Numerical Assessment of Air Lubrication System for Tanker

Published in: ICSOT 2023 conference

Authors: Himanshu Uppal, J Ram Kumar, KSS Srinivas, SS Dhavalikar

Date of Publication: December 8-9, 2023

The "Initial IMO Strategy on Reduction of GHG Emissions from Ships" sets forth the ambitious objective of eliminating Greenhouse Gas (GHG) emissions from ships by the close of this century.

Achieving this goal necessitates the implementation of a diverse array of measures, including optimized ship operations, adoption of alternative fuels, and the development of innovative technologies. Consequently, there has been a surge in interest regarding strategies to reduce ships' fuel consumption. One promising approach involves reducing hull friction using Air Lubrication System (ALS), which accounts for a significant fuel consumption, contingent on factors such as speed and draft. Extensive research has thus been undertaken to reduce frictional component of resistance by incorporating an air layer beneath the ship's hull

In the present study, a numerical investigation is conducted to assess the performance of an ALS on a full-scale ship (tanker). The ALS system is modelled by incorporating an air injection slit on the flat bottom. The objective is to evaluate the net power savings achieved by injecting air through the slits at the flat bottom of the vessel. The CFD simulations involve varying the air injection speed within the range of 0.2 to 0.6 m/s to investigate the effect of different air flow rates. Two configurations of air injection slits are considered to monitor the air layer and its impact on the reductions of air lubrication system. Conclusions are drawn towards the effect of Air- Injection rate, arrangement of air injection slits in terms of savings in power