efflux time measurements are carried out for gravity draining of a liquid from a large cylindrical tank (where the flow is essentially laminar) through single exit pipe in the absence and presence of cetyl pyridinium chloride (cpc) surfactant solutions. the variables considered are initial height of liquid in the tank, dia. of tank, length of the exit pipe and concentration of surfactant. the d...

Quantifying the preferred transition speed (PTS) from walking to running has provided insight into the underlying mechanics of locomotion. The dynamic similarity hypothesis suggests that the PTS should occur at the same Froude number across gravitational environments. In normal Earth gravity, the PTS occurs at a Froude number of 0.5 in adult humans, but previous reports found the PTS occurred a...

Efflux time measurements are carried out for gravity draining of a liquid from a large cylindrical tank (where the flow is essentially laminar) through single exit pipe in the absence and presence of Cetyl Pyridinium Chloride (CPC) surfactant solutions. The variables considered are initial height of liquid in the tank, dia. of tank, length of the exit pipe and concentration of surfactant. T...

Animals of different sizes tend to move in a dynamically similar manner when travelling at speeds corresponding to equal values of a dimensionless parameter (DP) called the Froude number. Consequently, the Froude number has been widely used for defining equivalent speeds and predicting speeds of locomotion by extinct species and on other planets. However, experiments using simulated reduced gra...

A control-volume analysis of a hydraulic jump is used to obtain the mean vorticity downstream of the jump as a function of the Froude number. To do this it is necessary to include the conservation of angular momentum. The mean vorticity increases from zero as the cube of Froude number minus one, and, in dimensionless form, approaches a constant at large Froude number. Digital particle imaging v...

A hydraulic jump is a sudden, rapid transition from a supercritical flow to a subcritical flow. At large inflow Froude numbers, the jump is characterized by a significant amount of entrained air. For this paper, the bubbly two-phase flow properties of steady and strong hydraulic jumps were investigated experimentally. The results demonstrate that the strong air entrainment rate and the depth-av...

The Froude number has been widely used in anthropology to adjust for size differences when comparing gait parameters or other nonmorphological locomotor variables (such as optimal walking speed or speed at gait transitions) among humans, nonhuman primates, and fossil hominins. However, the dynamic similarity hypothesis, which is the theoretical basis for Froude number corrections, was originall...

The authors explore the theoretical and empirical relationship between the nonlocal quantities of the entrainment ratio E, the appropriately depthand time-averaged flux coefficient G, and the bulk Froude number Fro in density currents. The main theoretical result is that E 5 0.125 G Fr 2 o(C 3 U /CL)/cosu, where u is the angle of the slope over which the density current flows, CL is the ratio t...

In 1946, Vedernikov developed a stability criterion for uniform flow in open channels. A global parameter proposed by Vedernikov has been widely accepted as a measure of flow stability. Recognizing the significance of the role of the parameter playing in the stability of open-channel flows, hydraulicians have thenceforth called it the Vedernikov number. Alternatively, the Vedernikov number may ...