Flumes

Flow meters have traditionally been classified as either electrical or mechanical depending on the nature of the output signal, power requirements, or both. However, improvement in electrical transducer technology has blurred the distinction between these categories. Many flow meters previously classified as mechanical are now used with electrical transducers. Some common examples are the electrical shaft encoders on positive displacement meters, the electrical (strain) sensing of differential pressure, and the ultrasonic sensing of weir or flume levels. 

Fig. 11. The ParshaH flume showing (a) flume constmction and (b) stream flow (9).

A number of flume designs have been created specifically for use in partially fiUed circular conduits such as sewers. These are available in molded fiber glass and can be lowered through a manhole if required. As with all open-channel head-area meters, flumes must be sized to prevent submergence of the restriction. 

Eiquid Flow Measurement in Open Channels Using Thin Plate Weirs and Venturi Flumes, ISO 1438-1975(E), International Organization for Standardization, Geneva, Switzerland, 1975. 

FIG. 12-14 Sizing chart for a coiinterflow induced-draft cooling tower, for induced-draft towers with (1) an iipspray distributing system with 24 ft of fill or (2) a flume-type distributing system and 32 ft of fill. The chart will give approximations for towers of any height. (Ecodyne Carp.)... 

The wastewater enters the plant through the headworks where it passes through a bar screen, comminutor and Parshal flume. Following the headworks, the wastewater enters the aeration basin where floating surface aerator aerate and mix... 

Seebeck, Thomas Johann (1770-1831) Barbara Flume-Gorezyea... 

Data after Fontana and Greene source International Nickel Co. t Immersed in tidal current. t Immersed in sea-water flume. 

Baonold, R. A. Proc. Inst. Civ. Eng. (iii) 4 (1955) 174. Some flume experiments on large grains but little denser than the transporting fluid, and their implications. 

An open concrete flume is to be constructed to carry water from a plant unit to a cooling lake by gravity flow. The flume has a square cross section and is 1500 ft long. The elevation at the upstream end is 10 ft higher than that of the lower end. If the flume is to be designed to carry 10,000 gpm of water when full, what should its size (i.e., width) be Assume rough cast concrete. 

Data from B. Lewis and G. von Elbe, Combustion, Flumes and Explosions of Gases (New York Harcourt Brace Jovanovich, 1987). 

Most of the Amazon Basin is made up of alluvial deposits from the Andes. La Chorrera is different. A river, the Rio Igara-Parana, narrows and flows into a crack. It becomes very rapid then drops over an edge—a lip—creating not exactly a waterfall but a narrow channel of water (chorro means "chute"), a flume whose violent outpouring has made a sizable lake. 

This Silurian Group (418-424 Ma) has two formations associated with the Harvey area, Burtts Corner Formation and Flume Ridge formation, both consisting... 

Flume L, Di Stefano G, Bus C, Mattioli A, Bonino F, Torrani-Cerenzia M, Verme G, Rapicetta M, Bertini M, Gervasi GB,/. Viral Hepat. 1997,4,363-370. 

Open-Channel Flow Measurement Open-channel flow measurements are usually based on measurement of liquid level in a flow channel constructed of a specified geometry. The two most common flow channels used are weirs and flumes. See Spitzer (2005, op. cit.). 

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