Mooring Model Coefficients for Barge Tows in a Navigation Lock

Abstract

The equations of motion of a spring-mass system are used to describe a vessel’s mooring system. These equations employ added mass and hydrodynamic damping coefficients, which depend on vessel shape and the proximity of free-surface and solid boundaries. The present study has experimentally determined these coefficients for barge tows moored in the chamber of navigation locks. Seven lock chamber configurations were tested in which the width, depth, and length of the chamber and the beam width and length of the tow were varied. Values of the added mass coefficient and a nondimensional form of the damping coefficient are presented. Subsequent to modeling flow in a lock chamber, these coefficients can be used in conjunction with hawser properties (spring constants) to estimate hawser forces generated during locking operations.