Resistance reduction on trimaran ship model by biopolymer of EEL slime

Resistance reduction in ship becomes an important issue to be investigated. Energy consumption and its efficiency are related toward drag reduction. Drag reduction in fluid flow can be obtained by providing polymer additives, coating, surfactants, fiber and special roughness on the surface hull. Fish skin surface coated with biopolymers viscous fluid (slime) is one method in frictional resistance reduction. The aim of this research is to understand the effect of drag reduction using eel slime biopolymer in unsymmetrical trimaran ship model. The investigation was conducted by towing tank test with variation of speed. The dimension of trimaran model are L = 2 m, B = 0.20 m and T = 0.065 m. The ship model resistance was precisely measured by a load cell transducer. The comparison of resistance on trimaran ship model coated and uncoated by eel slime are shown on the graph as a function of the total drag coefficient and Froude number. It is revealed that the trimaran ship model with eel slime has higher drag reduction compared to trimaran without eel slime at similar displacement. The result shows that the drag reduction is about 11 % at Fr 0.35.