Abstract:
Side weirs and side sluice gates are diversion structures widely
used in irrigation engineering. A side weir is an overflow weir framed
in the side of a channel over which lateral outflow takes place when the
water surface in the channel rises above the weir crest. A side sluice
gate is an opening in the side of a channel through which lateral
outflow takes place.
For computation of sharp crested side weir discharge De Marchi
equation is widely used with a constant value of discharge coefficient.
Various investigators have proposed different equations relating the
weir discharge coefficient to the main channel upstream Froude number F
only. The predicted side weir discharge based on these equations will be
markedly different for the same values of F This is evidently so due
to the fact that other variables like weir height, channel slope,
channel roughness, channel bed width etc., which affect the weir
discharge have not been considered by these investigators. Further,
inspite of their great practical importance, little attention has been
given to the study of flow over broad crested side weirs and through
side sluice gates.
(i)
In the present study, the concept of a discharge coefficient for an
elementary strip along the length of side weir or side sluice gate is
introduced. Equations of the elementary discharge coefficient for
various shapes of side weir and rectangular side sluice gate have been
obtained. A common methodology involving the solution of the proposed
Elementary discharge coefficient equation and the spatially varied flow
equation has been evolved for the prediction of discharge and flow
profile along the diversion structure.
(
