Journal of Engineering Mathematics

, Volume 76, Issue 1, pp 33–57

# The effect of slatted screens on waves

• S. Crowley
• R. Porter
Article

## Abstract

A linearised model is proposed for the transmission of waves through thin vertical porous barriers, where both the inertial and dominant quadratic drag effects are included. A boundary-value problem is developed in which linear boundary conditions holding along the length of the screen are derived from a pair of canonical wave problems, one including an exact geometric description of a slatted screen to determine an inertia coefficient and the other using a quadratic drag law to determine an equivalent linear drag coefficient. The model is then applied to a range of wave scattering and sloshing problems involving thin vertical slatted screens in various settings. In each case results are verified by comparison to the solution of a direct non-linear calculation where the effects of drag have been isolated. We show that the solution to our canonical problem provides a good approximation to the solution of each of the model problems.

## Keywords

Inertial effects Quadratic drag law Slatted screens Water waves

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