Effects of surface waves on underwater pipelines

The complex viscous flow around a submerged pipeline in the presence of surface waves has been investigated through numerical simulations and laboratory experiments for various wave characteristics and pipeline locations. The time-dependent Navier-Stokes equations were solved numerically in their finite difference formulation. The results have been compared very favorably with experimental data obtained in the present investigation and data available in the literature. The experimental part of the present investigation included the time-dependent measurement of the two components of the hydrodynamic forces acting on the pipeline model simultaneously in a laboratory wave tank under well-controlled wave parameters. The wave characteristics were determined by placing two differential pressure transducers of high sensitivity at various depths below the surface