3 SUPERTANK 

 Hydrodynamics 1 



Introduction 



Background 



At the SUPERTANK Laboratory Data Collection Project, waves and cur- 

 rents were measured along the wave channel with 16 resistance wave gauges 

 and 18 electromagnetic current meters. Wave gauges were deployed at 12-ft 

 (3.66-m) intervals from the mid surf zone to the wave paddle. The wave 

 gauges measured the water surface elevation as a function of time to give 

 wave height, wave period, and mean water level throughout the channel. 

 Current meters were deployed in vertical arrays inside and just outside the 

 surf zone. The current meters measured the cross-shore and vertical water 

 velocities as a function of time to give mean wave-induced current velocities. 

 Hydrodynamic data were processed with both spectral and time series 

 analyses. 



Objectives of hydrodynamic measurements 



The first objective of the hydrodynamic measurements at SUPERTANK 

 was to support the beach profile change studies, as waves and currents are the 

 driving forces for beach evolution. Within this objective, the measurements 

 also supported studies of sediment suspension and transport. The second 

 objective of the hydrodynamic measurements was to collect data for the devel- 

 opment and verification of advanced hydrodynamic models that describe such 

 processes as vertical current structure, wave breaking, transformation of bi- 

 modal spectra, wave setup, and nonlinear wave transformation. 



'Written by Jane McKee Smith, Coastal Engineering Research Center, U.S. Army Engineer 

 Waterways Experiment Station. 



55 



Chapter 3 SUPERTANK Hydrodynamics 



