Accession Number : ADA185083

Title :   Nearshore Sand Transport.

Descriptive Note : Final rept.,

Corporate Author : CALIFORNIA UNIV SAN DIEGO LA JOLLA

Personal Author(s) : White, Thomas E

PDF Url : ADA185083

Report Date : Jan 1987

Pagination or Media Count : 229

Abstract : Sand transport as bedload on nearly flat beds in shallow water outside the breakers is the subject of this study. The appropriate variables necessary for computation of sediment transport are grouped into a few dimensionless force ratios using the techniques of dimensional analysis, forming a sediment transport model. Field experiments measuring fluid velocity and sand transport were performed seaward of the breaker region. Fluorescent sand tracer was used to measure both sediment-transport velocity and thickness. Thirty tracer experiments were performed under differing wave and sediment conditions. Transport thickness is well correlated with orbital diameter but not wave height or fluid velocity. Different powers of the fluid velocity are compared with sediment transport. The lower velocity moments perform much better than the higher moments. Use of a threshold criterion is essential in predicting whether the sand transport is onshore or offshore. Results suggest that the appropriate power of fluid velocity necessary for computing and transport may itself be a function of the flow intensity.

Descriptors :   *SEDIMENT TRANSPORT, *SAND, SHALLOW WATER, FLUID FLOW, VELOCITY, THICKNESS, MATHEMATICAL MODELS, LITTORAL DRIFT, FIELD TESTS, FLUORESCENT DYES, TRACER STUDIES, SAMPLING, THESES

Subject Categories : Physical and Dynamic Oceanography
      Fluid Mechanics

Distribution Statement : APPROVED FOR PUBLIC RELEASE