Flume experiments

Baonold, R. A. Proc. Inst. Civ. Eng. (iii) 4 (1955) 174. Some flume experiments on large grains but little denser than the transporting fluid, and their implications. 

You are engaged in laboratory flume experiments on transfer of dissolved oxygen into the sediments below the flowing water. The goal is to measure the sediment-water mass transfer coefficient and relate it to other parameters of the flow fleld. The flume is 20 m in length, with a depth between 3 and 10 cm and velocity between... 

Flume experiments on settlement of oyster veligers were conducted with GGR at 10 7 M concentrations released by peristaltic pumps into small target wells lined with crushed oyster shells.7 The crushed shells acted as a diffuser, allowing the test solution to slowly seep upward. Settlement of the oyster larvae (Crassostrea virginica) on peptide-containing wells and adjacent control wells... 

Figure 3.38 Depth-averaged velocity distribution (signs) measured by Nuding in flume experiment No 11004, [470] there is a local minimum near the interface between vegetated (left) and free streams.

I.B. Kuffner (2001). Effects of ultraviolet radiation and water motion on the reef coral Porites compressa Dana A flume experiment. Mar. Biol, 138,467-476. 

Values of K8 for various isotopes are presented in Figure 3. Values of Kp derived from the flume experiments agree with the published concentration coefficients of radionuclides by edible plants (10). 

By determining DXy Ku and K2y it was possible to program a solution for Equation 1 and verify it through repeated flume experiments. 

The surface concentration distribution coefficients for sediments K8 and for plants Kp in contact with radioactive contaminated water were formulated and predicted for various radionuclides through aquaria studies and flume experiments. These values reflect the affinity of sediments and plants for various radionuclides. 

The third case, a pressure gradient induced by the bottom current and a supposed advective movement of the pore water, is of importance mainly on the shelf where shallow waters, fast currents, an uneven underground, and high permeability values in coarse sediments are encountered. Ziebis et al. (1996) as well as Forster et al. (1996) were able to demonstrate by in situ measurements and in flume experiments that the influence of bottom currents may be indeed crucial for the superficial pore water of coarse sand sediments near to the coast. 

At flow rates of about 10 cm s over an uneven sediment surface (mounds up to 1 cm high), the oxygen measured by means of microelectrodes had penetrated to a maximum depth of 40 mm, whereas a penetration depth of only 4 mm was measured under comparable conditions when the sediment surface was even (Fig 3.27). Huettel et al. (1996) were able to show in similar flume experiments that not only solutes, but, in the uppermost centimeters, even fine particulate matter was likewise transported into the pore water of coarsely grained sediments. Similar processes with marked advective fluxes are, however, not to be expected in the finely grained sediments predominant in the deep sea. 

The ways in which crustaceans deploy their antennules in ambient currents can affect water flow through the aesthetasc arrays. In our flume experiments with lobsters (Koehl et al. 2001), an ambient water current of 10 cm/s did not force water and odor filaments into the aesthetasc arrays on antennules held parallel to the flow direction, whereas water and odor samples did move into the arrays during flick down strokes of 6 cm/s (during a down stroke where the water flow relative to the antennule is perpendicular to the long axis of the antennule). This suggests that if... 

Simulation of depth-averaged flow and comparison with flume experiment... 

In figure 8, longitudinal profile of bed load deposition with time is depicted with the measured profile in the vegetated area after 12 min. and 20 min. As for the deposition of bed load in the upstream of the vegetated zone, we did not carried the measurement in the flume experiments. 

Figure 1. Lateral distribution of depth-averaged velocity (A) Sensitivity due to or value (B) Comparison with flume experiment (Tsujimoto 1996).

The flume experiment made it clear that CPOM was captured behind the crest of ripple by separation vortex, and was deposited. The CPOM particles transported to the rearward of crest of ripple is presented by the accumulation of supplied number density particle velocity Ug and capture ratio iff. The supplied number density and particle velocity are written as follows (Ashida Michiue 1972). 

As for the numerical calculation of CPOM, the temporal change of A on the basis of assumption of v =O.9,y0 = O.5. Our model showed that ripples were formed every 500 s, and propagated to the downstream. After 1500 s, there are 3 numbers of ripples formed. In addition, CPOM deposition A after 1200 s through the flume experiment was compared with calculation result A considering the following value = 0.02 cm/s, u = 5 cm/s (estimation by Equation (1)), Vg = 0.06/cm calculated by using supplied POM ratio and The calculated result is explained the experimental result in detail as shown in Figure 8. 

M. Onorato, A. R. Osborne, M. Serio, L. Cavaleri, C. Brandini and C. T. Stansberg, Extreme waves, modulational instability and second order theory Wave flume experiments on irregular waves, Eur. J. Mech. B/Fluids 25(5), 586-601 (2006). 

The quantity Mao varies with the solids volume fraction p = I —Up, where the porosity rip = ps — Pm)/ p.s Pw) and ps is the particle density, nominally equal to 2,650kgm for typical inorganic sediments. When < space-filling value of p below which the particles do not form a continuous matrix (i.e., mud is a fluid, and therefore cannot transmit a shear wave) and therefore Mao are nil. In the range of > psp, Vm rapidly increases with p. When waves begin to liquefy mud, Vm decreases even when p >psp) remains constant. In a flume experiment on a clayey mud bed at = 0.10, the onset of steady wave action caused Vm to decrease from 2 to 1.4ms in one hour. ... 

Fig. 39.1. Scott Russell flume experiment for generating solitary waves.

Cooper, R. H. 1970. A study of bed Material Transport Based on the Analysis of Flume Experiments. 

Guy, H. P., D. B. Simons, and E. V. Richardson. 1966. Summary of Alluvial Channel Data From Flume Experiments, 1956-1961. Paper No. 462-1. U.S. Geological Survey. 

Some of the most recent advances in larval settlement methodology involve using flumes to determine the response of larvae to chemical signals under various flow conditions (Butman et al. 1988 Butman Grassle 1992 Pawlik et al. 1991 Turner et al. 1994). In general, flume experiments have been performed by placing larvae and larval mimics (often glass spheres) into a flume upstream from an... 

Assuming that the observed kf values are a measure of the BBL transport coefficient p in Eq. 7, then they should be a ftinction of stream velocity. Correlations exist based on laboratory flume experiments that clearly show p increasing with flow. This may explain the spring-time kf increase as due to the increase stream flow which normally occurs after snow melt. For... 

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