4th International Conference on Ships and Marine Systems in Cold Regions, March 1990, Calgary
The effect of ice-model surface friction on ship model resistance was investigated with a series of model tests conducted in the ice tank at the Institute for Marine Dynamics (IMD). The 1:30 scale ship models were based on the Arctic Class OBO ARCTIC, operated by Canarctic Shipping Company Limited. Three different friction coefficients between the model surface and the model ice were selected, covering two orders of magnitude. The bow, parallel midbody, and stern portions of the model surfaces were finished to yield the selected friction coefficients and then tested in various combinations. A further variation was achieved by combining the bow and stern with a very short parallel midbody, resulting in an overall ship length reduction of 35%. The models were tested in 30 mm and 50 mm thick level EGAD ice sheets, with target flexural strength 19 kPa. Tests were also conducted in presawn ice. The test data is presented in the paper and the trends, which are consistent throughout, are discussed. An increase in friction at the bow resulted in increases in total resistance of up to 50% over the range of speeds tested, The effect of friction along the parallel midbody was less significant. The ice friction contribution to resistance increased with increasing speed, and the speed dependence was stronger when larger areas of the ship model surface were compared. The ice friction resistance can be distinguished from the resistance due to other causes.