanics vvr090 flow measurements in flumes use of flumes might be preferrable to measure flow rate compared to weirs. This thesis is brought to you for free and open access by. Flow through venturi meter background and theory introduction flow meters are used in the industry to measure the volumetric flow rate of fluids. Fluid mechanics module 4 venturi meter lecture 28 youtube.
For a parshall flume to operate under free flow conditions, the downstream channel must be of a sufficient size configuration so that flow does not back up into the flume slowing discharge out of the flume. Structural analysis vol 2 by bhavikatti pdf 28 download. Lab manual of venturi flume proton service manual download ncert lab manual of science for class 10. Venturi flume experiment fluid mechanics flow measurement. Water flow measuring apparatus is designed as a free standing apparatus for use on the hydraulics bench, although it could be used in conjunction with a low pressure water supply controlled by a. Venturi flume experiment free download as word doc. Broad crested weirventuriflume almost same procedure the chairman lukongo ngenge. Differential pressure type flow meters head flow metersmeasure flow rate by introducing a constriction in the flow. Broad crested weirventuriflume almost same procedure. Nov 27, 2016 broad crested weirventuriflume almost same procedure the chairman lukongo ngenge. The agricultural experiment station of the colorado agricultural college the venturi flume by ralph l. Venturi flumes are designed to accurately measure higher flow rates in open channels they work by being a particular shape that restricts the flow of water in such a way that it creates an accurate point for measurement where the flow is forced to reach a subcritical state. The main objectives of this experiment is to obtain. Hydraulic characteristics in the movable venturi flume with.
Venturi flume experiment theory a venture flume is a structure designed to achieve critical flow by constricting the width of the channel. Laboratory tests were performed using a longthroated flume installed in series with, but downstream from a venturi flume. The first one requires and the second approach does not require crossing of critical depth by the liquid free surface somewhere in a flume. Discharge coefficient performance of venturi, standard. A venturi flume is a criticalflow flume, wherein the critical depth is created by a local. File type pdf lab manual of venturi flume experiment lab manual of venturi flume experiment if you ally infatuation such a referred lab manual of venturi flume experiment book that will provide you worth, acquire the definitely best seller from us currently from several preferred authors. Open channel flow rate measurement is usually done by measuring a change in water depth. Furthermore, detailed experimental studies 21,22 have shown that the. Lab manual of venturi flume experiment pdf get access to read online pdf ebook library lab manual of venturi.
The major objective of this experiment was to construct, test and model a simple, inexpensive venturi meter. Parshall, senior irrigation engineer carl rowher, irrigation engineer irrigation division, bureau of public roads u. Theory supercritical flow, subcritical flow, and critical flow are the. A venturi flume is a criticalflow open flume with a constricted flow which causes a drop in the hydraulic grade line, creating a critical depth it is used in flow measurement of very large flow rates, usually given in millions of cubic units. Common types are the sharp crested weir including vnotch weir, rectangular weir, and cipolletti weir, the broad crested weir, the parshall flume and venturi flume. A venturi meter would normally measure in millimetres, whereas a venturi flume measures in metres. In order to maintain the measuring uncertainty as low as possible, an ultrasonic sensor with a very low dead zone type pm3, dead zone 0. The free flow discharge can be expressed as follows reference. Charateristics of flow through a venturi flume objective the purpose of this experiment is to determine the relationship between upstream head and flow rate for water flowing through a venture flume and determine the discharge coefficient and observe the flow patterns.
The obstruction caused to the flow of liquid at the throat of the venturi produces a local pressure drop in the. A type of open flume with a contracted throat that causes a drop in the hydraulic gradeline. From to i determination of chezys and mannings constants 3 5 ii determination of coefficient of discharge for venturi flume standing wave flume 6 8 iii determination of pipe friction factor. Civil engineering lab ii group 3 hydraulics 1 hd 1. Venturiflume 1 venturiflume it is a devise used to measure the discharge in an open channel. Pdf venturi flume is a very popular flow measuring device. The experiments indicate that the venturi flume will be free from interference due. A venturi meter would normally measure in millimeters, whereas a venturi flume measures. Such obstructions make the use of the ordinary rating flume very troublesome, if not quite.
Figure shows the plan and elevation of a venturiflume. The venturi flume can deliver a good example of this case sawicki 2001, polak 2005 in order to obtain the equivalence of calculated eq. Mar 01, 2018 structural analysis vol 2 by bhavikatti pdf 28 download. Q c h n where, q flow rate c free flow coefficient of flume h head at primary point of measurement n depends on flume size it is 1. Advantages of venturi flume,disadvantages of venturi flume. Venturi flumes both of which had sizeable shortcomings. Gunt experimental flumes have a rectangular crosssection. 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 is used in flow measurement of very large flow rates, usually given in millions of cubic units.
