The air bubbling system for use in reducing ice resistance of icebreaking ships was introduced in late 1960ies. After extensive development and testing the system has been used in several vessels till early 1990ies. The idea of the system is to blow compressed air down in the bilge area of the vessel hull and the expanding air bubbles will rise to the free water surface reducing the friction between ice and the hull surface.
The system has been in use mainly in icebreakers, but also on tankers, dry cargo vessels as well as ferries. The size of the vessels with air bubbling system varies between a small coastal ferry to cargo ships of over 20000 tonnes.
The benefits of the system are not only to reduce ice resistance, but also for instance to reduce the risk of the vessels to be beset in the most cold arctic conditions and it can also be used as a steering device.
During the years the system has been installed both into newbuild and old ship. Some systems have been even for seasonal use with capability to be removed for summer season.
New techologies in ship operation, for instance, azimuthing thrusters and operation in double acting mode have reduces the use of the system for normal icebreaking vessels.
However, with the rising interest of offshore industry to the Arctic there will be built a number of stationary drilling units, floating storage/production facilities, which need special attention what comes to keeping the friction between the hull surface and ice on low level, and prevent ice from freezing on the hull as well as helping out doing so called "self ice management".
The paper is a summary of experience gained so far, benefits of the system and how the future oil & gas industry could benefit and some ideas for new ways of using the system.
The air bubbling system was originally developed in the late 1960ies. The main idea is to produce an air flow between the vessel hull and ice to decrease the friction. The system would replace the need to have bow propellers.