Notches and Weirs- Their classification and types
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Notch- is a device used for measuring the rate of flow or discharge of a liquid through small channel or tank. Weir- is a concrete or masonry structure, placed in an open channel over which the flow occurs. It is form of vertical wall , with the sharp edge at the top, running all the way across the open channel. Notches Weirs 1. A notch may be defined as an opening provided in one side of a tank or reservoir,with upstream liquid level below the top edge of opening. 1. A weir may be defined as a structure constructed across a river or canal to store water on the upstream side. 2. The sheet of water flowing through a notch is called Nappe. 2. The sheet of water flowing over a weir is called Vein. 3. The bottom edge of a notch is called Crest. 3. The bottom edge of a weir is called Sill. 4. Usually made of metallic plates. 4. Weir is a concrete or masonry structure 5. Measures small discharge of small stream, lake or canal. 5. It...