Flow measurement with long throated flumes under uncertain. Charateristics of flow through a venturi flume objective the purpose of this experiment is. Following are the benefits or advantages of venturi flume. Ppt venturiflume powerpoint presentation free to view.
A simple, inexpensive venturi experiment applying the. When studying hydraulics, the fundamental concepts of energy and momentum are sometimes difficult to grasp, particularly where free surface flow is concerned. The venturi effect is the reduction in fluid pressure that results when a fluid flows through a constricted section or choke of a pipe. The specific hydraulic model that we are concerned with for this experiment is the flow meter test rig, f121. Venturimeter are used to measure the velocity of flow of fluids in a pipe. When flow out of the parshall flume is returning to a channel or pipe, the epa.
From consideration of continuity between the mouth of the venturi of area a 1 and the throat of area a 2. The venturi effect is achieved by way of a horizontal constriction of the. Notable factors in comparing application of the venturi solution to a pipe meter with using the venturi solution on a longthroated flume are the magnitude of head differential observed as flow moves from the approach section, then is accelerated through the constricted throat sections. Two different approaches to flow rate measurements by flumes have been compared. Parshall flume wikipedia, the free encyclopedia the parshall flume acts essentially of reclamations water measurement manual in 1931 and published under venturi flume. This tutorial is a continuation of tutorial 1 and 2 and these should be studied first. A numerical study on curvilinear free surface flows in venturi. Free flow occurs in a flume when there is insufficient backwater to reduce the discharge through the flume. Measuring open channel flow rates with a weir or a flume. Cee 341 fluid mechanics for civil engineers lab manual. The headdischarge relationship of such measurement devices can be determined following the critical flow theory, but this approach is only valid if the length of the throat is sufficiently long. A venturi flume is a criticalflow open flume with a constricted flow which causes a drop in the. Broad crested weirventuriflume almost same procedure youtube.
This consists of a venturi meter, a variable area meter and an orifice plate installed in a series configuration to allow for direct comparison. A qh related ultrasonic volume measurement type nivumaster has been installed. Pdf hydraulic investigation of venturi flumes researchgate. It is designed in such a way that the velocity at the throat is less than the critical velocity so that no standing wave will occur in the flume. A plan view of venturi or parshall flume, b side view of a parshall flume 1 narrowest. Venturi flume for measuring water in open channels, in order that those in. They consist of short length of pipe shaped like vena contracta, or the portion with the least cross sectional area, which fits into a normal pipeline. Venturi flumes are recommended for liquid flow measurement within open channels, particularly where suspended solids material is being transported, and are almost universally used in measuring the inflow to sewage trea.
Applying bernoullis theorem to the venturi meter between section 1 and section 2. Jul 23, 2018 subject fluid mechanics topic module 4 venturi meter lecture 28 faculty venugopal sharma gate academy plus is an effort to initiate free online digital resources for the first time. It should be noticed that the validity of the numerical model is questionable for the. The improved venturi flume, under certain conditions of flow, does not operate according to the venturi principle but more nearly according to the principle of discharge over a weir, however, as explained later, if the flow is submerged, the device operates in accordance with the venturi principle. 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. It is used in flow measurements of very large flow rates.
A venturi flume is a criticalflow flume, wherein the critical depth is. The unit is designed for installation in the modular flow channel hm162. Download file pdf lab manual of venturi flume experiment the venturi flume hm162. Venturi flumes are used in openchannels to determine the discharge by the measurement of a water level. Without his hard work and continued dedication to the undergraduate experience at arizona state university, the hydraulics. The venturi measuring unit is designated below as the venturi channel meter, in order to clearly distinguish it from the venturi pipe meter.
Bibliomania gives readers over 2,000 free classics, including literature book notes, author bios, book. A control flume that comprises a short constricted section followed by one expanding to normal width. The experiments indicate that the venturi flume will be free from interference due to changes in the. Starting in 1915 with the subcritical venturi flume, dr. One of the most common flume design is the parshall flume, named after its inventor r. Critical flow occurs in the flume throat followed by a. Department of agriculture this bulletin is based on experiments conducted in. Hydraulic characteristics in the movable venturi flume. Nov 20, 2016 venturi meter and orifice plate effects are two main and very important phenomenas in fuild mechanics sub field of mechanical engineering. At critical flow further reduction in the width of the flume. The experiments indicate that the venturi flume will be free. To determine the theoretical discharge of the flume at free flow and. Notation h total head h water depth z s water surface level b channel width q discharge q qb discharge per unit width v velocity fr froude number measurements openchannel flow simulations are conducted in the armfield c4mkii.
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