maldistribution, and the flow distribution shows three maxima along the channels. For the U-arrangement, a higher inlet flow rate of the cold plate shows more pronounced. Flow visualization for a total of five inlet configurations (namely, U-, I-, J-, L-, and Z-arrangements) are reported in this study. This study experimentally examines the influence of the inlet locations on the flow distributions of the multi-channel cold plate by means of particle image velocimetry (PIV). Finally the examination of new evidence for channel incision on the Beatton River shows that the river is downcutting at a rate of about 2 mm/yr, not at 10 mm/yr as reported earlier. These variations in migration rate are likely a response to fluctuating channel widths over time because of a short-term imbalance between the rate of cutbank erosion and the rate of point-bar sediment accumulation. This means that predictions of migration rates for individual bends, based on short-term measurements using erosion pins or aerial photographs, are highly suspect.
discontinuous process within any single bend. Recent data from forest successions on the floodplains of a variety of migrating rivers show that channel migration is a. New field data relating to bend migration rates with bend radius of curvature to channel width ratios (rm/w) for the Beatton River confirm the form of the relationship the writers described in 1975, although there is more variance than our initial results suggested. In the case of the strongest diurnal constituent (K1), the maximum inflowing current leads the maximum sea-level for about 4 hours in both inlets in the same way, at the most energetic semi-diurnal frecuency (M2) the maximum inflowing current leads the maximum sea-level for about 2 hours. These results were compared with sea surface elevation data at the same locations and for the same period of current measurement. The phase differences between both inlets shows that the inflowing current at Malamocco leads for about 20 minutes the one at Lido. the flow is almost entirely driven by the tidal signal. The whole set of constituents explains between 94 and 97% of the total variance, i.e.
Harmonic analysis is applied for determining the main tidal constituents in the flow. The preliminary results have shown a highly- dominant tidal signal with the polarization of the oscillations mainly along the channel axes. From these measurements is apparent that the currents can reach to almost 2 m/s with the corresponding flow rate about 10000 m3/s (for a comparison Po, the biggest Adriatic river has an average discharge rate of 1500 m3/s reaching only exceptionally a value of 11.000 m3/s). The vertical resolution is set to 1 meter and the three-components current is sampled and recorded every 10 minutes. The measurements initiated 17 June, 2001 at selected locations, namely Lido and Malamocco. Current measurements have been carried out with the bottom-mounted Acoustic Doppler Current Profiler (ADCP) so that in each inlet one ADCP has been installed. The first long-term monitoring of current flow in the inlets of the Venice lagoon has started in summer 2001.
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