гурвалжин ус халиагуур
треугольный измерительный водослив с тонкой стенкой
Нимгэн ханатай, ус хэмжих зориулалтын урвуу гурвалжин хэлбэрийн ус халиагуур.
Эх сурвалж:In this case, the notch is “V” in shape. Depth of water above the bottom of the V is called head (H). The V-notch design causes small changes in discharge hence causing a large change in depth and thus allowing more accurate measurement than with a rectangular weir. Head (H) should be measured at a distance of at least 4H upstream of the weir.
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