In this paper the influence of a vertical lip upon the contraction coefficients of underflow gates is discussed.
The coefficients of inclined gates with a vertical lip are investigated theoretically by using the method of conformal mapping. Solutions are obtained numerically for several values of the inclination of gate bottom. Theoretical solutions show that;as the length of a lip
increases, the coefficient rapidly decreases from the value
for the inclined gate, and when the length becomes of the
order of a gate openning,it takes a value to be nearly equal to that for a vertical gate. These theoretical results are verified by experiments.