Chapter V 



OCEAN ENGINEERING FOR SUBSEA OPERA 

 TIONS 



The severity of the ocean environment dictates the need for a broad 

 understanding of the various oceanic properties and processes that im- 

 pact, to some degree, on the development of technology to facilitate 

 manned and unmanned subsea operations. Consequently, such develop- 

 ments rely heavily on Government-supported fundamental research. 

 Certain areas of fundamental research, however, are especially perti- 

 nent to undersea operations. For example, the National Science Founda- 

 tion (NSF) is supporting research on the follou'ing: The effects of tem- 

 perature on the geotechnical properties of deep-ocean sediments; the 

 properties of deep-ocean sediments; the properties of buoyancy-induced 

 flows; heat removal and thermal plumes issuing from objects in ther- 

 mally stratified fluids; the turbulent nature of water below the airwater 

 interface; the long-range problems in developing improved acoustic- 

 imaging systems for use in the ocean. 



The United States Navy (USN) has been involved in a number of 

 geophysical investigations of the ocean bottom, studies of anomalies 

 associated with the gravity field, investigations of sedimentation and 

 bottom processes, and ocean bottom roughness as related to acoustic 

 reverberation or reflection. The Office of Naval Research also supported 

 a study to understand the phenomenon of cable strumming in the hy- 

 drospace environment and provided expertise and advice on acoustic 

 and nonacoustic detection systems for clearance operations in the Suez 

 Canal. 



The U.S. Geological Survey (USGS) is coordinating a broad 

 multidisciplinary research and engineering study of sediment instability 

 and movement. The study involves several governmental agencies, 

 universities, oil companies, and an electronics firm. It was initiated after 

 earlier investigations had provided tangible evidence that major storms 

 could trigger massive failures in sediments supporting offshore plat- 

 forms and pipelines. During the initial study phase, USGS and university 



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