The Effect of Mewis Duct Energy Saving Device to Propeller Performance

Abstract

Installation of ESD (Energy Saving Device) can improve ship propulsion performance. Mewis Duct is one type of ESD (Energy Saving Device) multi-component device that combines nozzle and fin into the nozzle. The structure can minimize losses due to small losses at the ship's stern and rotational losses or loss of thrust in the slipstreams area. Mewis Duct can reduce power by about 3-8% and increase thrust on the propeller by about 2-5%. This study aims to improve the performance of the INSEAN e779a propeller type using Mewis Duct. The modified Mewis ducts are the number of fins four, five, six asymmetrical and four symmetrical fins using the computational fluid dynamics (CFD) approach. The CFD code is based on the RANS (Reynolds - Averaged Navier Stokes) equation with the turbulent model is k-ϵ. This study found that installing Mewis duct as ESD in a ship increased the propeller thrust by 3-5% and the torque by 3-4%.