scholarly journals QUANTITATIVE TRACING OF LITTORAL DRIFT

1968 ◽  
Vol 1 (11) ◽  
pp. 20
Author(s):  
Per Bruun
Keyword(s):  
Wave Action ◽  
Transport Layer ◽  
Hydraulic Lift ◽  
Bed Load ◽  
Wave Power ◽  
Fluorescent Tracers ◽  
Littoral Drift ◽  
Load Transport ◽  
Bed Load Transport ◽  
Horse Power

Tests were run at Fernandina Beach, Florida, using fluorescent tracers and bed load traps with automatic doors and hydraulic lift to determine the thickness of the bed load transport layer on the bottom ("bottom creep") (ref.l). Four special bed load traps with hydraulic remote controlled doors were installed on an ab. 800 ft. long pier. Fig. 1. Tracers of various colours were dumped at various distances from the pier. Two types of bottom profiles, Fig. 2, "berm profile" and Fig. 3, "bar-profile" were tested. As an example Fig. 4 shows test arrangement and wave action for test No. 17 (berm profile). Longshore wave power for this particular test was 1,5 Watts per ft of wave (one Watt is ab. 0,1 kg m/sec or ab. 0,0014- Horse Power), H, ,, was o,45 m, T, ,„ was 4-5 sec.

scholarly journals INFLUENCE OF GRAIN SIZE ON LITTORAL DRIFT

1970 ◽  
Vol 1 (12) ◽  
pp. 56 ◽  
Author(s):  
Jose Castanho
Keyword(s):  
Grain Size ◽  
Shear Stress ◽  
Bed Load ◽  
Flow Conditions ◽  
Littoral Drift ◽  
Flow Shear ◽  
Load Transport ◽  
Bed Load Transport ◽  
Flow Shear Stress ◽  
Load Discharge

Influence of grain size in sediment transport depends on flow conditions For bed load transport a maximum probably exists for load discharge as a function of gram size The important parameter seems to be the ratio To/T between the threshold shear stress and the flow shear stress.

scholarly journals LITTORAL DRIFT AS FUNCTION OF WAVES AND CURRENT

1968 ◽  
Vol 1 (11) ◽  
pp. 26 ◽  
Author(s):  
E.W. Bijker
Keyword(s):  
Wave Motion ◽  
Sandy Beaches ◽  
Bed Load ◽  
Longshore Current ◽  
Littoral Drift ◽  
Engineering Research ◽  
Actual Computation ◽  
Load Transport ◽  
Bed Load Transport ◽  
The Waves

For the computation of littoral drift due to waves hitting a coast obliquely, most formulae are based upon the assumption that this longshore transport is some function of the energy flux of the waves towards the coast. For the actual computation the component of this flux parallel to the coast is introduced. Most of the available prototype data are incorporated m the formula of the U.S. Army Coastal Engineering Research Center (ref. 4 and 1). In this formula no reference is made to the gram size and the slopes of beach and foreshore. The explanation for the fact that nevertheless reasonable results are obtained is probably owing to the fact that variation of gram size and beach slope for sandy beaches is not so very great. A more serious disadvantage is, however, that it is not possible to take into account the influence of a possible longshore current which is not generated by the wave motion, such as for instance tidal currents. In this paper an attempt is made to compute the littoral drift, starting from the longshore current velocity as it is generated by the waves or as it may originate from other causes (ref. 4). For the actual computation of the bed load transport a normal bed load transport formula is used, in which, however, according to the method developed by the author in earlier studies, the bed shear is increased as a result of the wave motion (ref. 2). From the tests briefly described in the present paper it becomes clear that the transport may be treated indeed as a function of the longshore current, even when this current has a direction opposite to that of the component of the wave propagation parallel to the coast.

scholarly journals Experimentally determined distribution of granular-flow characteristics in collisional bed load transport

2018 ◽  
Vol 180 ◽  
pp. 02061
Author(s):  
Václav Matoušek ◽  
Štěpán Zrostlík ◽  
Luigi Fraccarollo ◽  
Anna Prati ◽  
Michele Larcher
Keyword(s):  
Two Phase Flow ◽  
Imaging Techniques ◽  
Local Level ◽  
Flow Characteristics ◽  
Transport Layer ◽  
Bed Load ◽  
Phase Flow ◽  
Two Phase ◽  
Load Transport ◽  
Bed Load Transport

A series of laboratory experiments on turbulent open-channel two-phase flow in a form of intense bed load transport is reported. Measurements in a laboratory tilting flume included camera based imaging techniques to identify the structure of the flow at the local level. Obtained experimental distributions of two-phase flow related parameters - granular velocity, concentration, and temperature - across a collisional transport layer are discussed. The results are analysed together with additional measured quantities (discharges of mixture and grains, flow depth, bed slope etc). Our major goal is to evaluate the distribution of granular stresses across the transport layer with a special attention paid to the interface between the transport layer and the bed. Furthermore, comparisons are discussed between the experimental results and predictions produced by suitable kinetic-theory based models.

NUMERICAL MODEL TO SIMULATE THE EROSION ON THE SLOPE DUE TO OVERTOPPING

2010 ◽  
Vol 13 (3) ◽  
pp. 78-87
Author(s):  
Hoai Cong Huynh
Keyword(s):  
Numerical Model ◽  
Flow Model ◽  
Bed Load ◽  
Experiment Data ◽  
Step Method ◽  
Morphological Model ◽  
Load Transport ◽  
Bed Load Transport ◽  
The Finite Difference Method ◽  
Good Agreement

The numerical model is developed consisting of a 1D flow model and the morphological model to simulate the erosion due to the water overtopping. The step method is applied to solve the water surface on the slope and the finite difference method of the modified Lax Scheme is applied for bed change equation. The Meyer-Peter and Muller formulae is used to determine the bed load transport rate. The model is calibrated and verified based on the data in experiment. It is found that the computed results and experiment data are good agreement.

scholarly journals Experimental Study on Bypassing Tunnel of Bed Load Transport in a Reservoir

1996 ◽  
Vol 40 ◽  
pp. 813-818
Author(s):  
Minoru HARADA ◽  
Kazuo ASHIDA ◽  
Takashi DENO ◽  
Yuji OHMOTO
Keyword(s):  
Experimental Study ◽  
Bed Load ◽  
Load Transport ◽  
Bed Load Transport

Measuring Bed Load Transport Rates by Grain-Size Fraction Using the Swiss Plate Geophone Signal at the Erlenbach

2016 ◽  
Vol 142 (5) ◽  
pp. 04016003 ◽  
Author(s):  
Carlos R. Wyss ◽  
Dieter Rickenmann ◽  
Bruno Fritschi ◽  
Jens M. Turowski ◽  
Volker Weitbrecht ◽  
...  
Keyword(s):  
Grain Size ◽  
Size Fraction ◽  
Bed Load ◽  
Load Transport ◽  
Bed Load Transport
Sign in / Sign up

Export Citation Format

Share Document