American Society of Civil Engineers

A Simple Method for Evaluating Undertow Velocity Distributions over Arbitrary Beach Forms

by Daisuke Aoike, (Graduate student, Dept. of Civil Eng., Univ. of Tokyo, Hongo-7, Bunkyo-ku, Tokyo, 113-8656.), Akira Watanabe, (Professor, Dept. of Civil Eng., Univ. of Tokyo, Hongo-7, Bunkyo-ku, Tokyo,113-8656. E-mail:, and Masahiko Isobe, (Professor, Inst. of Environmental Studies, Univ. of Tokyo, Hongo-7, Bunkyo-ku, Tokyo,113-8656.)
Section: Part I Characteristics of Coastal Waves and Currents, pp. 1282-1292, (doi:

     Access full text
     Purchase Subscription
     Permissions for Reuse  

Document type: Conference Proceeding Paper
Part of: Coastal Engineering 2000
Abstract: A new method is proposed for evaluating the cross-sectional distributions of the undertow (return flow) velocity in a surf zone over arbitrary bottom-forms in a fairly simple manner. It is based on an energy budget concept, a surface roller model and a Boussinesq-type wave equation set including a breaker-induced momentum diffusion term. Validity and applicability of this method for various wave and beach conditions are examined by comparing computed undertow velocity distributions with laboratory measurements.

ASCE Subject Headings:
Surf zones
Velocity distribution
Wave equations