Class 1 (Chief Engineer) Engineering Management 📅 Jan 2023

Exam Question

Improvements in Rudder efficiency can considerably contribute in improving propulsion effectiveness. Discuss common rudder-efficiency improvement devices / techniques currently in use, referring to the following:

(a) Rudder Thrust Fins

(b) Asymmetric Rudders

(d) Grim vane Wheeis.

Reference Answer

### Introduction to Rudder Efficiency
Improving rudder efficiency is a critical aspect of enhancing a vessel's overall propulsive effectiveness. The primary goal is to minimize the rudder's own hydrodynamic resistance while maximizing its ability to recover energy from the propeller slipstream, which would otherwise be lost. The propeller imparts a significant rotational component (swirl) to the water it displaces. Energy Saving Devices (ESDs) fitted to or integrated with the rudder are designed to convert this rotational kinetic energy into useful axial thrust, thereby reducing the required engine power for a given speed and leading to substantial fuel savings.
### (a) Rudder Thrust Fins
**Concept and Principle:**

Full answer on MeoMock — surveyor-grade reference answers for 7,000+ written exam questions.

View plans Browse library

← Browse more questions

Prepare on Android — MeoMock on Google Play