8 Acoustic Doppler Current 

 Profiler Measurements at 

 SUPERTAIMK 1 



Introduction 



Background 



The participation of RD Flow in the SUPERTANK Laboratory Data 

 Collection Project was part of a long-term program to study the relationship 

 between acoustic backscatter and suspended sediment concentration. The 

 focus of this program, the PLUmes MEasurement System (PLUMES) (Kraus, 

 Thevenot, and Lohrmann 1992), concerns the objective of detecting and moni- 

 toring the long-term fate of dredged material after ocean discharge. The 

 SUPERTANK project provided an excellent testing ground to determine the 

 appropriate implementation of acoustics to serve this purpose. 



The use of acoustics is motivated by its profiling capability and its remote 

 sensing character. The profiling capability is important because suspension 

 phenomena exhibit strong vertical gradients that are difficult to resolve with 

 single-point measurement devices. Also, the vertical location of interest may 

 change, either because the bottom elevation changes (as in SUPERTANK) or 

 because the plume of suspended material is moving. The remote sensing char- 

 acter is important to avoid disturbances in the flow field. This is especially 

 true in the highly dynamic regime simulated in the SUPERTANK project. 



Objectives 



The objectives of the Acoustic Doppler Current Profiler (ADCP) measure- 

 ments at SUPERTANK were: 



'Written by Atle Lohrmann and Craig A. Huhta, SonTek, Inc. 

 Chapter 8 ADCP Measurements at SUPERTANK 



137 



