Large wave tanks 



From 1955, the BEB and later, its successor organization CERC, operated 

 a tank 193.5 m long, 4.6 m wide, and 6.1 m deep that was equipped with a 

 monochromatic wave generator. The terminology "tank" implies that cross- 

 shore processes dominate over longshore processes. This facility began a 

 new era of laboratory experimentation with length scales of the waves and 

 beach sufficient to reproduce beach change of engineering significance on field 

 beaches. The pioneering study of Saville (1956) using this facility demon- 

 strated that scale effects in small laboratory facilities could lead to morpho- 

 logic states different than those occurring at full scale. Although such effects 

 were known to engineers (Johnson 1949), they could not be quantified until 

 large facilities were available. The USACE large wave tank was mothballed 

 in 1983, and the historic beach profile change experiments involving breaking 

 waves up to 1.6 m in height and with periods up to 16 sec are documented in 

 Kraus and Larson (1988). This data set continues to be a source of quantita- 

 tive information for understanding beach profile change and for improving 

 predictive tools such as numerical models of beach profile change. 



A large wave tank (LWT) capable of producing waves and beach profile 

 change without introducing scaling problems provides an inexpensive means, 

 as compared with field data collection, of obtaining data for developing 

 numerical simulation models of beach profile change and for investigating 

 fundamental hydrodynamic and sediment-transport processes under controlled 

 conditions. A number of LWT experiments on beach change have been per- 

 formed (e.g., Kajima et al. 1982, Vellinga 1986, Dette and Uliczka 1987) 

 since the pioneering study of Saville (1956), but none has taken advantage of 

 the full range of modern instrumentation to capture the breadth of processes 

 acting across the profile. 



Genesis of SUPERTANK 



In 1987, in support of numerical model development for predicting storm- 

 induced beach erosion, staff at CERC concerned with numerical simulation of 

 beach change and the associated hydrodynamics began planning an LWT re- 

 search effort that was called the SUPERTANK Laboratory Data Collection 

 Project, or, simply "SUPERTANK." The project was conducted by contract- 

 ing for the LWT facility and supporting technical staff members located at the 

 O.H. Hinsdale Wave Research Laboratory (WRL), Oregon State University 

 (OSU). The WRL refers to this facility as a "channel" to connote that the 

 processes developed in it are primarily two-dimensional or cross-shore, and 

 that its major axis is aligned horizontally and not vertically. This usage will 

 be maintained in discussions referring specifically to the facility. The WRL 

 facility is the largest wave channel in the United States in which a sandy beach 

 can be emplaced. 



As planning progressed, it was realized that the offshore region could 

 provide an ideal environment for hydrodynamic (waves and currents) and 



Chapter 1 Introduction to SUPERTANK 



