Hydrodynamic Forces Acting on a Cylinder Towed in Muddy Environments

Abstract

The presence of natural mud in the seabed of waterways and ports has an impact on maritime traffic in many parts of the world. Previous research has shown that sailing safely through fluid mud is possible. However, the majority of these studies were experimental and model scale research, omitting many important characteristics of the natural mud to simplify the problem. The research was therefore directed toward computational fluid dynamics (CFD) models to describe the complex properties of the natural mud for nautical applications. Nonetheless, the lack of validation material makes the usage of CFD still uncertain. This work aims to contribute validation cases for numerical solvers through a series of towing tests in muddy environments with a 0.2-m-diameter cylinder. Different fluid combinations are tested, including freshwater, natural mud only, and natural mud with seawater on top. Experimental results in a single interface of natural mud are compared with CFD simulations using three different viscosity laws. Forces calculated using CFD were found to underpredict experimental measurements, indicating that more attention is needed toward describing the natural mud.