Hydrodynamic Resistance Reduction in Catamaran Assisted Hydrofoils

The present paper contains the test results of a planing catamaran model. The aim of the tests was to study the effect of hydrofoil in these types of crafts. First, experiments were carried out on the bare body (i.e. without hydrofoils) to obtain non-dimensional hydrodynamic resistance coefficient versus speed. Then, the model with hydrofoils, by various locations and attack angles were subjected to tests and the results were compared with those from the tests with the bare body. Results show that great reduction in hydrodynamic resistance of hydrofoil-supported catamaran is accessible especially at high speeds. In addition, hydrofoils positioning is important and un-suitable designs may result in instability in motion and increased in hydrodynamic resistance.