General information

SlenderFlow software uses slender-body theory to calculate the flow of water around ships. It is developed by Dr Tim Gourlay at Perth Hydro, and used for our ship hydrodynamics consulting. As a potential-flow code, it is very numerically efficient, with computation times typically a fraction of a second.

Inputs

• Hull shape (exact offsets, or use a modified standard hull)
• Ship speed
• Channel type
• Channel dimensions

Outputs

• Squat and dynamic draft at bow, midships and stern
• Hydrodynamic pressure around ship and on seabed
• Drawdown on canal banks

Ship types

SlenderFlow may be used for any displacement (non-planing) vessel, including ocean-going commercial and military vessels, European inland vessels, catamaran ferries and trimaran ferries.

Bathymetry types

• Shallow open water
• Dredged channels
• Canals (Panama, Suez)
• European inland waterways

Recent validation articles

Container ship dynamic sinkage prediction, using the nonlinear Rankine-source panel code, phFlow

Under-keel clearance: what lies beneath?

Benchmarking of DIFFRAC, FATIMA, HydroSTAR, MOSES, NEMOH, OCTOPUS, PDStrip, RAPID, SEAWAY, SlenderFlow and WAMIT against measured vertical motions of the Duisburg Test Case container ship in shallow water

Validation of container ship squat modelling using full-scale trials at the Port of Fremantle

Application of potential flow methods to fast displacement ships at transcritical speeds in shallow water

Numerical investigation of the behaviour and performance of ships advancing through restricted shallow waters

Measurement and simulation of ship under-keel clearance in port approach channels

Bow and stern sinkage coefficients for cargo ships in shallow open water

Application of potential flow methods to ship squat in different canal widths

Sinkage and trim of modern container ships in shallow water

Image credits

Freight Ro-Ro in Thames Estuary, depth 16 m, speed 20 knots, courtesy of John Clandillon-Baker.