HYDRAULIC JUMP UNDER THE INFLUENCE OF CROSS JETS

Abstract

The influence of a plane cross jot on the characteristics of a hydraulic jump has been studied analytically and experimentally• Jets of two different angles of inclination with the vertical were used. Results of experiments on forced jump over a wide range of partinent variables are reported. Relations for conjugate depths and energy loss have been derived using momentum equation based on the some assumptions. The study has led to the following conclusions• (1) The theeorotLcal and observed values of conjugate depths ratio are in good agreement. (2) The assumption that the pressure at the jet section corresponds to (h1 - h2)/2 leads to bettor agree-ments as compared to assumption of zero pressure at the jet section. (3) The ratio of the length of the forced jump to post jump depth is a function of q3/q1 and F1• (4) The profile of the forced jump can be expr.?sped in a manner similar to that of free jump by select-ing proper length scale which is a function of F1 and q,/ql• (5) The local drag coefficent on the floor.- of a forced jump is smaller than that in a free jump at comparable f lo.w conditions.