41. NODA, E.K., et al., "Nearshore Circulations under Sea Breeze 

 Conditions and Wave-Current Interactions in the Surf Zone," Report 

 TETRAT-P-72-149-4, Tetra Tech., Inc., Pasadena, Calif., Feb. 1974. 



Keywords . Current Depth Refraction; Currents, Nearshore; Currents, 

 Wave-Induced; Numerical Model; Surf Zone. 



Discussion. A numerical model of waves approaching a beach is extended 

 to include wave-current interaction. The beach topography, which is 

 relatively complicated, and the wave conditions are chosen to represent 

 a field example which had been previously studied. 



The approximations used include linearized equations of motion and 

 a "ray theory" approach to the wave-current and wave-bed interaction. 

 However, the calculations used a finite-difference approximation since 

 this proved more efficient than computing rays. A steady state was 

 assumed and calculated. 



The results show appreciable differences from earlier computations 

 with no wave-current interaction. However, there is room for 

 improvement. Indeed, it is stated that "the nearshore circulation 

 system is basically a nonsteady pulsating system." 



Coastal Engineering Significance. This is an early attempt to study 

 wave-current interaction under realistic surf zone conditions. The 

 system that is modeled is too complicated for interpreting the various 

 physical effects that are included. An improved development of this 

 model is used in a simpler context by Ebersole and Dalrymple (1980). 



42. PEREGRINE, D.H., "Interaction of Water Waves and Currents," 

 Advances in Applied Mechanics^ Vol. 16, Academic Press, New York, 

 1976, pp. 9-117. 



Keywords. Averaged Lagrangian; Caustics, Current Refraction; Current 

 Velocity Profile; Currents, Large-Scale; Currents, Opposing; Currents, 

 Shearing; Currents, Slowly Varying; Currents, Small-Scale; Currents, 

 Unidirectional; Dispersion Relation; Equations of Motion; Group 

 Velocity; Interactions, Short Wave-Long Wave; Review; Theory; Theory, 

 Ray; Turbulence, Wave Action; Wave Energy; Waves, Finite-Amplitude. 



Discussion. This substantial review paper commences with a description 

 of the various situations in which waves interact with preexisting 

 currents. Wave-generated currents are not discussed in this work. 



More than half the paper is devoted to currents which vary on a 

 scale much larger than the waves. The dispersion equation for waves on 

 a constant current yields a wider range of solutions for a given 



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