![]() The discharge section (light blue) slows the now energetic super-critical flow and transitions it into the downstream channel.The throat (gray) of the flume accelerates the flow to a critical / super-critical state.It is here that the point of measurement (H a) is located. Flow in the converging section must enter at a sub-critical state. ![]() Flow is restricted in the converging section (dark blue) and is accelerated as it passes into the throat.Most flume styles consist of three parts: a converging section (inlet), a throat, and a discharge section (outlet). Less head loss (~1/4 th that of a weir)Īlso, most flumes are resistant to changes or restrictions in the downstream hydraulics (submergence) - something not found with weirs.The ability to measure higher flow rates than a comparably sized weir.While having similar accuracy, flumes have distinct advantages over weirs, including: This accuracy is similar to that of weirs - although weirs are slightly more accurate under ideal conditions. With proper installation, flumes can be accurate to +/-2-5% (for the flume itself) however, overall system accuracy is +/-10% when all factors are considered. ![]() The relationship between the water level at the point of measurement (H a) and the flow rate can be obtained by test data ( short-throated flumes) or derived formula ( long-throated flumes). Flumes are static in nature - having no moving parts - and develop a relationship between the water level in the flume and the flow rate by restricting the flow of water in various ways.įlumes can accelerate slow, sub-critical (F r1) by:Īccelerating slow flow to a supercritical state creates upstream conditions where - under free-flow conditions - the flow rate can be determined by measuring the water level at a single, defined point in the flume (H a). ![]() Flumes are specially shaped, engineered structures used to measure the flow of water in open channels. ![]()
0 Comments
Leave a Reply. |
AuthorWrite something about yourself. No need to be fancy, just an overview. ArchivesCategories |