open channel

Open channel

A covered or uncovered conduit in which liquid (usually water) flows with its top surface bounded by the atmosphere. Typical open channels are rivers, streams, canals, flumes, reclamation or drainage ditches, sewers, and water-supply or hydropower aqueducts.

Open-channel flow is classified according to steadiness, a condition in relation to time, and to uniformity, a condition in relation to distance. Flow is steady when the velocity at any point of observation does not change with time; if it changes from instant to instant, flow is unsteady. At every instant, if the velocity is the same at all points along the channel, flow is uniform; if it is not the same, flow is nonuniform. Nonuniform flow which is steady is called varied; nonuniform flow which is unsteady is called variable.

Flow occurs from a higher to a lower elevation by action of gravity. If the phenomenon is short, wall friction is small or negligible, and gravity shapes the flow behavior. Gravity phenomena are local; they include the hydraulic jump, flow over weirs, spillways, or sills, flow under sluices, and flow into culvert entrances.

If the phenomenon is long, friction shapes the flow behavior. Friction phenomena include flows in rivers, streams, canals, flumes, and sewers.

open channel

[′ō·pən ′chan·əl]
(science and technology)
Any natural or artificial, covered or uncovered conduit in which liquid (usually water) flows with its top surface bounded by the atmosphere.
References in classic literature ?
The yellow cog had now shot out from the narrow waters of the Solent, and was plunging and rolling on the long heave of the open channel.
This open channel to the highest life is the first and last reality, so subtle, so quiet, yet so tenacious, that although I have never expressed the truth, and although I have never heard the expression of it from any other, I know that the whole truth is here for me.
Dorothea's nature was of that kind: her own passionate faults lay along the easily counted open channels of her ardent character; and while she was full of pity for the visible mistakes of others, she had not yet any material within her experience for subtle constructions and suspicions of hidden wrong.
Tenders are invited for Procurement of open channel flow apparatus for hydraulics laboratory
Constantinescu, Koken, and Zeng (2011) considered the flow in an open channel bend of strong curvature (the ratio between the radius of curvature of the curved reach and the channel width is close to 1.
Moglen presents a textbook for a first course in open channel flow within an undergraduate civil engineering program, focusing on the most fundamental concepts and leaving more advanced matters to other texts and courses.
The assay runs on an open channel of a laboratory analyzer.
The product family now also includes Open Channel Policy Enforcement, Open Channel Seamless Mobility and Open Channel Wi-Fi QoE.
FusionLine features a 4-6mm open channel on the product side, which is easy to CIP and fully accessible.
In addition to our web-site, emails, news releases and quarterly reports, the app is another means to maintain an open channel of communication with the investment community.
Open channel flow; numerical methods and computer applications.
Water flowing in an open channel runs in relatively complex manner due to various influencing factors, including slope steepness, surface roughness, and the so-called hydraulic radius.