Pressure Fluctuations in Submerged Jump

Mean velocities and pressures in the submerged jump downstream of a sluice gate have been investigated. The empirical relationship between the rate of expansion of the jet and the rate of decay of the maximum velocity, u_m, have been obtained. The results are compared with those of classical wall jet profiles. The magnitudes and variation pattern of pressure fluctuations along the channel bottom in a free hydraulic jump have been found to agree with those of earlier investigators. The main emphasis in this paper is on the measurement of pressure fluctuations in a submerged hydraulic jump and its relationship with the efflux Froude number and submergence. It has been shown that the pressure fluctuations along channel bottom in a submerged hydraulic jump are lower than that in a free jump — a significant characteristic which may be considered in designing a mobile bed channel, since it governs the inception and rate of erosion of the channel bed.