PREFACE 



This report is published to document the design, construction, and 

 operation of an oscillatory water tunnel. The test section of this 

 facility replicates prototype conditions at the seabed under sinusoidal 

 waves offshore of the breaker zone. The water tunnel, constructed in 

 the Fluid Mechanics Building of the National Bureau of Standards (NBS) , 

 Gaithersburg, Maryland, has performed satisfactorily for over 2 years in 

 studies of sand movement and transport. The work was carried out under 

 the coastal processes program of the U.S. Army Coastal Engineering 

 Research Center (CERC) . 



The report was prepared by Karl E.B. Lofquist, Physicist, Fluid 

 Mechanics Section, Mechanics Division, NBS, under CERC Agreement No. 

 76-30. Previous CERC Agreements Nos. 70-99 and 73-25 supported construc- 

 tion of the water tunnel. The author especially thanks Louis Lembeck 

 who shared the work of constructing the tunnel. 



Drs. M.M. Das and R.J. Hallermeier, Coastal Processes Branch, were 

 the CERC monitors for the agreements, under the general supervision of 

 Dr. C.J. Galvin, Jr., Chief, Coastal Processes Branch, Research Division. 



Comments on this publication are invited. 



Approved for publication in accordance with Public Law 166, 79th 

 Congress, approved 31 July 1945, as supplemented by Public Law 172, 88th 

 Congress, approved 7 November 1963. 



/T- LiF'v «■<■*»» 



JOHN H. COUSINS 



Colonel, Corps of Engineers 



Commander and Director 



